GMAT® OFFICIAL GUIDE 2018 GMAT
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- GMAT® OFFICIAL GUIDE 2018
- Table of Contents
- Letter from the President and CEO, GMAC®
- 1.0 What Is the GMAT® Exam?
- 1.0 What Is the GMAT® Exam?
- 1.1 Why Take the GMAT® Exam?
- 1.2 GMAT® Exam Format
- 1.3 What Is the Content of the Test Like?
- 1.4 Integrated Reasoning Section
- 1.5 Quantitative Section
- 1.6 Verbal Section
- 1.7 Analytical Writing Assessment
- 1.8 What Computer Skills Will I Need?
- 1.9 What Are the Test Centers Like?
- 1.10 How Are Scores Calculated?
- 1.11 Test Development Process
- 2.0 How to Prepare
- 3.0 Diagnostic Test
- 4.0 Math Review
- 5.0 Problem Solving
- 6.0 Data Sufficiency
- 7.0 Reading Comprehension
- 8.0 Critical Reasoning
- 9.0 Sentence Correction
- 10.0 Integrated Reasoning
- 11.0 Analytical Writing Assessment
- Appendix A Answer Sheets
- Advert
- EULA
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Online Question Bank Information
Your purchase of GMAT® Official Guide 2018 offers the original purchaser access to the online question
bank and 58 Integrated Reasoning practice questions, and the diagnostic test for a period of 12 months
from the date of activation.
To obtain an access code, go to www.wiley.com/go/officialgmatbook to verify your purchase. Once you
verify your purchase, you will be emailed an access code and instructions for setting up a personal login.
Note: GMAC and Wiley are not responsible for providing access to the online companion for customers
who purchase or borrow used copies of this book. is code will only provide you with access to the
question bank. It will not work for other Wiley or GMAC password-protected websites.
For customer support, please visit http://wileyactual.com/gmat/help
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mba.com
Of cial Guide
Book + Online
The de nitive guide from the makers of the GMAT® exam
2018
The ONLY
source of real
GMAT® questions
from past
exams
This edition includes
130 never-before-seen questions
Graduate Management Admission Council®
GMAT® OFFICIAL GUIDE 2018
Copyright © 2017 by the Graduate Management Admission Council®. All rights reserved.
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Printed in the United States of America
10 9 8 7 6 5 4 3 2 1
Table of Contents Letter from the President and CEO, GMAC® v
1.0 What Is the GMAT® Exam? 2
1.0 What Is the GMAT® Exam? 3
1.1 Why Take the GMAT® Exam? 3
1.2 GMAT® Exam Format 4
1.3 What Is the Content of the Test Like? 5
1.4 Integrated Reasoning Section 6
1.5 Quantitative Section 6
1.6 Verbal Section 6
1.7 Analytical Writing Assessment 7
1.8 What Computer Skills Will I Need? 7
1.9 What Are the Test Centers Like? 7
1.10 How Are Scores Calculated? 7
1.11 Test Development Process 8
2.0 How to Prepare 10
2.0 How to Prepare 11
2.1 How Should I Prepare to Take the Test? 11
2.2 What About Practice Tests? 11
2.3 How Should I Use the Diagnostic Test? 12
2.4 Where Can I Get Additional Practice? 12
2.5 General Test-Taking Suggestions 12
3.0 Diagnostic Test 14
3.0 Diagnostic Test 15
3.1 Quantitative Questions 16
3.2 Verbal Questions 23
3.3 Quantitative and Verbal Answer Keys 40
3.4 Interpretive Guide 40
3.5 Quantitative Answer Explanations 41
3.6 Verbal Answer Explanations 60
4.0 Math Review 100
4.0 Math Review 101
4.1 Arithmetic 102
4.2 Algebra 114
4.3 Geometry 122
4.4 Word Problems 134
5.0 Problem Solving 142
5.0 Problem Solving 143
5.1 Test-Taking Strategies 144
5.2 The Directions 144
5.3 Practice Questions 146
5.4 Answer Key 181
5.5 Answer Explanations 183
6.0 Data Suf ciency 264
6.0 Data Suf ciency 265
6.1 Test-Taking Strategies 266
6.2 The Directions 268
6.3 Practice Questions 270
6.4 Answer Key 288
6.5 Answer Explanations 289
7.0 Reading Comprehension 356
7.0 Reading Comprehension 357
7.1 What Is Measured 358
7.2 Test-Taking Strategies 360
7.3 The Directions 361
7.4 Practice Questions 362
7.5 Answer Key 423
7.6 Answer Explanations 424
8.0 Critical Reasoning 504
8.0 Critical Reasoning 505
8.1 What Is Measured 506
8.2 Test-Taking Strategies 506
8.3 The Directions 507
8.4 Practice Questions 508
8.5 Answer Key 546
8.6 Answer Explanations 547
9.0 Sentence Correction 672
9.0 Sentence Correction 673
9.1 Basic English Grammar Rules 673
9.2 Study Suggestions 678
9.3 What Is Measured 678
9.4 Test-Taking Strategies 678
9.5 The Directions 679
9.6 Practice Questions 680
9.7 Answer Key 709
9.8 Answer Explanations 710
10.0 Integrated Reasoning 788
10.0 Integrated Reasoning 789
10.1 What Is Measured 789
10.2 The Question Types 790
10.3 Test-Taking Strategies 797
10.4 The Directions 799
11.0 Analytical Writing Assessment 800
11.0 Analytical Writing Assessment 801
11.1 What Is Measured 801
11.2 Test-Taking Strategies 802
11.3 The Directions 802
11.4 GMAT® Scoring Guide: Analysis of an Argument 803
11.5 Sample: Analysis of an Argument 805
11.6 Analysis of an Argument Sample Topics 809
Appendix A Answer Sheets 841
Diagnostic Answer Sheet—Quantitative 841
Diagnostic Answer Sheet—Verbal 841
Problem Solving Answer Sheet 842
Data Suf ciency Answer Sheet 843
Reading Comprehension Answer Sheet 844
Critical Reasoning Answer Sheet 845
Sentence Correction Answer Sheet 846
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Dear GMAT Test-Taker,
ank you for your interest in graduate management education. Taking the GMAT® exam lets schools
know that you’re serious about your graduate business education. By using the O cial Guide to prepare
for the GMAT, you’re taking a very important step toward achieving your goals and pursuing admission
to a high-quality business school or master’s program.
is book, GMAT
®
O cial Guide 2018, is designed to help you prepare for and build con dence to do
your best on the GMAT exam. It’s the only guide of its kind on the market that includes real GMAT
exam questions published by the Graduate Management Admission Council (GMAC), the makers of
the exam.
GMAC was founded by the world’s leading business schools in 1953. e GMAT exam was developed
to help people who aspire to careers in management demonstrate their command of the skills needed
for success in the classroom. Schools use and trust the GMAT exam as part of their admissions process
because it’s an excellent predictor of classroom success and your ability to excel in your chosen program.
Today more than 6,500 graduate programs around the world use the GMAT exam to establish their
MBA, graduate-level management degrees and specialized programs as hallmarks of excellence. Nine out
of 10 new MBA enrollments at Top 50 US full-time MBA programs are made using a GMAT
score.
ese facts make us proud and drive us to keep improving the GMAT as well as play a role in helping
you nd and gain admission to the best school or program for you. We’re committed to ensuring
that no talent goes undiscovered, and that more people around the world can pursue opportunities in
graduate management education.
I applaud your commitment to educational success, and I know that this book and the other O cial
GMAT preparation materials available at mba.com will give you the con dence to achieve your
personal best on the GMAT exam and launch or reinvigorate a rewarding career.
I wish you the best success on all your educational and professional endeavors in the future.
Sincerely,
Sangeet Chow a
CEO of the Graduate Management Admission Council
GMAT® Offi cial Guide 2018
2
1.0 What Is the GMAT
® Exam?
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3
1.0 What Is the GMAT® Exam?
1.0 What Is the GMAT
® Exam?
e Graduate Management Admission Test
® (GMAT
® ) exam is a standardized exam used in
admissions decisions by more than 6,500 graduate management programs worldwide. It helps you gauge,
and demonstrate to schools, your academic potential for success in graduate-level management studies.
e four‐part exam measures your Analytical Writing, Verbal, Quantitative, and Integrated Reasoning
skills—higher‐order reasoning skills that management faculty worldwide have identi ed as important
for incoming students to have. “Higher-order” reasoning skills involve complex judgments, and include
critical thinking, analysis, and problem solving. Unlike undergraduate grades and curricula, which vary
in their meaning across regions and institutions, your GMAT scores provide a standardized, statistically
valid and reliable measure of how you are likely to perform academically in the core curriculum of a
graduate management program. e GMAT exam’s validity, fairness, and value in admissions have been
well‐established through numerous academic studies.
e GMAT exam is delivered entirely in English and solely on a computer. It is not a test of business
knowledge, subject matter mastery, English vocabulary, or advanced computational skills. e GMAT
exam also does not measure other factors related to success in graduate management study, such as job
experience, leadership ability, motivation, and interpersonal skills. Your GMAT score is intended to be
used as one admissions criterion among other, more subjective, criteria, such as admissions essays and
interviews.
1.1 Why Take the GMAT
® Exam?
Launched in 1954 by a group of nine business schools to
provide a uniform measure of the academic skills needed to
succeed in their programs, the GMAT exam is now used
by more than 6,500 graduate management programs at
approximately 2,100 institutions worldwide.
Taking the GMAT exam helps you stand out in the
admissions process and demonstrate your readiness and
commitment to pursuing graduate management education.
Schools use GMAT scores to help them select the most
quali ed applicants—because they know that candidates
who take the GMAT exam are serious about earning a
graduate business degree, and it’s a proven predictor of a
student’s ability to succeed in his or her chosen program.
When you consider which programs to apply to, you can
look at a school’s use of the GMAT exam as one indicator
of quality. Schools that use the GMAT exam typically list
score ranges or average scores in their class pro les, so you
may also nd these pro les helpful in gauging the academic
competitiveness of a program you are considering and how
well your performance on the exam compares with that of
the students enrolled in the program.
No matter how you perform on the GMAT exam, you should contact the schools that interest you
to learn more and to ask how they use GMAT scores and other criteria (such as your undergraduate
grades, essays, and letters of recommendation) in their admissions processes. School admissions
Myth -vs- FACT
M – If I don’t achieve a high score
on the GMAT, I won’t get into
my top choice schools.
F – There are great schools
available for candidates at any
GMAT score range.
Fewer than 50 of the more than 250,000
people taking the GMAT exam each year get
a perfect score of 800; and many more get
into top business school programs around
the world each year. Admissions Offi cers
use GMAT scores as one component in their
admissions decisions, in conjunction with
undergraduate records, application essays,
interviews, letters of recommendation, and
other information when deciding whom
to accept into their programs. Visit School
Finder on mba.com to learn about schools
that are the best fi t for you.
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GMAT® Offi cial Guide 2018
4
o ces, web sites, and materials published by schools are the key sources of information when you are
doing research about where you might want to go to business school.
For more information on the GMAT, test preparation materials, registration, how to use and send your
GMAT scores to schools, and applying to business school, please visit mba.com.
1.2 GMAT
® Exam Format
e GMAT exam consists of four separately timed sections
(see the table on the next page). For the Analytical Writing
Assessment (AWA) essay prompt, you will have 30 minutes
to type your essay on a computer keyboard. e 30-minute
Integrated Reasoning section features 12 question prompts
in four di erent formats. ere are two 75-minute,
multiple-choice sections: the Quantitative section, with 37
questions, and the Verbal section, with 41 questions.
e Verbal and Quantitative sections of the GMAT exam
are computer adaptive, which means that the test draws
from a large bank of questions to tailor itself to your ability
level, and you won’t get many questions that are too hard
or too easy for you. e rst question will be of medium
di culty. As you answer each question, the computer scores
your answer and uses it—as well as your responses to all
preceding questions—to select the next question.
Computer‐adaptive tests become more di cult the more
questions you answer correctly, but if you get a question
that seems easier than the last one, it does not necessarily
mean you answered the last question incorrectly. e test
has to cover a range of content, both in the type of question
asked and the subject matter presented.
Because the computer uses your answers to select your next questions, you may not skip questions or go
back and change your answer to a previous question. If you don’t know the answer to a question, try to
eliminate as many choices as possible, then select the answer you think is best.
ough the individual questions are di erent, the mix of question types is the same for every GMAT
exam. Your score is determined by the di culty and statistical characteristics of the questions you
answer as well as the number of questions you answer correctly. By adapting to each test‐taker, the
GMAT exam is able to accurately and e ciently gauge skill levels over a full range of abilities, from
very high to very low.
e test includes the types of questions found in this book and in the online Integrated Reasoning
component, but the format and presentation of the questions are di erent on the computer. When you
take the test:
• Only one question or question prompt at a time is presented on the computer screen.
• e answer choices for the multiple‐choice questions will be preceded by circles, rather than by
letters.
Myth -vs- FACT
M – Getting an easier question
means I answered the last
one wrong.
F – You should not become
distracted by the diffi culty level
of a question.
Most people are not skilled at estimating
question diffi culty, so don’t worry when
taking the test or waste valuable time trying
to determine the diffi culty of the question you
are answering.
To ensure that everyone receives the same
content, the test selects a specifi c number
of questions of each type. The test may call
for your next problem to be a relatively hard
data suffi ciency question involving arithmetic
operations. But, if there are no more
relatively diffi cult data suffi ciency questions
involving arithmetic, you might be given an
easier question.
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5
1.3 What Is the GMAT® Exam? What Is the Content of the Test Like?
• Di erent question types appear in random order in the multiple‐choice and Integrated Reasoning
sections.
• You must select your answer using the computer.
• You must choose an answer and confirm your choice before moving on to the next question.
• You may not go back to previous screens to change answers to previous questions.
1.3 What Is the Content of the Test Like?
e GMAT exam measures higher‐order analytical skills encompassing several types of reasoning. e
Analytical Writing Assessment asks you to analyze the reasoning behind an argument and respond
in writing; the Integrated Reasoning section asks you to interpret and synthesize information from
multiple sources and in di erent formats to make reasoned conclusions; the Quantitative section asks
you to reason quantitatively using basic arithmetic, algebra, and geometry; and the Verbal section asks
you to read and comprehend written material and to reason and evaluate arguments.
Test questions may address a variety of subjects, but all of the information you need to answer the
questions will be included on the exam, with no outside knowledge of the subject matter necessary. e
GMAT exam is not a test of business knowledge, English vocabulary, or advanced computational skills.
You will need to read and write in English and have basic math and English skills to perform well on
the test, but its di culty comes from the English analytical and critical thinking abilities.
e questions in this book are organized by question type and from easiest to most di cult, but keep in mind
that when you take the test, you may see di erent types of questions in any order within each section.
Format of the GMAT
® Exam
Questions Timing
Analytical Writing
Analysis of an Argument
1 30 min.
Integrated Reasoning
Multi‐Source Reasoning
Table Analysis
Graphics Interpretation
Two‐Part Analysis
12 30 min.
Optional break up to 8 min.
Quantitative
Problem Solving
Data Sufficiency
37 75 min.
Optional break up to 8 min.
Verbal
Reading Comprehension
Critical Reasoning
Sentence Correction
41 75 min.
Total Time: 210 min.
GMAT® Offi cial Guide 2018
6
1.4 Integrated Reasoning Section
e Integrated Reasoning section highlights the relevant skills that business managers in today’s data-
driven world need in order to analyze sophisticated streams of data and solve complex problems. It
measures your ability to understand and evaluate multiple sources and types of information—graphic,
numeric, and verbal—as they relate to one another; use both quantitative and verbal reasoning to solve
complex problems; and solve multiple problems in relation to one another.
Four types of questions are used in the Integrated Reasoning section:
• Multi‐Source Reasoning
• Table Analysis
• Graphics Interpretation
• Two‐Part Analysis
Integrated Reasoning questions may be quantitative, verbal, or a combination of both. You will have to
interpret graphics and sort tables to extract meaning from data, but advanced statistical knowledge and
spreadsheet manipulation skills are not necessary. You will have access to an on-screen calculator with
basic functions for the Integrated Reasoning section, but note that the calculator is not available on the
Quantitative section.
To review the Integrated Reasoning question types and test‐taking tips, see chapter 10. For practice
questions of each format, with full answer explanations, visit the Integrated Reasoning online
component using your unique access code found in the inside front cover of the book.
1.5 Quantitative Section
e GMAT Quantitative section measures your ability to reason quantitatively, solve quantitative
problems, and interpret graphic data.
Two types of multiple‐choice questions are used in the Quantitative section:
• Problem Solving
• Data Su ciency
Both are intermingled throughout the Quantitative section, and require basic knowledge of arithmetic,
elementary algebra, and commonly known concepts of geometry.
To review the basic mathematical concepts that you will need to answer Quantitative questions, see the
math review in chapter 4. For test‐taking tips specific to the question types in the Quantitative section,
practice questions, and answer explanations, see chapters 5 and 6.
1.6 Verbal Section
e GMAT Verbal section measures your ability to read and comprehend written material and to
reason and evaluate arguments. e Verbal section includes reading sections from several di erent
content areas. Although you may be generally familiar with some of the material, neither the reading
passages nor the questions assume detailed knowledge of the topics discussed.
7
ree types of multiple‐choice questions are intermingled throughout the Verbal section:
• Reading Comprehension
• Critical Reasoning
• Sentence Correction
All three require basic knowledge of the English language, but the Verbal section is not a test of
advanced vocabulary.
For test‐taking tips specific to each question type in the Verbal section, practice questions, and answer
explanations, see chapters 7 through 9.
1.7 Analytical Writing Assessment
e Analytical Writing Assessment (AWA) consists of one 30‐minute writing task: Analysis of an
Argument. e AWA measures your ability to think critically, communicate your ideas, and formulate
an appropriate and constructive critique. You will type your essay on a computer keyboard.
For test‐taking tips, sample essay responses, answer explanations, and sample Analysis of an Argument
topics, see chapter 11.
1.8 What Computer Skills Will I Need?
e GMAT exam requires only computer skills. You will type your AWA essay on the computer
keyboard using standard word‐processing keystrokes. In the Integrated Reasoning and
multiple‐choice sections, you will select your responses using either your computer mouse or the
keyboard. e Integrated Reasoning section includes basic computer navigation and functions, such as
clicking on tabs and using drop‐down menus to sort tables and select answers.
1.9 What Are the Test Centers Like?
e GMAT exam is administered under standardized conditions at test centers worldwide. Each test
center has a proctored testing room with individual computer workstations that allow you to sit for the
exam under quiet conditions and with some privacy. You will be able to take two optional 8-minute
breaks during the course of the exam. You may not take notes or scratch paper with you into the testing
room, but an erasable notepad and marker will be provided for you to use during the test.
1.10 How Are Scores Calculated?
Verbal and Quantitative sections are scored on a scale of 0 to 60, with scores below 6 or above 51
extremely rare. e Total GMAT score ranges from 200 to 800 and is based on your performance in
these two sections. Your score is determined by:
• e number of questions you answer
• e number of questions you answer correctly or incorrectly
• e level of di culty and other statistical characteristics of each question
1.7 What Is the GMAT® Exam? Analytical Writing Assessment
GMAT® Offi cial Guide 2018
8
Your Verbal, Quantitative, and Total GMAT scores are determined by a complex mathematical
procedure that takes into account the di culty of the questions that were presented to you and how
you answered them. When you answer the easier questions correctly, you get a chance to answer harder
questions, making it possible to earn a higher score. After you have completed all the questions on the
test, or when your time is expired, the computer will calculate your scores. Your scores on the Verbal and
Quantitative sections are combined to produce your Total score which ranges from 200 to 800 in
10 point increments.
e Analytical Writing Assessment consists of one writing task, Analysis of an Argument, and your essay
will be scored two times independently. Essays are evaluated by college and university faculty members
from a variety of disciplines, including management education, who rate the overall quality of your critical
thinking and writing. (For details on how readers are qualified, visit mba.com.) In addition, your response
may be scored by an automated scoring program designed to reflect the judgment of expert readers.
Your essay is scored on a scale of 0 to 6, in half point increments, with 6 being the highest score and
0 the lowest. A score of zero is given for responses that are o topic, are in a foreign language, merely
attempt to copy the topic, consist only of keystroke characters, or are blank. Your AWA score is typically
the average oftwo independent ratings. If the independent scores vary by more than a point, a third
reader adjudicates, but because of ongoing training and monitoring, discrepancies are rare.
Your Integrated Reasoning section is scored on a scale of 1 to 8, in one-point increments. You must
answer all parts of a single question correctly in order to receive credit. No partial credit is given. Like
your AWA score, your Integrated Reasoning score will not count toward your Total score.
Your Analytical Writing Assessment and Integrated Reasoning scores are computed and reported separately
from the other sections of the test and have no e ect on your Verbal, Quantitative, or Total scores. e
schools that you have designated to receive your scores may receive a copy of your Analytical Writing
Assessment essay with your score report. Your own copy of your score report will not include your essay.
Your GMAT score includes a percentile ranking that compares your skill level with other test-takers
from the past three years. e percentile rank of your score shows the percentage of tests taken with
scores lower than your score. Every July, percentile ranking tables are updated. Visit mba.com to view
the most recent percentile rankings tables.
1.11 Test Development Process
e GMAT exam is developed by experts who use standardized procedures to ensure high‐quality,
widely-appropriate test material. All questions are subjected to independent reviews and are revised
or discarded as necessary. Multiple‐choice questions are tested during GMAT exam administrations.
Analytical Writing Assessment tasks are tested on mba.com registrants and then assessed for their
fairness and reliability. For more information on test development, visit mba.com.
10
2.0 How to Prepare
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11
2.0 How to Prepare
Myth -vs- FACT
M – You need very advanced math
skills to get a high GMAT score.
F – The GMAT measures your
reasoning and critical thinking
abilities, rather than your
advanced math skills.
The GMAT exam only requires basic quantitative
skills. You should review the math skills
(algebra, geometry, basic arithmetic) presented
in this guide (chapter 4) and the GMAT
®
Offi cial Guide Quantitative Review 2018. The
diffi culty of GMAT Quantitative questions stems
from the logic and analysis used to solvethe
problems and not the underlying math skills.
2.0 How to Prepare
2.1 How Should I Prepare to Take the Test?
e GMAT® exam is designed speci cally to measure reasoning skills needed for management
education, and the test contains several question formats unique to the GMAT exam. At a minimum,
you should be familiar with the test format and the question formats before you sit for the test. Because
the GMAT exam is a timed exam, you should practice answering test questions, not only to better
understand the question formats and the skills they require, but also to help you learn to pace yourself
so you can nish each section when you sit for the exam.
Because the exam measures reasoning rather than
subject matter knowledge, you most likely will not nd
it helpful to memorize facts. You do not need to study
advanced mathematical concepts, but you should be sure
your grasp of basic arithmetic, algebra, and geometry is
sound enough that you can use these skills in quantitative
problem solving. Likewise, you do not need to study
advanced vocabulary words, but you should have a rm
understanding of basic English vocabulary and grammar
for reading, writing, and reasoning.
is book and other study materials released by the
Graduate Management Admission Council (GMAC)
are the ONLY source of questions that have been retired
from the GMAT exam. All questions that appear or
have appeared on the GMAT exam are copyrighted and
owned by GMAC, which does not license them to be
reprinted elsewhere. Accessing live Integrated Reasoning,
Quantitative, or Verbal test questions in advance or sharing test content during or after you take the test
is a serious violation, which could cause your scores to be canceled and schools to be noti ed. In cases of
a serious violation, you may be banned from future testing and other legal remedies may be pursued.
2.2 What About Practice Tests?
e Quantitative and Verbal sections of the GMAT exam are computer adaptive, and the Integrated
Reasoning section includes questions that require you to use the computer to sort tables and navigate to
di erent sources of information. Our o cial practice materials will help you get comfortable with the
format of the test and better prepare for exam day. Two full-length GMAT practice exams are available at no
charge for those who have created an account on mba.com. e practice exams include computer‐adaptive
Quantitative and Verbal sections, plus additional practice questions, information about the test, and tutorials
to help you become familiar with how the GMAT exam will appear on the computer screen at the test center.
To maximize your studying e orts with the free practice exams, you should leverage o cial practice
materials as you start to prepare for the test. Take one practice test to make yourself familiar with the
exam and to get a baseline score. After you have studied using this book and other study materials, take
the second practice test to determine whether you need to shift your focus to other areas you need to
strengthen. Note that the free practice tests may include questions that are also published in this book.
As your test day approaches, consider taking more o cial practice tests to help measure your progress
and give you a better idea of how you might score on exam day.
GMAT® Offi cial Guide 2018
12
2.3 How Should I Use the Diagnostic Test?
is book contains a Diagnostic Test to help you determine the types of Quantitative and Verbal
questions that you need to practice most. You should take the Diagnostic Test around the same time
that you take the rst GMAT practice test. e Diagnostic Test will give you a rating— below average,
average, above average, or excellent —of your skills in each type of GMAT test question. ese ratings will
help you identify areas to focus on as you prepare for the GMAT exam.
e Diagnostic Test does not include Integrated Reasoning or Analytical Writing Assessment questions.
Use the results of the Diagnostic Test to help you select the right chapter of this book to start with.
Next, read the introductory material carefully, and answer the practice questions in that chapter.
Remember, the questions in the chapters are organized by di culty, from easiest to most di cult. Make
sure you follow the directions for each type of question and try to work as quickly and as e ciently as
possible. en review the explanations for the correct answers, spending as much time as necessary to
familiarize yourself with the range of questions or problems presented.
2.4 Where Can I Get Additional Practice?
If you would like additional practice, GMAT
®
O cial Guide 2018 Quantitative Review and GMAT
®
O cial Guide 2018 Verbal Review each o er 300 additional questions that are not published in this
guide. You can also nd more Quantitative, Verbal, and Integrated Reasoning practice questions, full-
length, computer-adaptive practice exams, Analytical Writing Assessment practice prompts, and other
helpful study materials at mba.com.
2.5 General Test-Taking Suggestions
Specific test‐taking strategies for individual question types are presented later in this book. e
following are general suggestions to help you perform your best on the test.
1. Use your time wisely.
Although the GMAT exam stresses accuracy more than speed, it is important to use your time wisely. On
average, you will have about 1¾ minutes for each Verbal question, about 2 minutes for each Quantitative
question, and about 2½ minutes for each Integrated Reasoning question, some of which have multiple
questions. Once you start the test, an onscreen clock will show the time you have left. You can hide this
display if you want, but it is a good idea to check the clock periodically to monitor your progress. e clock
will automatically alert you when 5 minutes remain for the section you are working on.
2. Answer practice questions ahead of time.
After you become generally familiar with all question types, use the practice questions in this book
and the online Integrated Reasoning component to prepare for the actual test. It may beuseful to time
yourself as you answer the practice questions to get an idea of how long you will have for each question
when you sit for the actual test, as well as to determine whether you areanswering quickly enough to
nish the test inthe allotted time.
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13
2.0 How to Prepare General Test-Taking Suggestions
3. Read all test directions carefully.
e directions explain exactly what is required to
answer each question type. If you read hastily, you may
miss important instructions and impact your ability to
answer correctly. To review directions during the test,
click on the Help icon. But be aware that the time you
spend reviewing directions will count against your time
allotment for that section of the test.
4. Read each question carefully and thoroughly.
Before you answer a question, determine exactly what is
being asked and then select the best choice. Never skim
a question or the possible answers; skimming may cause
you to miss important information or nuances.
5. Do not spend too much time on any one question.
If you do not know the correct answer, or if the
question is too time consuming, try to eliminate choices
you know are wrong, select the best of the remaining
answer choices, and move on to the next question.
Not completing sections and randomly guessing
answers to questions at the end of each test section
can signi cantly lower your score. As long as you have
worked on each section, you will receive a score even if
you do not nish one or more sections in the allotted
time. You will not earn points for questions you never
get to see.
6. Confirm your answers ONLY when you are ready to
move on.
On the Quantitative and Verbal sections, once you have
selected your answer to a multiple‐choice question,
you will be asked to confirm it. Once you confirm your
response, you cannot go back and change it. You may
not skip questions. In the Integrated Reasoning section,
there may be several questions based on information
provided in the same question prompt. When there
is more than one response on a single screen, you can
change your response to any of the questions on the
screen before moving on to the next screen. However,
you may not navigate back to a previous screen to
change any responses.
7. Plan your essay answer before you begin to write.
e best way to approach the Analysis of an Argument
section is to read the directions carefully, take a few minutes to think about the question, and plan a
response before you begin writing. Take time to organize your ideas and develop them fully, but leave
time to reread your response and make any revisions that you think would improve it.
Myth -vs- FACT
M – It is more important to respond
correctly to the test questions
than it is to fi nish the test.
F – There is a signifi cant penalty
for not completing the GMAT
exam.
Pacing is important. If you are stumped by a
question, give it your best guess and move
on. If you guess incorrectly, the computer
program will likely give you an easier
question, which you are likely to answer
correctly, and the computer will rapidly
return to giving you questions matched to
your ability. If you don’t fi nish the test, your
score will be reduced. Failing to answer fi ve
verbal questions, for example, could reduce
your score from the 91st percentile to the
77th percentile.
Myth -vs- FACT
M – The fi rst 10 questions are
critical and you should invest
the most time on those.
F – All questions count.
The computer-adaptive testing algorithm
uses each answered question to obtain an
initial estimate. However, as you continue to
answer questions, the algorithm self-corrects
by computing an updated estimate on the
basis of all the questions you have answered,
and then administers items that are closely
matched to this new estimate of your ability.
Your fi nal score is based on all your responses
and considers the diffi culty of all the
questions you answered. Taking additional
time on the fi rst 10 questions will not game
the system and can hurt your ability to fi nish
the test.
14
3.0 Diagnostic Test
15
3.0 Diagnostic Test
3.0 Diagnostic Test
Like the practice sections later in the book, the Diagnostic Test uses questions from real GMAT®
exams. e purpose of the Diagnostic Test is to help you determine how skilled you are in answering
each of the five types of questions on the GMAT exam: problem solving, data sufficiency, reading
comprehension, critical reasoning, and sentence correction.
Scores on the Diagnostic Test are designed to help you answer the question, “If all the questions on the
GMAT exam were like the questions in this section, how well would I do?” Your scores are classified as
being excellent, above average, average, or below average, relative to the scores of other test‐takers. You
can use this information to focus your test‐preparation activities.
Instructions
1. Take your time answering these questions. e Diagnostic Test is not timed.
2. If you are stumped by a question, you should guess and move on, just like you should do on the
real GMAT exam.
3. You can take one segment at a time, if you want. It is better to finish an entire section
(Quantitative or Verbal) in one sitting, but this is not a requirement.
4. You can go back and change your answers in the Diagnostic Test.
5. After you take the test, check your answers using the answer key that follows the test. e number
of correct answers is your raw score.
6. Convert your raw score, using the table provided.
Note: e Diagnostic Test is designed to give you guidance on how to prepare for the GMAT exam;
however, a strong score on one type of question does not guarantee that you will perform as well on the
real GMAT exam. e statistical reliability of scores on the Diagnostic Test ranges from 0.75 to 0.89,
and the subscale classification is about 85%–90% accurate, meaning that your scores on the Diagnostic
Test are a good, but not perfect, measure of how you are likely to perform on the real test. Use the tests
on the free online software to obtain a good estimate of your expected GMAT Verbal, Quantitative, and
Total scores.
You should not compare the number of questions you got right in each section. Instead, you should
compare how your responses are rated in each section.
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GMAT® Official Guide 2018
16
1. Last month a certain music club offered a discount
to preferred customers. After the first compact disc
purchased, preferred customers paid $3.99 for each
additional compact disc purchased. If a preferred
customer purchased a total of 6 compact discs and
paid $15.95 for the first compact disc, then the dollar
amount that the customer paid for the 6 compact
discs is equivalent to which of the following?
(A) 5(4.00) + 15.90
(B) 5(4.00) + 15.95
(C) 5(4.00) + 16.00
(D) 5(4.00 − 0.01) + 15.90
(E) 5(4.00 − 0.05) + 15.95
2. The average (arithmetic mean) of the integers from
200 to 400, inclusive, is how much greater than the
average of the integers from 50 to 100, inclusive?
(A) 150
(B) 175
(C) 200
(D) 225
(E) 300
3. The sequence
aaaa,,,,,
n123
is such that
aaa
2
n
nn
12
=
+
−− for all
n3.≥
If
a4
3
=
and
a20
5
=
what is the value of
a6
?
(A) 12
(B) 16
(C) 20
(D) 24
(E) 28
4. Among a group of 2,500 people, 35 percent invest
in municipal bonds, 18 percent invest in oil stocks,
and 7percent invest in both municipal bonds and oil
stocks. If 1 person is to be randomly selected from the
2,500 people, what is the probability that the person
selected will be one who invests in municipal bonds but
NOT in oil stocks?
(A)
9
50
(B)
7
25
(C)
7
20
(D)
21
50
(E)
27
50
5. A closed cylindrical tank contains 36π cubic feet of
water and is filled to half its capacity. When the tank
is placed upright on its circular base on level ground,
the height of the water in the tank is 4 feet. When the
tank is placed on its side on level ground, what is the
height, in feet, of the surface of the water above the
ground?
(A) 2
(B) 3
(C) 4
(D) 6
(E) 9
3.1 Quantitative Questions
Problem Solving
Solve the problem and indicate the best of the answer choices given.
Numbers: All numbers used are real numbers.
Figures: All figures accompanying problem solving questions are intended to provide information
useful in solving the problems. Figures are drawn as accurately as possible. Exceptions will
be clearly noted. Lines shown as straight are straight, and lines that appear jagged are also
straight. The positions of points, angles, regions, etc., exist in the order shown, and angle
measures are greater than zero. All figures lie in a plane unless otherwise indicated.
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17
3.1 Diagnostic Test Quantitative Questions
6. A marketing firm determined that, of 200 households
surveyed, 80 used neither Brand A nor Brand B soap,
60 used only Brand A soap, and for every household
that used both brands of soap, 3 used only Brand B
soap. How many of the 200 households surveyed used
both brands of soap?
(A) 15
(B) 20
(C) 30
(D) 40
(E) 45
7. A certain club has 10 members, including Harry. One
of the 10 members is to be chosen at random to be
the president, one of the remaining 9 members is to
be chosen at random to be the secretary, and one of
the remaining 8 members is to be chosen at random
to be the treasurer. What is the probability that Harry
will be either the member chosen to be the secretary
or the member chosen to be the treasurer?
(A)
1
720
(B)
1
80
(C)
1
10
(D) 1
9
(E)
1
5
8. If a certain toy store’s revenue in November was
2
5
of its revenue in December and its revenue in January
was
1
4
of its revenue in November, then the store’s
revenue in December was how many times the average
(arithmetic mean) of its revenues in November and
January?
(A)
1
4
(B)
1
2
(C)
2
3
(D) 2
(E) 4
9. A researcher computed the mean, the median, and the
standard deviation for a set of performance scores.
If 5 were to be added to each score, which of these
three statistics would change?
(A) The mean only
(B) The median only
(C) The standard deviation only
(D) The mean and the median
(E) The mean and the standard deviation
x°
v°w°
y°
z°
10. In the figure shown, what is the value of
v + x + y + z + w?
(A) 45
(B) 90
(C) 180
(D) 270
(E) 360
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GMAT® Official Guide 2018
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11. Of the three‐digit integers greater than 700, how many
have two digits that are equal to each other and the
remaining digit different from the other two?
(A) 90
(B) 82
(C) 80
(D) 45
(E) 36
12. Positive integer y is 50 percent of 50 percent of
positive integer x, and y percent of x equals 100. What
is the value of x?
(A) 50
(B) 100
(C) 200
(D) 1,000
(E) 2,000
13. If s and t are positive integers such that
s
t
64.12=,
which of the following could be the remainder when s
is divided by t?
(A) 2
(B) 4
(C) 8
(D) 20
(E) 45
14. Of the 84 parents who attended a meeting at a school,
35 volunteered to supervise children during the school
picnic and 11 volunteered both to supervise children
during the picnic and to bring refreshments to the
picnic. If the number of parents who volunteered
to bring refreshments was 1.5 times the number
of parents who neither volunteered to supervise
children during the picnic nor volunteered to bring
refreshments, how many of the parents volunteered to
bring refreshments?
(A) 25
(B) 36
(C) 38
(D) 42
(E) 45
15. The product of all the prime numbers less than 20 is
closest to which of the following powers of 10?
(A) 109
(B) 108
(C) 107
(D) 106
(E) 105
16. If
xx
32
21
−= +, then 4x2 =
(A) 1
(B) 4
(C) 2 − 2x
(D) 4x − 2
(E) 6x – 1
17. If
n
16
81
=, what is the value of
n
?
(A)
1
9
(B)
1
4
(C)
4
9
(D)
2
3
(E) 9
2
18. If n is the product of the integers from 1 to 8,
inclusive, how many different prime factors greater
than 1 does n have?
(A) Four
(B) Five
(C) Six
(D) Seven
(E) Eight
19. If k is an integer and 2 < k < 7, for how many different
values of k is there a triangle with sides of lengths
2, 7, and k?
(A) One
(B) Two
(C) Three
(D) Four
(E) Five
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19
3.1 Diagnostic Test Quantitative Questions
20. A right circular cone is inscribed in a hemisphere so
that the base of the cone coincides with the base of
the hemisphere. What is the ratio of the height of the
cone to the radius of the hemisphere?
(A) 3:1
(B) 1:1
(C)
1
2
:1
(D) 2:1
(E) 2:1
21. John deposited $10,000 to open a new savings
account that earned 4 percent annual interest,
compounded quarterly. If there were no other
transactions in the account, what was the amount of
money in John’s account 6 months after the account
was opened?
(A) $10,100
(B) $10,101
(C) $10,200
(D) $10,201
(E) $10,400
22. A container in the shape of a right circular cylinder is
1
2
full of water. If the volume of water in the container
is 36 cubic inches and the height of the container
is 9 inches, what is the diameter of the base of the
cylinder, in inches?
(A)
16
9
π
(B)
4
π
(C)
12
π
(D) 2
π
(E)
4
2
π
23. If the positive integer x is a multiple of 4 and the
positive integer y is a multiple of 6, then xy must be a
multiple of which of the following?
I. 8
II. 12
III. 18
(A) II only
(B) I and II only
(C) I and III only
(D) II and III only
(E) I, II, and III
24. Aaron will jog from home at x miles per hour and then
walk back home by the same route at y miles per hour.
How many miles from home can Aaron jog so that he
spends a total of t hours jogging and walking?
(A)
xt
y
(B)
xt
xy
+
(C)
xyt
xy
+
(D)
xyt
xy
++
(E)
yt
x
t
y
+
−
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GMAT® Official Guide 2018
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Data Sufficiency
Each data sufficiency problem consists of a question and two statements, labeled (1) and (2), which
contain certain data. Using these data and your knowledge of mathematics and everyday facts (such
as the number of days in July or the meaning of the word counterclockwise), decide whether the data
given are sufficient for answering the question and then indicate one of the following answer choices:
A Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D EACH statement ALONE is sufficient.
E Statements (1) and (2) TOGETHER are NOT sufficient.
Note: In data sufficiency problems that ask for the value of a quantity, the data given in the statements
are sufficient only when it is possible to determine exactly one numerical value for the quantity.
Example:
xº
yºzº
P
QR
In ΔPQR, what is the value of x?
(1) PQ = PR
(2) y = 40
Explanation: According to statement (1) PQ = PR; therefore, ΔPQR is isosceles and y = z. Since
x + y + z = 180, it follows that x + 2y = 180. Since statement (1) does not give a value for y, you cannot
answer the question using statement (1) alone. According to statement (2), y = 40; therefore, x + z = 140.
Since statement (2) does not give a value for z, you cannot answer the question using statement (2)
alone. Using both statements together, since x + 2y = 180 and the value of y is given, you can find the
value of x. Therefore, BOTH statements (1) and (2) TOGETHER are sufficient to answer the question, but
NEITHER statement ALONE is sufficient.
Numbers: All numbers used are real numbers.
Figures:
• Figures conform to the information given in the question, but will not necessarily conform to the
additional information given in statements (1) and (2).
• Lines shown as straight are straight, and lines that appear jagged are also straight.
• The positions of points, angles, regions, etc., exist in the order shown, and angle measures are
greater than zero.
• All figures lie in a plane unless otherwise indicated.
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21
3.1 Diagnostic Test Quantitative Questions
25. If the units digit of integer n is greater than 2, what is
the units digit of n?
(1) The units digit of n is the same as the units digit
of n2.
(2) The units digit of n is the same as the units digit
of n3.
26. What is the value of the integer p?
(1) Each of the integers 2, 3, and 5 is a factor of p.
(2) Each of the integers 2, 5, and 7 is a factor of p.
27. If the length of Wanda’s telephone call was rounded
up to the nearest whole minute by her telephone
company, then Wanda was charged for how many
minutes for her telephone call?
(1) The total charge for Wanda’s telephone call was
$6.50.
(2) Wanda was charged $0.50 more for the first
minute of the telephone call than for each minute
after the first.
28. What is the perimeter of isosceles triangle MNP?
(1) MN = 16
(2) NP = 20
29. In a survey of retailers, what percent had purchased
computers for business purposes?
(1) 85 percent of the retailers surveyed who owned
their own store had purchased computers for
business purposes.
(2) 40 percent of the retailers surveyed owned their
own store.
30. The only gift certificates that a certain store sold
yesterday were worth either $100 each or $10 each. If
the store sold a total of 20 gift certificates yesterday,
how many gift certificates worth $10 each did the
store sell yesterday?
(1) The gift certificates sold by the store yesterday
were worth a total of between $1,650 and
$1,800.
(2) Yesterday the store sold more than 15 gift
certificates worth $100 each.
31. Is the standard deviation of the set of measurements
x1, x2, x3, x4, . . ., x20 less than 3?
(1) The variance for the set of measurements is 4.
(2) For each measurement, the difference between
the mean and that measurement is 2.
32. Is the range of the integers 6, 3, y, 4, 5, and x greater
than 9?
(1) y > 3x
(2) y > x > 3
33. Is
5
25 1?
x2
<
+
(1) 5x < 1
(2) x < 0
34. Of the companies surveyed about the skills they
required in prospective employees, 20 percent
required both computer skills and writing skills. What
percent of the companies surveyed required neither
computer skills nor writing skills?
(1) Of those companies surveyed that required
computer skills, half required writing skills.
(2) 45 percent of the companies surveyed required
writing skills but not computer skills.
35. What is the value of w + q?
(1) 3w = 3 – 3q
(2) 5w + 5q = 5
36. If X and Y are points in a plane and X lies inside the
circle C with center O and radius 2, does Y lie inside
circle C?
(1) The length of line segment XY is 3.
(2) The length of line segment OY is 1.5.
37. Is x > y?
(1) x = y + 2
(2)
x
y
2
1
=−
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GMAT® Official Guide 2018
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38. If Paula drove the distance from her home to her
college at an average speed that was greater than
70 kilometers per hour, did it take her less than
3hours to drive this distance?
(1) The distance that Paula drove from her home to
her college was greater than 200 kilometers.
(2) The distance that Paula drove from her home to
her college was less than 205 kilometers.
39. In the xy‐plane, if line k has negative slope and passes
through the point (−5,r), is the x‐intercept of line
kpositive?
(1) The slope of line k is −5.
(2) r > 0
40. If $5,000 invested for one year at p percent simple
annual interest yields $500, what amount must be
invested at k percent simple annual interest for one
year to yield the same number of dollars?
(1) k = 0.8p
(2) k = 8
41. If
xy
z
+
> 0 , is x < 0?
(1) x < y
(2) z < 0
42. Does the integer k have at least three different positive
prime factors?
(1) k
15
is an integer.
(2)
k
10
is an integer.
43. In City X last April, was the average (arithmetic mean)
daily high temperature greater than the median daily
high temperature?
(1) In City X last April, the sum of the 30 daily high
temperatures was 2,160°.
(2) In City X last April, 60 percent of the daily high
temperatures were less than the average daily
high temperature.
44. If m and n are positive integers, is m
n
()
an integer?
(1) m
()
is an integer.
(2) n
()
is an integer.
45. Of the 66 people in a certain auditorium, at most
6people have their birthdays in any one given month.
Does at least one person in the auditorium have a
birthday in January?
(1) More of the people in the auditorium have their
birthday in February than in March.
(2) Five of the people in the auditorium have their
birthday in March.
46. Last year the average (arithmetic mean) salary of the
10 employees of Company X was $42,800. What is
the average salary of the same 10 employees this
year?
(1) For 8 of the 10 employees, this year’s salary is
15 percent greater than last year’s salary.
(2) For 2 of the 10 employees, this year’s salary is
the same as last year’s salary.
47. In a certain classroom, there are 80 books, of which
24 are fiction and 23 are written in Spanish. How many
of the fiction books are written in Spanish?
(1) Of the fiction books, there are 6 more that are
not written in Spanish than are written in Spanish.
(2) Of the books written in Spanish, there are 5
more nonfiction books than fiction books.
48. If p is the perimeter of rectangle Q, what is the value of
p?
(1) Each diagonal of rectangle Q has length 10.
(2) The area of rectangle Q is 48.
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23
3.2 Diagnostic Test Verbal Questions
Line According to economic signaling theory,
consumers may perceive the frequency with
which an unfamiliar brand is advertised as a cue
that the brand is of high quality. The notion that
(5) highly advertised brands are associated with
high‐quality products does have some empirical
support. Marquardt and McGann found that
heavily advertised products did indeed rank high
on certain measures of product quality. Because
(10) large advertising expenditures represent
a significant investment on the part of a
manufacturer, only companies that expect to
recoup these costs in the long run, through
consumers’ repeat purchases of the product,
(15) can afford to spend such amounts.
However, two studies by Kirmani have found
that although consumers initially perceive expensive
advertising as a signal of high brand quality,
at some level of spending the manufacturer’s
(20) advertising effort may be perceived as unreasonably
high, implying low manufacturer confidence in
product quality. If consumers perceive excessive
advertising effort as a sign of a manufacturer’s
desperation, the result may be less favorable
(25) brand perceptions. In addition, a third study by
Kirmani, of print advertisements, found that the
use of color affected consumer perception of
brand quality. Because consumers recognize that
color advertisements are more expensive than
(30) black and white, the point at which repetition of an
advertisement is perceived as excessive comes
sooner for a color advertisement than for a black‐
and‐white advertisement.
49. Which of the following best describes the purpose of
the sentence in lines 10–15?
(A) To show that economic signaling theory fails to
explain a finding
(B) To introduce a distinction not accounted for by
economic signaling theory
(C) To account for an exception to a generalization
suggested by Marquardt and McGann
(D) To explain why Marquardt and McGann’s research
was conducted
(E) To offer an explanation for an observation
reported by Marquardt and McGann
50. The primary purpose of the passage is to
(A) present findings that contradict one explanation
for the effects of a particular advertising practice
(B) argue that theoretical explanations about the
effects of a particular advertising practice are of
limited value without empirical evidence
(C) discuss how and why particular advertising
practices may affect consumers’ perceptions
(D) contrast the research methods used in two
different studies of a particular advertising
practice
(E) explain why a finding about consumer responses
to a particular advertising practice was
unexpected
3.2 Verbal Questions
Reading Comprehension
Each of the reading comprehension questions is based on the content of a passage. After reading the
passage, answer all questions pertaining to it on the basis of what is stated or implied in the passage.
For each question, select the best answer of the choices given.
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GMAT® Official Guide 2018
24
51. Kirmani’s research, as described in the passage,
suggests which of the following regarding consumers’
expectations about the quality of advertised products?
(A) Those expectations are likely to be highest if a
manufacturer runs both black‐and‐white and color
advertisements for the same product.
(B) Those expectations can be shaped by the
presence of color in an advertisement as well as
by the frequency with which an advertisement
appears.
(C) Those expectations are usually high for
frequently advertised new brands but not for
frequently advertised familiar brands.
(D) Those expectations are likely to be higher for
products whose black‐and‐white advertisements
are often repeated than for those whose color
advertisements are less often repeated.
(E) Those expectations are less definitively shaped
by the manufacturer’s advertisements than by
information that consumers gather from other
sources.
52. Kirmani’s third study, as described in the passage,
suggests which of the following conclusions about a
black‐and‐white advertisement?
(A) It can be repeated more frequently than a
comparable color advertisement could before
consumers begin to suspect low manufacturer
confidence in the quality of the advertised
product.
(B) It will have the greatest impact on consumers’
perceptions of the quality of the advertised
product if it appears during periods when a color
version of the same advertisement is also being
used.
(C) It will attract more attention from readers of the
print publication in which it appears if it is used
only a few times.
(D) It may be perceived by some consumers as
more expensive than a comparable color
advertisement.
(E) It is likely to be perceived by consumers as
a sign of higher manufacturer confidence in
the quality of the advertised product than a
comparable color advertisement would be.
53. The passage suggests that Kirmani would be most
likely to agree with which of the following statements
about consumers’ perceptions of the relationship
between the frequency with which a product is
advertised and the product’s quality?
(A) Consumers’ perceptions about the frequency
with which an advertisement appears are their
primary consideration when evaluating an
advertisement’s claims about product quality.
(B) Because most consumers do not notice the
frequency of advertisement, it has little impact
on most consumers’ expectations regarding
product quality.
(C) Consumers perceive frequency of advertisement
as a signal about product quality only when the
advertisement is for a product that is newly on
the market.
(D) The frequency of advertisement is not always
perceived by consumers to indicate that
manufacturers are highly confident about their
products’ quality.
(E) Consumers who try a new product that has been
frequently advertised are likely to perceive the
advertisement’s frequency as having been an
accurate indicator of the product’s quality.
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3.2 Diagnostic Test Verbal Questions
25
Line The idea of the brain as an information
processor—a machine manipulating blips of energy
according to fathomable rules—has come to
dominate neuroscience. However, one enemy of
(5) the brain‐as‐computer metaphor is John R. Searle,
a philosopher who argues that since computers
simply follow algorithms, they cannot deal with
important aspects of human thought such as
meaning and content. Computers are syntactic,
(10) rather than semantic, creatures. People, on the
other hand, understand meaning because they have
something Searle obscurely calls the causal powers
of the brain.
Yet how would a brain work if not by reducing
(15) what it learns about the world to information—some
kind of code that can be transmitted from neuron
to neuron? What else could meaning and content
be? If the code can be cracked, a computer should
be able to simulate it, at least in principle. But
(20) even if a computer could simulate the workings
of the mind, Searle would claim that the machine
would not really be thinking; it would just be acting
as if it were. His argument proceeds thus: if a
computer were used to simulate a stomach, with
(25) the stomach’s churnings faithfully reproduced on a
video screen, the machine would not be digesting
real food. It would just be blindly manipulating the
symbols that generate the visual display.
Suppose, though, that a stomach were simulated
(30) using plastic tubes, a motor to do the churning, a
supply of digestive juices, and a timing mechanism.
If food went in one end of the device, what came out
the other end would surely be digested food. Brains,
unlike stomachs, are information processors, and if
(35) one information processor were made to simulate
another information processor, it is hard to see
how one and not the other could be said to think.
Simulated thoughts and real thoughts are made of
the same element: information. The representations
(40) of the world that humans carry around in their heads
are already simulations. To accept Searle’s argument,
one would have to deny the most fundamental notion
in psychology and neuroscience: that brains work
by processing information.
54. The main purpose of the passage is to
(A) propose an experiment
(B) analyze a function
(C) refute an argument
(D) explain a contradiction
(E) simulate a process
55. Which of the following is most consistent with Searle’s
reasoning as presented in the passage?
(A) Meaning and content cannot be reduced to
algorithms.
(B) The process of digestion can be simulated
mechanically, but not on a computer.
(C) Simulated thoughts and real thoughts are
essentially similar because they are composed
primarily of information.
(D) A computer can use “causal powers” similar
to those of the human brain when processing
information.
(E) Computer simulations of the world can achieve
the complexity of the brain’s representations of
the world.
56. The author of the passage would be most likely to
agree with which of the following statements about the
simulation of organ functions?
(A) An artificial device that achieves the functions of
the stomach could be considered a valid model
of the stomach.
(B) Computer simulations of the brain are best
used to crack the brain’s codes of meaning and
content.
(C) Computer simulations of the brain challenge
ideas that are fundamental to psychology and
neuroscience.
(D) Because the brain and the stomach both act
as processors, they can best be simulated by
mechanical devices.
(E) The computer’s limitations in simulating digestion
suggest equal limitations in computer‐simulated
thinking.
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57. It can be inferred that the author of the passage
believes that Searle’s argument is flawed by its
failure to
(A) distinguish between syntactic and semantic
operations
(B) explain adequately how people, unlike
computers, are able to understand meaning
(C) provide concrete examples illustrating its claims
about thinking
(D) understand how computers use algorithms to
process information
(E) decipher the code that is transmitted from
neuron to neuron in the brain
58. From the passage, it can be inferred that the author
would agree with Searle on which of the following
points?
(A) Computers operate by following algorithms.
(B) The human brain can never fully understand its
own functions.
(C) The comparison of the brain to a machine is
overly simplistic.
(D) The most accurate models of physical processes
are computer simulations.
(E) Human thought and computer‐simulated thought
involve similar processes of representation.
59. Which of the following most accurately represents
Searle’s criticism of the brain‐as‐computer metaphor,
as that criticism is described in the passage?
(A) The metaphor is not experimentally verifiable.
(B) The metaphor does not take into account the
unique powers of the brain.
(C) The metaphor suggests that a brain’s functions
can be simulated as easily as those of a
stomach.
(D) The metaphor suggests that a computer can
simulate the workings of the mind by using the
codes of neural transmission.
(E) The metaphor is unhelpful because both the
brain and the computer process information.
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3.2 Diagnostic Test Verbal Questions
27
Line Women’s grassroots activism and their vision
of a new civic consciousness lay at the heart of
social reform in the United States throughout the
Progressive Era, the period between the depression
(5) of 1893 and America’s entry into the Second
World War. Though largely disenfranchised except
for school elections, white middle‐class women
reformers won a variety of victories, notably in
the improvement of working conditions, especially
(10) for women and children. Ironically, though,
child labor legislation pitted women of different
classes against one another. To the reformers,
child labor and industrial home work were equally
inhumane practices that should be outlawed, but,
(15) as a number of women historians have recently
observed, working‐class mothers did not always
share this view. Given the precarious finances of
working‐class families and the necessity of pooling
the wages of as many family members as possible,
(20) working‐class families viewed the passage and
enforcement of stringent child labor statutes as a
personal economic disaster and made strenuous
efforts to circumvent child labor laws. Yet
reformers rarely understood this resistance in terms
(25) of the desperate economic situation of working‐
class families, interpreting it instead as evidence
of poor parenting. This is not to dispute women
reformers’ perception of child labor as a terribly
exploitative practice, but their understanding of
(30) child labor and their legislative solutions for ending
it failed to take account of the economic needs of
working‐class families.
60. The primary purpose of the passage is to
(A) explain why women reformers of the Progressive
Era failed to achieve their goals
(B) discuss the origins of child labor laws in the late
nineteenth and early twentieth centuries
(C) compare the living conditions of working‐class
and middle‐class women in the Progressive Era
(D) discuss an oversight on the part of women
reformers of the Progressive Era
(E) revise a traditional view of the role played by
women reformers in enacting Progressive Era
reforms
61. The view mentioned in line 17 of the passage refers to
which of the following?
(A) Some working‐class mothers’ resistance to the
enforcement of child labor laws
(B) Reformers’ belief that child labor and industrial
home work should be abolished
(C) Reformers’ opinions about how working‐class
families raised their children
(D) Certain women historians’ observation that there
was a lack of consensus between women of
different classes on the issue of child labor and
industrial home work
(E) Working‐class families’ fears about the adverse
consequences that child labor laws would have
on their ability to earn an adequate living
62. The author of the passage mentions the observations
of women historians (lines 15–17) most probably in
order to
(A) provide support for an assertion made in the
preceding sentence (lines 10–12)
(B) raise a question that is answered in the last
sentence of the passage (lines 27–32)
(C) introduce an opinion that challenges a statement
made in the first sentence of the passage
(D) offer an alternative view to the one attributed in
the passage to working‐class mothers
(E) point out a contradiction inherent in the
traditional view of child labor reform as it is
presented in the passage
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63. The passage suggests that which of the following was
a reason for the difference of opinion between working‐
class mothers and women reformers on the issue of
child labor?
(A) Reformers’ belief that industrial home work was
preferable to child labor outside the home
(B) Reformers’ belief that child labor laws should
pertain to working conditions but not to pay
(C) Working‐class mothers’ resentment at reformers’
attempts to interfere with their parenting
(D) Working‐class mothers’ belief that child labor was
an inhumane practice
(E) Working‐class families’ need for every
employable member of their families to earn
money
64. The author of the passage asserts which of the
following about women reformers who tried to abolish
child labor?
(A) They alienated working‐class mothers by
attempting to enlist them in agitating for
progressive causes.
(B) They underestimated the prevalence of child
labor among the working classes.
(C) They were correct in their conviction that child
labor was deplorable but shortsighted about the
impact of child labor legislation on working‐class
families.
(D) They were aggressive in their attempts to
enforce child labor legislation, but were
unable to prevent working‐class families from
circumventing them.
(E) They were prevented by their nearly total
disenfranchisement from making significant
progress in child labor reform.
65. According to the passage, one of the most striking
achievements of white middle‐class women reformers
during the Progressive Era was
(A) gaining the right to vote in school elections
(B) mobilizing working‐class women in the fight
against child labor
(C) uniting women of different classes in grassroots
activism
(D) improving the economic conditions of working‐
class families
(E) improving women’s and children’s working
conditions
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3.2 Diagnostic Test Verbal Questions
66. Vasquez‐Morrell Assurance specializes in insuring
manufacturers. Whenever a policyholder makes a
claim, a claims adjuster determines the amount that
Vasquez‐Morrell is obligated to pay. Vasquez‐Morrell
is cutting its staff of claims adjusters by 15 percent.
To ensure that the company’s ability to handle claims
promptly is affected as little as possible by the staff
cuts, consultants recommend that Vasquez‐Morrell lay
off those adjusters who now take longest, on average,
to complete work on claims assigned to them.
Which of the following, if true, most seriously calls into
question the consultants’ criterion for selecting the
staff to be laid off?
(A) If the time that Vasquez‐Morrell takes to settle
claims increases significantly, it could lose
business to other insurers.
(B) Supervisors at Vasquez‐Morrell tend to assign
the most complex claims to the most capable
adjusters.
(C) At Vasquez‐Morrell, no insurance payments are
made until a claims adjuster has reached a final
determination on the claim.
(D) There are no positions at Vasquez‐Morrell
to which staff currently employed as claims
adjusters could be reassigned.
(E) The premiums that Vasquez‐Morrell currently
charges are no higher than those charged for
similar coverage by competitors.
67. Prolonged spells of hot, dry weather at the end of the
grape‐growing season typically reduce a vineyard’s
yield, because the grapes stay relatively small. In
years with such weather, wine producers can make
only a relatively small quantity of wine from a given
area of vineyards. Nonetheless, in regions where
wine producers generally grow their own grapes,
analysts typically expect a long, hot, dry spell late in
the growing season to result in increased revenues for
local wine producers.
Which of the following, if true, does most to justify the
analysts’ expectation?
(A) The lower a vineyard’s yield, the less labor is
required to harvest the grapes.
(B) Long, hot, dry spells at the beginning of the
grape‐growing season are rare, but they can
have a devastating effect on a vineyard’s yield.
(C) Grapes grown for wine production are typically
made into wine at or near the vineyard in which
they were grown.
(D) When hot, dry spells are followed by heavy rains,
the rains frequently destroy grape crops.
(E) Grapes that have matured in hot, dry weather
make significantly better wine than ordinary
grapes.
Critical Reasoning
Each of the critical reasoning questions is based on a short argument, a set of statements, or a plan of
action. For each question, select the best answer of the choices given.
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68. In the past, most children who went sledding in the
winter snow in Verland used wooden sleds with runners
and steering bars. Ten years ago, smooth plastic sleds
became popular; they go faster than wooden sleds but
are harder to steer and slow. The concern that plastic
sleds are more dangerous is clearly borne out by the
fact that the number of children injured while sledding
was much higher last winter than it was 10 years ago.
Which of the following, if true in Verland, most seriously
undermines the force of the evidence cited?
(A) A few children still use traditional wooden sleds.
(B) Very few children wear any kind of protective
gear, such as helmets, while sledding.
(C) Plastic sleds can be used in a much wider variety
of snow conditions than wooden sleds can.
(D) Most sledding injuries occur when a sled collides
with a tree, a rock, or another sled.
(E) Because the traditional wooden sleds can carry
more than one rider, an accident involving a
wooden sled can result in several children being
injured.
69. Metal rings recently excavated from seventh‐century
settlements in the western part of Mexico were made
using the same metallurgical techniques as those
used by Ecuadorian artisans before and during that
period. These techniques are sufficiently complex to
make their independent development in both areas
unlikely. Since the people of these two areas were
in cultural contact, archaeologists hypothesize that
the metallurgical techniques used to make the rings
found in Mexico were learned by Mexican artisans from
Ecuadorian counterparts.
Which of the following would it be most useful to
establish in order to evaluate the archaeologists’
hypothesis?
(A) Whether metal objects were traded from
Ecuador to western Mexico during the seventh
century
(B) Whether travel between western Mexico and
Ecuador in the seventh century would have been
primarily by land or by sea
(C) Whether artisans from western Mexico could
have learned complex metallurgical techniques
from their Ecuadorian counterparts without
actually leaving western Mexico
(D) Whether metal tools were used in the seventh‐
century settlements in western Mexico
(E) Whether any of the techniques used in the
manufacture of the metal rings found in western
Mexico are still practiced among artisans in
Ecuador today
70. Following several years of declining advertising sales,
the Greenville Times reorganized its advertising
sales force. Before reorganization, the sales force
was organized geographically, with some sales
representatives concentrating on city‐center businesses
and others concentrating on different outlying regions.
The reorganization attempted to increase the sales
representatives’ knowledge of clients’ businesses by
having each sales representative deal with only one
type of industry or of retailing. After the reorganization,
revenue from advertising sales increased.
In assessing whether the improvement in advertising
sales can properly be attributed to the reorganization,
it would be most helpful to find out which of the
following?
(A) What proportion of the total revenue of the
Greenville Times is generated by advertising
sales?
(B) Has the circulation of the Greenville Times
increased substantially in the last two years?
(C) Among all the types of industry and retailing
that use the Greenville Times as an advertising
vehicle, which type accounts for the largest
proportion of the newspaper’s advertising sales?
(D) Do any clients of the sales representatives of
the Greenville Times have a standing order with
the Times for a fixed amount of advertising per
month?
(E) Among the advertisers in the Greenville Times,
are there more types of retail business or more
types of industrial business?
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3.2 Diagnostic Test Verbal Questions
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71. Motorists in a certain country frequently complain
that traffic congestion is much worse now than it was
20 years ago. No real measure of how much traffic
congestion there was 20 years ago exists, but the
motorists’ complaints are almost certainly unwarranted.
The country’s highway capacity has tripled in the last
twenty years, thanks to a vigorous highway construction
program, whereas the number of automobiles registered
in the country has increased by only 75 percent.
Which of the following, if true, most seriously weakens
the argument?
(A) Most automobile travel is local, and the networks
of roads and streets in the country’s settled
areas have changed little over the last 20 years.
(B) Gasoline prices are high, and miles traveled per
car per year have not changed much over the
last 20 years.
(C) The country’s urban centers have well‐developed
public transit systems that carry most of the
people who commute into those centers.
(D) The average age of automobiles registered in the
country is lower now than it was 20 years ago.
(E) Radio stations have long been broadcasting
regular traffic reports that inform motorists
about traffic congestion.
72. The percentage of households with an annual income
of more than $40,000 is higher in Merton County
than in any other county. However, the percentage of
households with an annual income of $60,000 or more
is higher in Sommer County.
If the statements above are true, which of the following
must also be true?
(A) The percentage of households with an annual
income of $80,000 is higher in Sommer County
than in Merton County.
(B) Merton County has the second highest
percentage of households with an annual income
of $60,000 or more.
(C) Some households in Merton County have an
annual income between $40,000 and $60,000.
(D) The number of households with an annual income
of more than $40,000 is greater in Merton
County than in Sommer County.
(E) Average annual household income is higher in
Sommer County than in Merton County.
73. Tiger beetles are such fast runners that they can
capture virtually any nonflying insect. However,
when running toward an insect, a tiger beetle will
intermittently stop and then, a moment later, resume
its attack. Perhaps the beetles cannot maintain their
pace and must pause for a moment’s rest; but an
alternative hypothesis is that while running, tiger
beetles are unable to adequately process the resulting
rapidly changing visual information and so quickly go
blind and stop.
Which of the following, if discovered in experiments
using artificially moved prey insects, would support
one of the two hypotheses and undermine the other?
(A) When a prey insect is moved directly toward
a beetle that has been chasing it, the beetle
immediately stops and runs away without its
usual intermittent stopping.
(B) In pursuing a swerving insect, a beetle alters
its course while running and its pauses become
more frequent as the chase progresses.
(C) In pursuing a moving insect, a beetle usually
responds immediately to changes in the insect’s
direction, and it pauses equally frequently
whether the chase is up or down an incline.
(D) If, when a beetle pauses, it has not gained on the
insect it is pursuing, the beetle generally ends its
pursuit.
(E) The faster a beetle pursues an insect fleeing
directly away from it, the more frequently the
beetle stops.
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74. Guillemots are birds of Arctic regions. They feed on
fish that gather beneath thin sheets of floating ice,
and they nest on nearby land. Guillemots need 80
consecutive snow‐free days in a year to raise their
chicks, so until average temperatures in the Arctic
began to rise recently, the guillemots’ range was
limited to the southernmost Arctic coast. Therefore,
if the warming continues, the guillemots’ range will
probably be enlarged by being extended northward
along the coast.
Which of the following, if true, most seriously weakens
the argument?
(A) Even if the warming trend continues, there will
still be years in which guillemot chicks are killed
by an unusually early snow.
(B) If the Arctic warming continues, guillemots’
current predators are likely to succeed in
extending their own range farther north.
(C) Guillemots nest in coastal areas, where
temperatures are generally higher than in inland
areas.
(D) If the Arctic warming continues, much of the thin
ice in the southern Arctic will disappear.
(E) The fish that guillemots eat are currently
preyed on by a wider variety of predators in
the southernmost Arctic regions than they are
farther north.
75. Some batches of polio vaccine used around 1960
were contaminated with SV40, a virus that in monkeys
causes various cancers. Some researchers now
claim that this contamination caused some cases of
a certain cancer in humans, mesothelioma. This claim
is not undercut by the fact that a very careful survey
made in the 1960s of people who had received the
contaminated vaccine found no elevated incidence of
any cancer, since ____________.
(A) most cases of mesothelioma are caused by
exposure to asbestos
(B) in some countries, there was no contamination
of the vaccine
(C) SV40 is widely used in laboratories to produce
cancers in animals
(D) mesotheliomas take several decades to develop
(E) mesothelioma was somewhat less common in
1960 than it is now
76. Gortland has long been narrowly self‐sufficient in
both grain and meat. However, as per capita income
in Gortland has risen toward the world average, per
capita consumption of meat has also risen toward the
world average, and it takes several pounds of grain
to produce one pound of meat. Therefore, since per
capita income continues to rise, whereas domestic
grain production will not increase, Gortland will soon
have to import either grain or meat or both.
Which of the following is an assumption on which the
argument depends?
(A) The total acreage devoted to grain production in
Gortland will soon decrease.
(B) Importing either grain or meat will not result in
a significantly higher percentage of Gortlanders’
incomes being spent on food than is currently
the case.
(C) The per capita consumption of meat in Gortland
is increasing at roughly the same rate across all
income levels.
(D) The per capita income of meat producers in
Gortland is rising faster than the per capita
income of grain producers.
(E) People in Gortland who increase their
consumption of meat will not radically decrease
their consumption of grain.
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3.2 Diagnostic Test Verbal Questions
33
77. The Hazelton coal‐processing plant is a major employer
in the Hazelton area, but national environmental
regulations will force it to close if it continues to use
old, polluting processing methods. However, to update
the plant to use newer, cleaner methods would be so
expensive that the plant will close unless it receives
the tax break it has requested. In order to prevent a
major increase in local unemployment, the Hazelton
government is considering granting the plant’s request.
Which of the following would be most important for
the Hazelton government to determine before deciding
whether to grant the plant’s request?
(A) Whether the company that owns the plant would
open a new plant in another area if the present
plant were closed
(B) Whether the plant would employ far fewer
workers when updated than it does now
(C) Whether the level of pollutants presently being
emitted by the plant is high enough to constitute
a health hazard for local residents
(D) Whether the majority of the coal processed by
the plant is sold outside the Hazelton area
(E) Whether the plant would be able to process more
coal when updated than it does now
78. A physically active lifestyle has been shown to help
increase longevity. In the Wistar region of Bellaria,
the average age at death is considerably higher than
in any other part of the country. Wistar is the only
mountainous part of Bellaria. A mountainous terrain
makes even such basic activities as walking relatively
strenuous; it essentially imposes a physically active
lifestyle on people. Clearly, this circumstance explains
the long lives of people in Wistar.
Which of the following, if true, most seriously weakens
the argument?
(A) In Bellaria all medical expenses are paid by the
government, so that personal income does
not affect the quality of health care a person
receives.
(B) The Wistar region is one of Bellaria’s least
populated regions.
(C) Many people who live in the Wistar region have
moved there in middle age or upon retirement.
(D) The many opportunities for hiking, skiing,
and other outdoor activities that Wistar’s
mountains offer make it a favorite destination for
vacationing Bellarians.
(E) Per capita spending on recreational activities is
no higher in Wistar than it is in other regions of
Bellaria.
79. Cheever College offers several online courses via
remote computer connection, in addition to traditional
classroom‐based courses. A study of student
performance at Cheever found that, overall, the
average student grade for online courses matched
that for classroom‐based courses. In this calculation of
the average grade, course withdrawals were weighted
as equivalent to a course failure, and the rate of
withdrawal was much lower for students enrolled in
classroom‐based courses than for students enrolled in
online courses.
If the statements above are true, which of the following
must also be true of Cheever College?
(A) Among students who did not withdraw, students
enrolled in online courses got higher grades, on
average, than students enrolled in classroom‐
based courses.
(B) The number of students enrolled per course
at the start of the school term is much higher,
on average, for the online courses than for the
classroom‐based courses.
(C) There are no students who take both an online
and a classroom‐based course in the same
school term.
(D) Among Cheever College students with the best
grades, a significant majority take online, rather
than classroom‐based, courses.
(E) Courses offered online tend to deal with subject
matter that is less challenging than that of
classroom‐based courses.
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80. For years the beautiful Renaissance buildings in Palitito
have been damaged by exhaust from the many tour
buses that come to the city. There has been little
parking space, so most buses have idled at the curb
during each stop on their tour, and idling produces as
much exhaust as driving. The city has now provided
parking that accommodates a third of the tour buses,
so damage to Palitito’s buildings from the buses’
exhaust will diminish significantly.
Which of the following, if true, most strongly supports
the argument?
(A) The exhaust from Palitito’s few automobiles is
not a significant threat to Palitito’s buildings.
(B) Palitito’s Renaissance buildings are not
threatened by pollution other than engine
exhaust.
(C) Tour buses typically spend less than one‐quarter
of the time they are in Palitito transporting
passengers from one site to another.
(D) More tourists come to Palitito by tour bus than
by any other single means of transportation.
(E) Some of the tour buses that are unable to
find parking drive around Palitito while their
passengers are visiting a site.
81. During the 1980s and 1990s, the annual number of
people who visited the Sordellian Mountains increased
continually, and many new ski resorts were built. Over
the same period, however, the number of visitors to
ski resorts who were caught in avalanches decreased,
even though there was no reduction in the annual
number of avalanches in the Sordellian Mountains.
Which of the following, if true in the Sordellian
Mountains during the 1980s and 1990s, most helps to
explain the decrease?
(A) Avalanches were most likely to happen when
a large new snowfall covered an older layer of
snow.
(B) Avalanches destroyed at least some buildings in
the Sordellian Mountains in every year.
(C) People planning new ski slopes and other resort
facilities used increasingly accurate information
about which locations are likely to be in the path
of avalanches.
(D) The average length of stay for people visiting the
Sordellian Mountains increased slightly.
(E) Construction of new ski resorts often led to the
clearing of wooded areas that had helped to
prevent avalanches.
82. A year ago, Dietz Foods launched a yearlong
advertising campaign for its canned tuna. Last year
Dietz sold 12 million cans of tuna compared to the
10 million sold during the previous year, an increase
directly attributable to new customers brought in
by the campaign. Profits from the additional sales,
however, were substantially less than the cost of the
advertising campaign. Clearly, therefore, the campaign
did nothing to further Dietz’s economic interests.
Which of the following, if true, most seriously weakens
the argument?
(A) Sales of canned tuna account for a relatively
small percentage of Dietz Foods’ profits.
(B) Most of the people who bought Dietz’s canned
tuna for the first time as a result of the campaign
were already loyal customers of other Dietz
products.
(C) A less expensive advertising campaign
would have brought in significantly fewer new
customers for Dietz’s canned tuna than did the
campaign Dietz Foods launched last year.
(D) Dietz made money on sales of canned tuna last
year.
(E) In each of the past five years, there was a steep,
industry‐wide decline in sales of canned tuna.
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35
3.2 Diagnostic Test Verbal Questions
83. Unlike the buildings in Mesopotamian cities, which
were arranged haphazardly, the same basic plan was
followed for all cities of the Indus Valley: with houses
laid out on a north‐south, east‐west grid, and houses
and walls were built of standard‐size bricks.
(A) the buildings in Mesopotamian cities, which were
arranged haphazardly, the same basic plan was
followed for all cities of the Indus Valley: with
houses
(B) the buildings in Mesopotamian cities, which were
haphazard in arrangement, the same basic plan
was used in all cities of the Indus Valley: houses
were
(C) the arrangement of buildings in Mesopotamian
cities, which were haphazard, the cities of the
Indus Valley all followed the same basic plan:
houses
(D) Mesopotamian cities, in which buildings were
arranged haphazardly, the cities of the Indus
Valley all followed the same basic plan: houses
were
(E) Mesopotamian cities, which had buildings that
were arranged haphazardly, the same basic plan
was used for all cities in the Indus Valley: houses
that were
84. New data from United States Forest Service ecologists
show that for every dollar spent on controlled small‐
scale burning, forest thinning, and the training of
fire‐management personnel, it saves seven dollars that
would not be spent on having to extinguish big fires.
(A) that for every dollar spent on controlled small‐
scale burning, forest thinning, and the training
of fire‐management personnel, it saves seven
dollars that would not be spent on having to
extinguish
(B) that for every dollar spent on controlled small‐
scale burning, forest thinning, and the training
of fire‐management personnel, seven dollars
are saved that would have been spent on
extinguishing
(C) that for every dollar spent on controlled small‐
scale burning, forest thinning, and the training of
fire‐management personnel saves seven dollars
on not having to extinguish
(D) for every dollar spent on controlled small‐scale
burning, forest thinning, and the training of
fire‐management personnel, that it saves seven
dollars on not having to extinguish
(E) for every dollar spent on controlled small‐scale
burning, forest thinning, and the training of
fire‐management personnel, that seven dollars
are saved that would not have been spent on
extinguishing
Sentence Correction
Each of the sentence correction questions presents a sentence, part or all of which is underlined.
Beneath the sentence you will find five ways of phrasing the underlined part. The first of these repeats
the original; the other four are different. Follow the requirements of standard written English to choose
your answer, paying attention to grammar, word choice, and sentence construction. Select the answer
that produces the most effective sentence; your answer should make the sentence clear, exact, and free
of grammatical error. It should also minimize awkwardness, ambiguity, and redundancy.
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GMAT® Official Guide 2018
36
85. Like the grassy fields and old pastures that the
upland sandpiper needs for feeding and nesting
when it returns in May after wintering in the Argentine
Pampas, the sandpipers vanishing in the northeastern
United States is a result of residential and industrial
development and of changes in farming practices.
(A) the sandpipers vanishing in the northeastern
United States is a result of residential and
industrial development and of changes in
(B) the bird itself is vanishing in the northeastern
United States as a result of residential and
industrial development and of changes in
(C) that the birds themselves are vanishing in the
northeastern United States is due to residential
and industrial development and changes to
(D) in the northeastern United States, sandpipers’
vanishing due to residential and industrial
development and to changes in
(E) in the northeastern United States, the
sandpipers’ vanishing, a result of residential and
industrial development and changing
86. The results of two recent unrelated studies support the
idea that dolphins may share certain cognitive abilities
with humans and great apes; the studies indicate
dolphins as capable of recognizing themselves in
mirrors—an ability that is often considered a sign of
self‐awareness—and to grasp spontaneously the mood
or intention of humans.
(A) dolphins as capable of recognizing themselves in
mirrors—an ability that is often considered a sign
of self‐awareness—and to grasp spontaneously
(B) dolphins’ ability to recognize themselves in
mirrors—an ability that is often considered as a
sign of self‐awareness—and of spontaneously
grasping
(C) dolphins to be capable of recognizing
themselves in mirrors—an ability that is often
considered a sign of self‐awareness—and to
grasp spontaneously
(D) that dolphins have the ability of recognizing
themselves in mirrors—an ability that is often
considered as a sign of self‐awareness—and
spontaneously grasping
(E) that dolphins are capable of recognizing
themselves in mirrors—an ability that is often
considered a sign of self‐awareness—and of
spontaneously grasping
87. According to scholars, the earliest writing was
probably not a direct rendering of speech, but was
more likely to begin as a separate and distinct
symbolic system of communication, and only later
merged with spoken language.
(A) was more likely to begin as
(B) more than likely began as
(C) more than likely beginning from
(D) it was more than likely begun from
(E) it was more likely that it began
88. In 1995 Richard Stallman, a well‐known critic of the
patent system, testified in Patent Office hearings that, to
test the system, a colleague of his had managed to win
a patent for one of Kirchhoff’s laws, an observation about
electric current first made in 1845 and now included in
virtually every textbook of elementary physics.
(A) laws, an observation about electric current first
made in 1845 and
(B) laws, which was an observation about electric
current first made in 1845 and it is
(C) laws, namely, it was an observation about
electric current first made in 1845 and
(D) laws, an observation about electric current first
made in 1845, it is
(E) laws that was an observation about electric
current, first made in 1845, and is
89. Excavators at the Indus Valley site of Harappa in
eastern Pakistan say the discovery of inscribed
shards dating to circa 2800–2600 B.C. indicate their
development of a Harappan writing system, the use
of inscribed seals impressed into clay for marking
ownership, and the standardization of weights for trade
or taxation occurred many decades, if not centuries,
earlier than was previously believed.
(A) indicate their development of a Harappan writing
system, the use of
(B) indicate that the development of a Harappan
writing system, using
(C) indicates that their development of a Harappan
writing system, using
(D) indicates the development of a Harappan writing
system, their use of
(E) indicates that the development of a Harappan
writing system, the use of
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3.2 Diagnostic Test Verbal Questions
37
90. The Supreme Court has ruled that public universities
can collect student activity fees even with students’
objections to particular activities, so long as the
groups they give money to will be chosen without
regard to their views.
(A) with students’ objections to particular activities,
so long as the groups they give money to will be
(B) if they have objections to particular activities and
the groups that are given the money are
(C) if they object to particular activities, but the
groups that the money is given to have to be
(D) from students who object to particular activities,
so long as the groups given money are
(E) though students have an objection to particular
activities, but the groups that are given the
money be
91. Despite the increasing number of women graduating
from law school and passing bar examinations, the
proportion of judges and partners at major law firms
who are women have not risen to a comparable extent.
(A) the proportion of judges and partners at major
law firms who are women have not risen to a
comparable extent
(B) the proportion of women judges and partners at
major law firms have not risen comparably
(C) the proportion of judges and partners at
major law firms who are women has not risen
comparably
(D) yet the proportion of women judges and partners
at major law firms has not risen to a comparable
extent
(E) yet the proportion of judges and partners at
major law firms who are women has not risen
comparably
92. Seldom more than 40 feet wide and 12 feet deep,
but it ran 363 miles across the rugged wilderness
of upstate New York, the Erie Canal connected the
Hudson River at Albany to the Great Lakes at Buffalo,
providing the port of New York City with a direct water
link to the heartland of the North American continent.
(A) Seldom more than 40 feet wide and 12 feet
deep, but it ran 363 miles across the rugged
wilderness of upstate New York, the Erie Canal
connected
(B) Seldom more than 40 feet wide or 12 feet
deep but running 363 miles across the rugged
wilderness of upstate New York, the Erie Canal
connected
(C) It was seldom more than 40 feet wide and
12feet deep, and ran 363 miles across the
rugged wilderness of upstate New York, but the
Erie Canal, connecting
(D) The Erie Canal was seldom more than 40 feet
wide or 12 feet deep and it ran 363 miles across
the rugged wilderness of upstate New York,
which connected
(E) The Erie Canal, seldom more than 40 feet wide
and 12 feet deep, but running 363 miles across
the rugged wilderness of upstate New York,
connecting
93. In 1923, the Supreme Court declared a minimum wage
for women and children in the District of Columbia
as unconstitutional, and ruling that it was a form of
price‐fixing and, as such, an abridgment of the right of
contract.
(A) the Supreme Court declared a minimum wage
for women and children in the District of
Columbia as unconstitutional, and
(B) the Supreme Court declared as unconstitutional
a minimum wage for women and children in the
District of Columbia, and
(C) the Supreme Court declared unconstitutional a
minimum wage for women and children in the
District of Columbia,
(D) a minimum wage for women and children
in the District of Columbia was declared
unconstitutional by the Supreme Court,
(E) when the Supreme Court declared a minimum
wage for women and children in the District of
Columbia as unconstitutional,
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GMAT® Official Guide 2018
38
94. Researchers have found that individuals who have been
blind from birth, and who thus have never seen anyone
gesture, nevertheless make hand motions when
speaking just as frequently and in virtually the same
way as sighted people do, and that they will gesture
even when conversing with another blind person.
(A) who thus have never seen anyone gesture,
nevertheless make hand motions when speaking
just as frequently and in virtually the same way
as sighted people do, and that they will gesture
(B) who thus never saw anyone gesturing,
nevertheless make hand motions when speaking
just as frequent and in virtually the same way as
sighted people did, and that they will gesture
(C) who thus have never seen anyone gesture,
nevertheless made hand motions when speaking
just as frequently and in virtually the same way
as sighted people do, as well as gesturing
(D) thus never having seen anyone gesture,
nevertheless made hand motions when speaking
just as frequent and in virtually the same way as
sighted people did, as well as gesturing
(E) thus never having seen anyone gesture,
nevertheless to make hand motions when
speaking just as frequently and in virtually the
same way as sighted people do, and to gesture
95. Like embryonic germ cells, which are cells that
develop early in the formation of the fetus and that
later generate eggs or sperm, embryonic stem cells
have the ability of developing themselves into different
kinds of body tissue.
(A) embryonic stem cells have the ability of
developing themselves into different kinds of
body tissue
(B) embryonic stem cells have the ability to develop
into different kinds of body tissue
(C) in embryonic stem cells there is the ability to
develop into different kinds of body tissue
(D) the ability to develop themselves into different
kinds of body tissue characterizes embryonic
stem cells
(E) the ability of developing into different kinds of
body tissue characterizes embryonic stem cells
96. Critics contend that the new missile is a weapon
whose importance is largely symbolic, more a tool for
manipulating people’s perceptions than to fulfill a real
military need.
(A) for manipulating people’s perceptions than to
fulfill
(B) for manipulating people’s perceptions than for
fulfilling
(C) to manipulate people’s perceptions rather than
that it fulfills
(D) to manipulate people’s perceptions rather than
fulfilling
(E) to manipulate people’s perceptions than for
fulfilling
97. As an actress and, more importantly, as a teacher
of acting, Stella Adler was one of the most influential
artists in the American theater, who trained several
generations of actors including Marlon Brando and
Robert De Niro.
(A) Stella Adler was one of the most influential
artists in the American theater, who trained
several generations of actors including
(B) Stella Adler, one of the most influential artists
in the American theater, trained several
generations of actors who include
(C) Stella Adler was one of the most influential
artists in the American theater, training several
generations of actors whose ranks included
(D) one of the most influential artists in the American
theater was Stella Adler, who trained several
generations of actors including
(E) one of the most influential artists in the American
theater, Stella Adler, trained several generations
of actors whose ranks included
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3.2 Diagnostic Test Verbal Questions
39
98. By developing the Secure Digital Music Initiative, the
recording industry associations of North America,
Japan, and Europe hope to create a standardized way
of distributing songs and full‐length recordings on the
Internet that will protect copyright holders and foil the
many audio pirates who copy and distribute digital
music illegally.
(A) of distributing songs and full‐length recordings
on the Internet that will protect copyright holders
and foil the many audio pirates who copy and
distribute
(B) of distributing songs and full‐length recordings
on the Internet and to protect copyright holders
and foiling the many audio pirates copying and
distributing
(C) for distributing songs and full‐length recordings
on the Internet while it protects copyright holders
and foils the many audio pirates who copy and
distribute
(D) to distribute songs and full‐length recordings
on the Internet while they will protect copyright
holders and foil the many audio pirates copying
and distributing
(E) to distribute songs and full‐length recordings on
the Internet and it will protect copyright holders
and foiling the many audio pirates who copy and
distribute
99. Whereas a ramjet generally cannot achieve high
speeds without the initial assistance of a rocket, high
speeds can be attained by scramjets, or supersonic
combustion ramjets, in that they reduce airflow
compression at the entrance of the engine and letting
air pass through at supersonic speeds.
(A) high speeds can be attained by scramjets, or
supersonic combustion ramjets, in that they
reduce
(B) that high speeds can be attained by scramjets,
or supersonic combustion ramjets, is a result of
their reducing
(C) the ability of scramjets, or supersonic
combustion ramjets, to achieve high speeds is
because they reduce
(D) scramjets, or supersonic combustion ramjets,
have the ability of attaining high speeds when
reducing
(E) scramjets, or supersonic combustion ramjets,
can attain high speeds by reducing
100. It will not be possible to implicate melting sea ice in
the coastal flooding that many global warming models
have projected: just like a glass of water that will not
overflow due to melting ice cubes, so melting sea ice
does not increase oceanic volume.
(A) like a glass of water that will not overflow due to
melting ice cubes,
(B) like melting ice cubes that do not cause a glass
of water to overflow,
(C) a glass of water will not overflow because of
melting ice cubes,
(D) as melting ice cubes that do not cause a glass
of water to overflow,
(E) as melting ice cubes do not cause a glass of
water to overflow,
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GMAT® Official Guide 2018
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3.3 Quantitative and Verbal Answer Keys
Quantitative Verbal
1. A
2. D
3. E
4. B
5. B
6. A
7. E
8. E
9. D
10. C
11. C
12. C
13. E
14. B
15. C
16. E
17. D
18. A
19. A
20. B
21. D
22. E
23. B
24. C
25. E
26. E
27. E
28. E
29. E
30. A
31. D
32. C
33. D
34. C
35. D
36. B
37. A
38. B
39. E
40. D
41. C
42. C
43. B
44. A
45. D
46. E
47. D
48. C
49. E
50. C
51. B
52. A
53. D
54. C
55. A
56. A
57. B
58. A
59. B
60. D
61. B
62. A
63. E
64. C
65. E
66. B
67. E
68. C
69. A
70. B
71. A
72. C
73. B
74. D
75. D
76. E
77. B
78. C
79. A
80. C
81. C
82. E
83. D
84. B
85. B
86. E
87. B
88. A
89. E
90. D
91. C
92. B
93. C
94. A
95. B
96. B
97. C
98. A
99. E
100. E
3.4 Interpretive Guide
e following table provides a guide for interpreting your score, on the basis of the number of questions
you got right.
Interpretive Guide
Excellent Above Average Average Below Average
Problem Solving 19–24 16–18 10–15 0–9
Data Suciency 19–24 16–18 10–15 0–9
Reading Comprehension 16–17 14–15 9–13 0–8
Critical Reasoning 14–17 9–13 6–8 0–5
Sentence Correction 16–18 11–15 8–10 0–7
Remember, you should not compare the number of questions you got right in each section. Instead, you
should compare how your response rated in each section.
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41
3.5 Diagnostic Test Quantitative Answer Explanations
1. Last month a certain music club offered a discount
to preferred customers. After the first compact disc
purchased, preferred customers paid $3.99 for each
additional compact disc purchased. If a preferred
customer purchased a total of 6 compact discs and
paid $15.95 for the first compact disc, then the dollar
amount that the customer paid for the 6 compact
discs is equivalent to which of the following?
(A) 5(4.00) + 15.90
(B) 5(4.00) + 15.95
(C) 5(4.00) + 16.00
(D) 5(4.00 – 0.01) + 15.90
(E) 5(4.00 – 0.05) + 15.95
Arithmetic Operations on rational numbers
e cost of the 6 compact discs, with $15.95
for the first one and $3.99 for the other 5 discs,
can be expressed as 5(3.99) + 15.95. It is clear
from looking at the answer choices that some
regrouping of the values is needed because
none of the answer choices uses $3.99 in the
calculation.
If $4.00 is used instead of $3.99, each one of the
5 additional compact discs is calculated at$0.01
too much, and the total cost is 5(0.01)= $0.05
too high. ere is an overage of $0.05 that
must be subtracted from the $15.95, or thus
$15.95– $0.05 = $15.90. erefore, the cost can
be expressed as 5(4.00) + 15.90.
e correct answer is A.
2. The average (arithmetic mean) of the integers from
200 to 400, inclusive, is how much greater than the
average of the integers from 50 to 100, inclusive?
(A) 150
(B) 175
(C) 200
(D) 225
(E) 300
Arithmetic Statistics
In the list of integers from 200 to 400 inclusive,
the middle value is 300. For every integer above
300, there exists an integer below 300 that is the
same distance away from 300; thus the average
of the integers from 200 to 400, inclusive, will be
kept at 300. In the same manner, the average of
the integers from 50 to 100, inclusive, is 75.
e dierence is 300 – 75 = 225.
e correct answer is D.
3. The sequence a1, a2, a3, …, an, … is such that
a
aa
2
nnn
12
=
+
−− for all n ≥ 3. If a3 = 4 and a5 = 20,
what is the value of a6?
(A) 12
(B) 16
(C) 20
(D) 24
(E) 28
3.5 Quantitative Answer Explanations
Problem Solving
The following discussion is intended to familiarize you with the most efficient and effective approaches
to the kinds of problems common to problem solving questions. The particular questions in this chapter
are generally representative of the kinds of quantitative questions you will encounter on the GMAT
exam. Remember that it is the problem solving strategy that is important, not the specific details of a
particular question.
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GMAT® Official Guide 2018
42
Algebra Applied problems
According to this formula, it is necessary to know
the two prior terms in the sequence to determine
the value of a term; that is, it is necessary to know
both
an1−
and
an2−
to find
an
. erefore, to find
a6
,
the values of
a5
and
a4
must be determined. To
find
a4
, let
aa
n5
=
, which makes
aa
n14
=
− and
aa
n23
=
−. en, by substituting the given values
into the formula
aaa
2
n
nn12
=
+
−−
aaa
2
5
43
=
+
=
+a
20 4
2
4 substitute known values
a40 4
4
=+
multiply both sides
a36 4
=
subtract 4 from both sides
en, letting
=aa
n6
, substitute the known values:
aaa
2
6
54
=
+
a20 36
2
6=
+
substitute known values
a56
2
6= simplify
a28
6=
e correct answer is E.
4. Among a group of 2,500 people, 35 percent invest
in municipal bonds, 18 percent invest in oil stocks,
and 7percent invest in both municipal bonds and oil
stocks. If 1 person is to be randomly selected from the
2,500 people, what is the probability that the person
selected will be one who invests in municipal bonds but
NOT in oil stocks?
(A)
9
50
(B)
7
25
(C)
7
20
(D)
21
50
(E)
27
50
Arithmetic Probability
Since there are 2,500 people, 2,500(0.35) = 875
people invest in municipal bonds, and
2,500(0.07) = 175 of those people invest in
both municipal bonds and oil stocks. erefore,
there are 875 – 175 = 700 people who invest in
municipal bonds but not in oil stocks. Probability
of an event =
Number of desiredoutcomes
Totalnumberofoutcomesthatcan occur
.
Probability of investing in municipal bonds but
not in oil stocks
700
2,500
7
25
==
e correct answer is B.
5. A closed cylindrical tank contains 36π cubic feet of
water and is filled to half its capacity. When the tank
is placed upright on its circular base on level ground,
the height of the water in the tank is 4 feet. When the
tank is placed on its side on level ground, what is the
height, in feet, of the surface of the water above the
ground?
(A) 2
(B) 3
(C) 4
(D) 6
(E) 9
Geometry Volume
Since the cylinder is half full, it will be filled to
half its height, whether it is upright or on its side.
When the cylinder is on its side, half its height is
equal to its radius.
![](asset-32.png)
43
3.5 Diagnostic Test Quantitative Answer Explanations
water level
radius = half the height
Using the information about the volume of water
in the upright cylinder, solve for this radius to
determine the height of the water when the
cylinder is on its side.
Vrh
2
π
=
volume = (
π
)(radius2)(height)
rh36
2
ππ
=
known volume of water is 36
π
r36 (4)
2
= substitute 4 for h; divide both
sides by
π
r92
=
solve for r
3 = r radius = height of the water
in the cylinder on its side
e correct answer is B.
6. A marketing firm determined that, of 200 households
surveyed, 80 used neither Brand A nor Brand B soap,
60 used only Brand A soap, and for every household
that used both brands of soap, 3 used only Brand B
soap. How many of the 200 households surveyed used
both brands of soap?
(A) 15
(B) 20
(C) 30
(D) 40
(E) 45
Arithmetic Operations on rational numbers
Since it is given that 80 households use neither
Brand A nor Brand B, then 200 – 80 = 120 must
use Brand A, Brand B, or both. It is also given
that 60 households use only Brand A and that
three times as many households use Brand B
exclusively as use both brands. If x is the number
of households that use both Brand A and Brand
B, then 3x use Brand B alone. A Venn diagram
can be helpful for visualizing the logic of the
given information for this item:
Brand A Brand B
60 3x
x
All the sections in the circles can be added up
and set equal to 120, and then the equation can
be solved for x:
xx60 3 120++ =
x60 4 120+=
combine like terms
x460=
subtract 60 from both sides
x15=
divide both sides by 4
e correct answer is A.
7. A certain club has 10 members, including Harry. One
of the 10 members is to be chosen at random to be
the president, one of the remaining 9 members is to
be chosen at random to be the secretary, and one of
the remaining 8 members is to be chosen at random
to be the treasurer. What is the probability that Harry
will be either the member chosen to be the secretary
or the member chosen to be the treasurer?
(A)
1
720
(B)
1
80
(C) 1
10
(D) 1
9
(E)
1
5
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GMAT® Official Guide 2018
44
Arithmetic Probability
Two probabilities must be calculated here: (1) the
probability of Harry’s being chosen for secretary
and (2) the probability of Harry’s being chosen
for treasurer. For any probability, the probability
of an event’s occurring
number of desiredoutcomes
totalnumberofoutcomesthatcan occur
.
(1) If Harry is to be secretary, he first
CANNOT have been chosen for president,
and then he must be chosen for secretary. e
probability that he will be chosen for president is
1
10
, so the probability of his NOT being
chosen for president is
11
10
9
10
−=
. en, the
probability of his being chosen for secretary is
1
9
.
Once he is chosen, the probability that he will be
selected for treasurer is 0, so the probability that
he will NOT be selected for treasurer is 1 – 0 = 1.
us, the probability that Harry will be chosen
for secretary is 9
10
1
9
11
10
()
=
(2) If Harry is to be treasurer, he needs to be
NOT chosen for president, then NOT chosen for
secretary, and then finally chosen for treasurer.
e probability that he will NOT be chosen for
president is again
11
10
9
10
−=
. e probability of
his NOT being chosen for secretary is
11
9
8
9
−=
.
e probability of his being chosen for treasurer
is
1
8
, so the probability that Harry will be chosen
for treasurer is 9
10
8
9
1
8
1
10
=.
(3) So, finally, the probability of Harry’s being
chosen as either secretary or treasurer is thus
1
10
1
10
2
10
1
5
+==.
e correct answer is E.
8. If a certain toy store’s revenue in November was
2
5
of its revenue in December and its revenue in
January was
1
4 of its revenue in November, then the
store’s revenue in December was how many times the
average (arithmetic mean) of its revenues in November
and January?
(A)
1
4
(B) 1
2
(C)
2
3
(D) 2
(E) 4
Arithmetic Statistics
Let n be the store’s revenue in November, d be the
store’s revenue in December, and j be the store’s
revenue in January. e information from the
problem can be expressed as
nd
2
5
= and
jn
1
4
=.
Substituting d
2
5
for n in the second equation
gives jdd
1
4
2
5
1
10
=
=. en, the average of the
revenues in November and January can be found
by using these values in the formula
averag
e
sumofvalues
number of values
=, as follows:
=+=+
==
dd dd d
averag
e
2
5
1
10
2
4
10
1
10
2
5
10
2
dd
1
2
1
2
1
4
=
Solve for the store’s revenue in December by
multiplying both sides of this equation by 4:
daverage
1
4
=
d4(average) =
us, the store’s revenue in December was
4times its average revenue in November and
January.
e correct answer is E.
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45
3.5 Diagnostic Test Quantitative Answer Explanations
9. A researcher computed the mean, the median, and the
standard deviation for a set of performance scores.
If 5 were to be added to each score, which of these
three statistics would change?
(A) The mean only
(B) The median only
(C) The standard deviation only
(D) The mean and the median
(E) The mean and the standard deviation
Arithmetic Statistics
If 5 were added to each score, the mean would
go up by 5, as would the median. However, the
spread of the values would remain the same,
simply centered around a new value. So, the
standard deviation would NOT change.
e correct answer is D.
x°
v°w°
y°
z°
10. In the figure shown, what is the value of
vxyzw++++
?
(A) 45
(B) 90
(C) 180
(D) 270
(E) 360
Geometry Angles and their measure
In the following figure, the center section of the
star is a pentagon.
x°
v°w°
y°
z°
a°
b°
c°d°
e°
e sum of the interior angles of any polygon is
180(n – 2), where n is the number of sides. us,
a + b + c + d + e = 180(5 – 2) = 180(3) = 540.
Each of the interior angles of the pentagon defines
a triangle with two of the angles at the points of
the star. is gives the following five equations:
axz
bv y
cx
w
dv
z
eyw
180
180
180
180
180
++=
++=
++ =
++=
++ =
Summing these 5 equations gives:
abcdevxyzw22222 900.+++++++++=
Substituting 540 for
abcde++++
gives:
vx yw540 2222 900.++++ =
From this:
vx yzw22222 360++++ =
subtract 540 from
both sides
vx yzw2( ) 360++++ =
factor out 2 on
the left side
vx yzw180++++ =
divide both sides
by 2
e correct answer is C.
11. Of the three‐digit integers greater than 700, how many
have two digits that are equal to each other and the
remaining digit different from the other two?
(A) 90
(B) 82
(C) 80
(D) 45
(E) 36
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46
Arithmetic Properties of numbers
In three‐digit integers, there are three pairs of
digits that can be the same while the other digit
is dierent: tens and ones, hundreds and tens,
and hundreds and ones. In each of these pairs,
there are 9 options for having the third digit be
dierent from the other two. e single exception
to this is in the 700–799 set, where the number
700 cannot be included because the problem
calls for integers “greater than 700.” So, in the
700–799 set, there are only 8 options for when
the tens and ones are the same. is is shown in
the table below.
Number of digits available for the third digit
when two given digits are the same
Same 701–799 800–899 900–999
tens and ones 8 9 9
hundreds and tens 9 9 9
hundreds and ones 9 9 9
us, of the three‐digit integers greater than
700, there are 9(9) – 1 = 80 numbers that have
two digits that are equal to each other when the
remaining digit is dierent from these two.
e correct answer is C.
12. Positive integer y is 50 percent of 50 percent of
positive integer x, and y percent of x equals 100. What
is the value of x?
(A) 50
(B) 100
(C) 200
(D) 1,000
(E) 2,000
Arithmetic; Algebra Percents
Simultaneous equations
Because y is a positive integer, y percent is
notated as
y
100
. According to the problem,
yx
y
x0.50(0.50)and
100 100
=
=.
e first equation simplifies to y = 0.25x, and
multiplying the second equation by 100 gives
xy = 10,000.
Substituting the simplified first equation into this
second equation gives:
=xx(0.25) 10,000
0.25x2 = 10,000 simplify left side
x2 = 40,000 divide both sides by 0.25
x = 200 solve for the value of x
e correct answer is C.
13. If s and t are positive integers such that
s
t64.12
=,
which of the following could be the remainder when s
is divided by t?
(A) 2
(B) 4
(C) 8
(D) 20
(E) 45
Arithmetic Operations on rational numbers
By using a long division model, it can be seen
that the remainder after dividing s by t is s – 64t:
ts
t64
64
−
st64−
en, the given equation can be written as
64.12t = s. By splitting portions of t into its
integer multiple and its decimal multiple, this
becomes 64t + 0.12t = s, or 0.12t = s – 64t, which
is the remainder. So, 0.12t = remainder. Test the
answer choices to find the situation in which t is
an integer.
A 0.12t = 2 or t = 16.67 NOT an integer
B 0.12t = 4 or t = 33.33 NOT an integer
C 0.12t = 8 or t = 66.67 NOT an integer
D 0.12t = 20 or t = 166.67 NOT an integer
E 0.12t = 45 or t = 375 INTEGER
e correct answer is E.
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47
3.5 Diagnostic Test Quantitative Answer Explanations
14. Of the 84 parents who attended a meeting at a school,
35 volunteered to supervise children during the school
picnic and 11 volunteered both to supervise children
during the picnic and to bring refreshments to the
picnic. If the number of parents who volunteered
to bring refreshments was 1.5 times the number
of parents who neither volunteered to supervise
children during the picnic nor volunteered to bring
refreshments, how many of the parents volunteered to
bring refreshments?
(A) 25
(B) 36
(C) 38
(D) 42
(E) 45
Arithmetic Operations on rational numbers
Out of the 35 parents who agreed to supervise
children during the school picnic, 11 parents
are also bringing refreshments, so 35 – 11 =24
parents are only supervising children. Let x
be the number of parents who volunteered to
bring refreshments, and let y be the number of
parents who declined to supervise or to bring
refreshments. e fact that the number of parents
who volunteered to bring refreshments is
1.5 times the number who did not volunteer at
all can then be expressed as x = 1.5y. A Venn
diagram, such as the one below, can be helpful in
answering problems of this kind.
Supervise
Bring
Refreshments, x
24
y
11
en, the sum of the sections can be set equal to
the total number of parents at the picnic, and the
equation can be solved for y:
y + 24 + x = 84 sum of sections = total
parents at picnic
y + x = 60 subtract 24 from each side
y = 60 – x subtract x from each side
en, substituting the value 60 – x for y in the
equation x = 1.5y gives the following:
xx=−1560.( )
x = 90 – 1.5x distribute the 1.5
2.5x = 90 add 1.5x to both sides
x = 36 divide both sides by 2.5
e correct answer is B.
15. The product of all the prime numbers less than 20 is
closest to which of the following powers of 10?
(A) 109
(B) 108
(C) 107
(D) 106
(E) 105
Arithmetic Properties of numbers
e prime numbers less than 20 are 2, 3, 5, 7, 11,
13, 17, and 19. eir product is 9,699,690
(arrived at as follows:
2 × 3 × 5 × 7 × 11 × 13 × 17 × 19 = 9,699, 690).
is is closest to 10,000,000 = 107
(10 × 10 × 10 × 10 × 10 × 10 × 10 = 10,000,000).
e correct answer is C.
16. If 32 21then 4−=
+=
xx x,2
(A) 1
(B) 4
(C) 2 − 2x
(D) 4x − 2
(E) 6x − 1
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Algebra Second-degree equations
Work with the equation to create 4x2 on one side.
32 21
−= +
xx
32
21
22
−
()
=+
()
xx
square both sides
32 2221
−=+ +
xx x
24 22−=xx
move all non‐
square‐root terms to
one side (i.e.,
subtract 2x and 1)
12 2
−=
xx
divide both sides by 2
12 2
22
−
()
=
()
xx
square both sides
14 42
2
−+ =xx x
461
2
xx=−
isolate the 4x2 (add
4x and subtract 1
from both sides)
e correct answer is E.
17. If
n
=16
81, what is the value of
n
?
(A) 1
9
(B) 1
4
(C) 4
9
(D)
2
3
(E)
9
2
Arithmetic Operations on radical expressions
Work the problem.
Since
nn
==
==
16
81
4
9
4
9
2
3
,.
then
e correct answer is D.
18. If n is the product of the integers from 1 to 8,
inclusive, how many different prime factors greater
than 1 does n have?
(A) Four
(B) Five
(C) Six
(D) Seven
(E) Eight
Arithmetic Properties of numbers
If n is the product of the integers from 1 to 8,
then its prime factors will be the prime numbers
from 1 to 8. ere are four prime numbers
between 1 and 8: 2, 3, 5, and 7.
e correct answer is A.
19. If k is an integer and 2 < k < 7, for how many different
values of k is there a triangle with sides of lengths 2,
7, and k?
(A) One
(B) Two
(C) Three
(D) Four
(E) Five
Geometry Triangles
In a triangle, the sum of the smaller two sides
must be larger than the largest side.
For k values 3, 4, 5, and 6, the only triangle
possible is 2, 7, and k = 6 because only 2 + 6 > 7.
For k values 3, 4, and 5, the sum of the smaller
two sides is not larger than the third side; thus,
6 is the only possible value of k that satisfies the
conditions.
e correct answer is A.
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49
3.5 Diagnostic Test Quantitative Answer Explanations
20. A right circular cone is inscribed in a hemisphere so
that the base of the cone coincides with the base of
the hemisphere. What is the ratio of the height of the
cone to the radius of the hemisphere?
(A)
31
:
(B) 1:1
(C)
1
2
1:
(D)
21:
(E) 2:1
Geometry Volume
As the diagram below shows, the height of the
cone will be the radius of the hemisphere, so the
ratio is 1:1.
r
e correct answer is B.
21. John deposited $10,000 to open a new savings
account that earned 4 percent annual interest,
compounded quarterly. If there were no other
transactions in the account, what was the amount of
money in John’s account 6 months after the account
was opened?
(A) $10,100
(B) $10,101
(C) $10,200
(D) $10,201
(E) $10,400
Arithmetic Operations on rational numbers
Since John’s account is compounded quarterly, he
receives
1
4
of his annual interest, or 1%, every
3months. is is added to the amount already in
the account to accrue interest for the next quarter.
After 6 months, this process will have occurred
twice, so the amount in John’s account will then be
($10,000)(1.01)(1.01) = $10,000(1.01)2 = $10,201.
e correct answer is D.
22. A container in the shape of a right circular cylinder is
1
2
full of water. If the volume of water in the container
is 36 cubic inches and the height of the container
is 9 inches, what is the diameter of the base of the
cylinder, in inches?
(A) 16
9
π
(B)
4
π
(C) 12
π
(D) 2
π
(E)
4
2
π
Geometry Volume
For a right cylinder, volume = π(radius)2(height).
Since the volume of water is 36 cubic inches and
since this represents
1
2
the container, the water
is occupying
1
2
the container’s height, or
9
1
2
= 4.5 inches. Let r be the radius of the
cylinder.
36 45
2
=
π
r(.)
8
2
=
π
r
divide both sides by 4.5
8
2
π
=r divide both sides by π
8
π
=r take the square root of both sides
22
π
=r simplify the
8
to get the radius
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GMAT® Official Guide 2018
50
en, since the diameter is twice the length of the
radius, the diameter equals
2
22 4242
ππ
π
==.
e correct answer is E.
23. If the positive integer x is a multiple of 4 and the
positive integer y is a multiple of 6, then xy must be a
multiple of which of the following?
I. 8
II. 12
III. 18
(A) II only
(B) I and II only
(C) I and III only
(D) II and III only
(E) I, II, and III
Arithmetic Properties of numbers
e product xy must be a multiple of 4(6) = 24
and any of its factors. Test each alternative.
I.
24
83
= 8 is a factor of 24
MUST be a multiple of 8
II.
24
12 2
= 12 is a factor of 24
MUST be a multiple of 12
III.
24
18
1
1
3
= 18 is NOT a factor of 24
NEED NOT be a multiple of 18
e correct answer is B.
24. Aaron will jog from home at x miles per hour and then
walk back home by the same route at y miles per hour.
How many miles from home can Aaron jog so that he
spends a total of t hours jogging and walking?
(A) xt
y
(B)
xt
xy
+
(C)
xyt
xy
+
(D) xyt
xy
++
(E)
yt
x
t
y
+
−
Algebra Simplifying algebraic expressions
Let j be the number of hours Aaron spends
jogging; then let t – j be the total number of
hours he spends walking. It can be stated that
Aaron jogs a distance of xj miles and walks a
distance of y(t – j) miles. Because Aaron travels
the same route, the miles jogged must equal the
miles walked, and they can be set equal.
xj yt j=−()
set number of miles equal to
each other
xj yt jy=−
distribute the y
xj jy yt+=
add jy to both sides to get all
terms with j to one side
jx yyt()+=
factor out the j
j
yt
xy
=+. divide both sides by x + y
So, the number of hours Aaron spends jogging is
j
yt
xy
=+.
e number of miles he can jog is xj or, by
substitution of this value of j,
x
yt
xy
xyt
xy
+
=+.
e correct answer is C.
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51
3.5 Diagnostic Test Quantitative Answer Explanations
25. If the units digit of integer n is greater than 2, what is
the units digit of n?
(1) The units digit of n is the same as the units digit
of n2.
(2) The units digit of n is the same as the units digit
of n3.
Arithmetic Arithmetic operations
If the units digit of n is greater than 2, then it can
only be the digits 3, 4, 5, 6, 7, 8, or 9.
(1) To solve this problem, it is necessary to
find a digit that is the same as the units digit of
its square. For example, both 43 squared (1,849)
and 303 squared (91,809) have a units digit of 9,
which is dierent from the units digit of 43 and
303. However, 25 squared (625) and 385 squared
(148,225) both have a units digit of 5, and 16 and
226 both have a units digit of 6 and their squares
(256 and 51,076, respectively) do, too. However,
there is no further information to choose between
5 or 6; NOT sufficient.
(2) Once again, 5 and 6 are the only numbers
which, when cubed, will both have a 5 or 6
respectively in their units digits. However, the
information given does not distinguish between
them; NOT sufficient.
Since (1) and (2) together yield the same
information but with no direction as to which
to choose, there is not enough information to
determine the answer.
e correct answer is E;
both statements together are still not sufficient.
26. What is the value of the integer p?
(1) Each of the integers 2, 3, and 5 is a factor of p.
(2) Each of the integers 2, 5, and 7 is a factor of p.
Arithmetic Properties of numbers
(1) ese are factors of p, but it is not clear that
they are the only factors of p; NOT sufficient.
(2) ese are factors of p, but it is not clear that
they are the only factors of p; NOT sufficient.
Taken together, (1) and (2) overlap, but again
there is no clear indication that these are the only
factors of p.
e correct answer is E;
both statements together are still not sufficient.
27. If the length of Wanda’s telephone call was rounded
up to the nearest whole minute by her telephone
company, then Wanda was charged for how many
minutes for her telephone call?
(1) The total charge for Wanda’s telephone call was
$6.50.
(2) Wanda was charged $0.50 more for the first
minute of the telephone call than for each minute
after the first.
Arithmetic Arithmetic operations
(1) is does not give any information as to the
call’s cost per minute; NOT sufficient.
(2) From this, it can be determined only that
the call was longer than one minute and that the
charge for the first minute was $0.50 more than
the charge for each succeeding minute; NOT
sufficient.
Data Sufficiency
The following section on data sufficiency is intended to familiarize you with the most efficient and
effective approaches to the kinds of problems common to data sufficiency. The particular questions in
this chapter are generally representative of the kinds of data sufficiency questions you will encounter
on the GMAT exam. Remember that it is the problem solving strategy that is important, not the specific
details of a particular question.
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Taking (1) and (2) together, the number of
minutes cannot be determined as long as the
cost of each minute after the first is unknown.
For example, if the cost of each minute after the
first minute were $0.40, then the cost of the first
minute would be $0.90. en the total cost of the
other minutes would be $6.50 – $0.90 = $5.60,
and $5.60 ÷ $0.40 would yield 14. In this case,
the time of the call would be 1 + 14 = 15 minutes.
If, however, the cost of each minute after the
first minute were $0.15, then the cost of the first
minute would be $0.65. en $6.50 – $0.65 would
be $5.85, and this in turn, when divided by $0.15,
would yield 39minutes, for a total call length of
40 minutes. More information on the cost of each
minute after the first minute is still needed.
e correct answer is E;
both statements together are still not sufficient.
28. What is the perimeter of isosceles triangle MNP?
(1) MN = 16
(2) NP = 20
Geometry Triangles
e perimeter of a triangle is the sum of all three
sides. In the case of an isosceles triangle, two of
the sides are equal. To determine the perimeter
of this triangle, it is necessary to know both the
length of an equal side and the length of the base
of the triangle.
(1) Only gives the length of one side; NOT
sufficient.
(2) Only gives the length of one side; NOT
sufficient.
Since it is unclear whether MN or NP is one of
the equal sides, it is not possible to determine the
length of the third side or the perimeter of the
triangle. e perimeter could be either
((2)(16)) + 20 = 52 or ((2)(20)) + 16 = 56.
e correct answer is E;
both statements together are still not sufficient.
29. In a survey of retailers, what percent had purchased
computers for business purposes?
(1) 85 percent of the retailers surveyed who owned
their own store had purchased computers for
business purposes.
(2) 40 percent of the retailers surveyed owned their
own store.
Arithmetic Percents
(1) With only this, it cannot be known
what percent of the retailers not owning their
own store had purchased computers, and so it
cannot be known how many retailers purchased
computers overall; NOT sufficient.
(2) While this permits the percent of owners
and nonowners in the survey to be deduced, the
overall percent of retailers who had purchased
computers cannot be determined; NOT sufficient.
Using the information from both (1) and (2),
the percent of surveyed owner‐retailers who had
purchased computers can be deduced, and the
percent of nonowner‐retailers can also be deduced.
However, the information that would permit a
determination of either the percent of nonowner‐
retailers who had purchased computers or the overall
percent of all retailers (both owners and nonowners)
who had purchased computers is still not provided.
e correct answer is E;
both statements together are still not sufficient.
30. The only gift certificates that a certain store sold
yesterday were worth either $100 each or $10 each. If
the store sold a total of 20 gift certificates yesterday,
how many gift certificates worth $10 each did the
store sell yesterday?
(1) The gift certificates sold by the store yesterday
were worth a total of between $1,650 and
$1,800.
(2) Yesterday the store sold more than 15 gift
certificates worth $100 each.
Algebra Applied problems; Simultaneous
equations; Inequalities
Let x represent the number of $100 certificates
sold, and let y represent the number of $10
certificates sold. en the given information can
be expressed as x + y = 20 or thus y = 20 – x. e
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53
3.5 Diagnostic Test Quantitative Answer Explanations
value of the $100 certificates sold is 100x, and the
value of the $10 certificates sold is 10y.
(1) From this, it is known that 100x + 10y >1,650.
Since y = 20 − x, this value can be substituted for y,
and the inequality can be solved for x:
xy100 10 1,650+>
xx100 10(20)1, 650+−>
substitute for y
100x + 200 − 10x > 1,650 distribute
90x + 200 > 1,650 simplify
90x > 1,450 subtract 200 from
both sides
x > 16.1
us, more than 16 of the $100 certificates were
sold. If 17 $100 certificates were sold, then it
must be that 3 $10 certificates were also sold for
a total of $1,730, which satisfies the condition of
being between $1,650 and $1,800. If, however,
18$100 certificates were sold, then it must
be that 2 $10 certificates were sold, and this
totals $1,820, which is more than $1,800 and
fails to satisfy the condition. erefore, 3 of the
$10certificates were sold; SUFFICIENT.
(2) From this it can be known only that the
number of $10 certificates sold was 4 or fewer;
NOT sufficient.
e correct answer is A;
statement 1 alone is sufficient.
31. Is the standard deviation of the set of measurements
x1, x2, x3, x4, …, x20 less than 3?
(1) The variance for the set of measurements is 4.
(2) For each measurement, the difference between
the mean and that measurement is 2.
Arithmetic Statistics
In determining the standard deviation, the
dierence between each measurement and
the mean is squared, and then the squared
dierences are added and divided by the number
of measurements. e quotient is the variance
and the positive square root of the variance is the
standard deviation.
(1) If the variance is 4, then the standard
deviation
==42
, which is less than 3;
SUFFICIENT.
(2) For each measurement, the dierence
between the mean and that measurement is 2.
erefore, the square of each dierence is 4, and
the sum of all the squares is 4 × 20 = 80. e
standard deviation is 80
20 42==
, which is less
than 3; SUFFICIENT.
e correct answer is D;
each statement alone is sufficient.
32. Is the range of the integers 6, 3, y, 4, 5, and x greater
than 9?
(1) y > 3x
(2) y > x > 3
Arithmetic Statistics
e range of a set of integers is equal to the
dierence between the largest integer and the
smallest integer. e range of the set of integers
3, 4, 5, and 6 is 3, which is derived from 6 – 3.
(1) Although it is known that y > 3x, the value
of x is unknown. If, for example, x = 1, then the
value of y would be greater than 3. However, if
x = 2, then the value of y would be greater than
6, and, since 6 would no longer be the largest
integer, the range would be aected. Because the
actual values of x and y are unknown, the value of
the range is also unknown; NOT sufficient.
(2) If x > 3 and y > x, then x could be 4 and
y could be 5. en the range of the 6 integers
would still be 6 – 3 or 3. However, if x were 4 and
y were 15, then the range of the 6 integers would
be 15 – 3, or 12. ere is no means to establish
the values of x and y, beyond the fact that they
both are greater than 3; NOT sufficient.
Taking (1) and (2) together, it is known that
x> 3 and that y > 3x. Since the smallest integer
that x could be is thus 4, then y > 3(4) or y > 12.
erefore, the integer y must be 13 or larger.
When y is equal to 13, the range of the 6 integers
is 13 – 3 = 10, which is larger than 9. As y
increases in value, the value of the range will also
increase.
e correct answer is C;
both statements together are sufficient.
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33. Is
5
25
1?
x2
<
+
(1) <
51
x
(2)
<x0
Algebra Inequalities
Note that
xxx
rs rs+
=
()()
(1) If
51
,then5
25 1
xx2
<<
+
since
=
⋅
=
+
5
25
55
25
5
xx x
22
; SUFFICIENT.
(2) If
x0<
, then
x22+<
add 2 to both sides
55
x
22
<
+ because a < b implies 5a < 5b
5
25
1
x2<
+
divide both sides by 52 = 25;
SUFFICIENT.
e correct answer is D;
each statement alone is sucient.
34. Of the companies surveyed about the skills they
required in prospective employees, 20 percent
required both computer skills and writing skills. What
percent of the companies surveyed required neither
computer skills nor writing skills?
(1) Of those companies surveyed that required
computer skills, half required writing skills.
(2) 45 percent of the companies surveyed required
writing skills but not computer skills.
Arithmetic Percents
e surveyed companies could be placed into one
of the following four categories:
1. Requiring computer skills and requiring
writing skills
2. Requiring computer skills but not requiring
writing skills
3. Not requiring computer skills but requiring
writing skills
4. Not requiring either computer skills or writing
skills
It is given that 20 percent of the surveyed
companies fell into category 1. It is necessary
to determine what percent of the surveyed
companies fell into category 4.
(1) is helps identify the percentage in
category 2. Since
1
2
the companies that required
computer skills also required writing skills (i.e.,
those in category 1), then the other
1
2
of the
companies that required computer skills did not
require writing skills (thus category 2 = category
1). However, this information only establishes
that 20 percent required computer skills, but not
writing skills; NOT sucient.
(2) While this establishes category 3, that
is, that 45 percent required writing skills but
not computer skills, no further information is
available; NOT sucient.
Taking (1) and (2) together, the rst three
categories add up to 85 percent (20 + 20 + 45).
erefore, category 4 would be equal to
100 – 85 = 15 percent of the surveyed companies
required neither computer skills nor writing skills.
e correct answer is C;
both statements together are sucient.
35. What is the value of
wq?+
(1) =−
wq33
3
(2)
+=
wq
55
5
Algebra First- and second-degree equations
(1) If 3q is added to both sides of this equation,
it can be rewritten as
333wq+=
. When each
term is then divided by 3, it yields
wq+=1
;
SUFFICIENT.
(2) When each term in this equation is divided
by 5, it becomes
wq+=1
; SUFFICIENT.
e correct answer is D;
each statement alone is sucient.
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55
3.5 Diagnostic Test Quantitative Answer Explanations
36. If X and Y are points in a plane and X lies inside the
circle C with center O and radius 2, does Y lie inside
circle C?
(1) The length of line segment XY is 3.
(2) The length of line segment OY is 1.5.
Geometry Circles
(1) e maximum distance between two points
that lie on a circle is equal to the diameter, or
2 times the radius. Since the radius of circle C
is 2, the diameter in this case is 4. It cannot be
assumed, however, that X and Y are points on the
diameter; X can lie anywhere within the circle.
When the distance between X and Y is 3, it is still
possible either that Y is within the circle or that Y
is outside the circle; NOT sufficient.
(2) If the length of the line segment OY is 1.5
and the circle has a radius of 2, then the distance
from the center O to point Y is less than the
radius, and point Y must therefore lie within the
circle; SUFFICIENT.
e correct answer is B;
statement 2 alone is sufficient.
37. Is
xy?>
(1)
=+xy2
(2)
=−
x
y
2
1
Algebra First- and second-degree equations
(1) Since 2 has to be added to y in order to
make it equal to x, it can be reasoned that x > y;
SUFFICIENT.
(2) Multiplying both sides of this equation by
2 results in x = 2(y – 1) or x = 2 y – 2. If y were 0,
then x would be – 2, and y would be greater than
x. If y were a negative number like –2, then
x = 2(–2) – 2 = 6, and again y would be greater
than x. However, if y were a positive number such
as 4, then x = 2(4) –2 = 6, and x > y. Since there is
no other information concerning the value of y, it
cannot be determined if x > y; NOT sufficient.
e correct answer is A;
statement 1 alone is sufficient.
38. If Paula drove the distance from her home to her
college at an average speed that was greater than
70kilometers per hour, did it take her less than
3hours to drive this distance?
(1) The distance that Paula drove from her home to
her college was greater than 200 kilometers.
(2) The distance that Paula drove from her home to
her college was less than 205 kilometers.
Arithmetic Distance problem
A distance problem uses the formula distance =
rate × time. To find the time, the formula would
be rearranged as
time distance
rate
=. To solve this
problem, it is necessary to know the rate (given
here as 70 kilometers per hour) and the distance.
(1) If D is the distance Paula drove then
DD
t200 and
70
200
70
2
6
7
so 2
6
7
>>
=>
and
t may or may not be less than 3; NOT sucient.
(2) If D is the distance Paula drove then
DD
t205 and
70
205
70
2
13
14
so 2
13
14
3;<<
=<
<
SUFFICIENT.
e correct answer is B;
statement 2 alone is sufficient.
39. In the xy‐plane, if line k has negative slope and passes
through the point (–5,r), is the x‐intercept of line k
positive?
(1) The slope of line k is –5.
(2) r > 0
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56
Geometry Coordinate geometry
e x‐intercept is the x‐coordinate of the point
in which the line k crosses the x‐axis and would
have the coordinates (x,0).
(1) Knowing the slope of the line does not
help in determining the x‐intercept, since from
point (–5,r) the line k extends in both directions.
Without knowing the value of r, the x‐intercept
could be –5 if r were 0, or it could be other
numbers, both positive and negative, depending
on the value of r; NOT sufficient.
(2) Knowing that r > 0 suggests that the
x‐intercept is not –5; the point (–5,r), where r
is a positive number, does lie in quadrant II. It
could, however, be any point with an x‐coordinate
of –5 in that quadrant and line k could have any
negative slope, and so the line k would vary with
the value of r. erefore, the x‐intercept of line k
cannot be determined; NOT sufficient.
Using (1) and (2) together does not help in
the determination of the x‐intercept, since the
point (–5,r) could have any positive y‐coordinate
and thus line k could cross the x‐axis at many
dierent places.
e correct answer is E;
both statements together are still not sufficient.
40. If $5,000 invested for one year at p percent simple
annual interest yields $500, what amount must be
invested at k percent simple annual interest for one
year to yield the same number of dollars?
(1) k = 0.8p
(2) k = 8
Arithmetic Interest problem
With simple annual interest, the formula to use is
interest = principal × rate × time. It is given
that
p
$500
$5,000
100 1=×
× (year), so
p = 10 percent interest.
(1) If p is 10 percent, then k = 0.8p is 0.08.
Using the same formula, the time is again 1 year;
the interest is the same amount; and the rate is
0.08, or 8 percent. us, $500 = principal × 0.08 × 1,
or principal $6,250; SUFFICIENT.
(2) If k = 8, then the rate is 8 percent, and
the same formula and procedure as above are
employed again; SUFFICIENT.
e correct answer is D;
each statement alone is sufficient.
41. If
xy
z
x0, is
0?
+><
(1) x < y
(2) z < 0
Algebra Inequalities
If
xy
z
0
+
>, then either one of two cases holds
true. Either
xy()+
> 0 and z > 0, or
xy()+
< 0
and z < 0. In other words, in order for the term to
be greater than zero, it must be true that either 1)
both the numerator and denominator are greater
than 0 or 2) both the numerator and denominator
are less than 0.
(1) Regardless of whether
xy()+
is positive or
negative, the positive or negative value of z must
be in agreement with the sign of
xy()+
in order
for
xy
z0.
+
> However, there is no information
about z here; NOT sufficient.
(2) If z < 0, then
xy()+
must be less than 0.
However, this statement gives no information
about
xy()+
; NOT sufficient.
is can be solved using (1) and (2) together.
From (2), it is known that z < 0, and, going back
to the original analysis, for the term to be greater
than zero,
xy()+
must also be less than 0.
If x + y < 0 then x < –y. But x < y from (1) so
xx yy
x
x
20
0.
+<−+
<
<
e correct answer is C;
both statements together are sufficient.
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57
3.5 Diagnostic Test Quantitative Answer Explanations
42. Does the integer k have at least three different positive
prime factors?
(1)
k
15
is an integer.
(2)
k
10
is an integer.
Arithmetic Properties of numbers
(1) e prime factors of 15 are 3 and 5. So in
this case, k has at least 2 dierent positive prime
factors, but it is unknown if there are more
positive prime factors; NOT sufficient.
(2) e prime factors of 10 are 2 and 5, showing
that k has at least these 2 dierent positive prime
factors, but k might or might not have more;
NOT sufficient.
Taking (1) and (2) together, since k is divisible
by both 10 and 15, it must be divisible by their
dierent positive prime factors of 2, 3, and 5.
us k has at least 3 dierent positive prime
factors.
e correct answer is C;
both statements together are sufficient.
43. In City X last April, was the average (arithmetic mean)
daily high temperature greater than the median daily
high temperature?
(1) In City X last April, the sum of the 30 daily high
temperatures was 2,160°.
(2) In City X last April, 60 percent of the daily high
temperatures were less than the average daily
high temperature.
Arithmetic Statistics
e formula for calculating the arithmetic mean,
or the average, is as follows:
v
v
Average
sumofvalues
=
(1) ese data will produce an average of
2160
30
72
=°
for last April in City X. However,
there is no information regarding the median for
comparison; NOT sufficient.
(2) e median is the middle temperature of
the data. As such, 50 percent of the daily high
temperatures will be at or above the median, and
50 percent will be at or below the median. If
60percent of the daily high temperatures were
less than the average daily high temperature, then
the average of the daily highs must be greater
than the median; SUFFICIENT.
e correct answer is B;
statement 2 alone is sufficient.
44. If m and n are positive integers, is
()
m
n
an integer?
(1)
()
m is an integer.
(2)
()
n is an integer.
Arithmetic Properties of numbers
(1) If
m
()
is an integer and n is a positive
integer, then m
n
()
is an integer because an
integer raised to a positive integer is an integer;
SUFFICIENT.
(2) e information that
n
()
is an integer
is not helpful in answering the question. For
example, if m = 2 and n = 9,
93
=, which is
an integer, but
2162
9
()()
=, which is not
an integer. But if m = 4 and n = 9, then
93=
,
which is an integer, and
42512
99
()
== is an
integer; NOT sucient.
e correct answer is A;
statement 1 alone is sufficient.
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45. Of the 66 people in a certain auditorium, at most 6
people have birthdays in any one given month. Does at
least one person in the auditorium have a birthday in
January?
(1) More of the people in the auditorium have
birthdays in February than in March.
(2) Five of the people in the auditorium have
birthdays in March.
Algebra Sets and functions
Because it is given that 6 is the greatest number
of individuals who can have birthdays in any
particular month, these 66 people could be evenly
distributed across 11 of the 12 months of the
year. at is to say, it could be possible for the
distribution to be 11 × 6 = 66, and thus any given
month, such as January, would not have a person
with a birthday. Assume that January has no
people with birthdays, and see if this assumption
is disproved.
(1) e information that more people have
February birthdays than March birthdays
indicates that the distribution is not even.
erefore, March is underrepresented and must
thus have fewer than 6 birthdays. Since no month
can have more than 6 people with birthdays, and
every month but January already has as many
people with birthdays as it can have, January
has to have at least 1 person with a birthday;
SUFFICIENT.
(2) Again, March is underrepresented with only
5 birthdays, and none of the other months can
have more than 6 birthdays. erefore, the extra
birthday (from March) must occur in January;
SUFFICIENT.
e correct answer is D;
each statement alone is sufficient.
46. Last year the average (arithmetic mean) salary of the
10 employees of Company X was $42,800. What is
the average salary of the same 10 employees this
year?
(1) For 8 of the 10 employees, this year’s salary is
15 percent greater than last year’s salary.
(2) For 2 of the 10 employees, this year’s salary is
the same as last year’s salary.
Arithmetic Statistics
(1) Since all 10 employees did not receive the
same 15 percent increase, it cannot be assumed
that the mean this year is 15 percent higher than
last year. It remains unknown whether these
8salaries were the top 8 salaries, the bottom
8salaries, or somewhere in‐between. Without
this type of information from last year, the
mean for this year cannot be determined; NOT
sufficient.
(2) If 2 salaries remained the same as last
year, then 8 salaries changed. Without further
information about the changes, the mean for this
year cannot be determined; NOT sufficient.
Even taking (1) and (2) together, it remains
impossible to tell the mean salary for this year
without additional data.
e correct answer is E;
both statements together are still not sufficient.
47. In a certain classroom, there are 80 books, of which
24 are fiction and 23 are written in Spanish. How many
of the fiction books are written in Spanish?
(1) Of the fiction books, there are 6 more that are
not written in Spanish than are written in Spanish.
(2) Of the books written in Spanish, there are 5
more nonfiction books than fiction books.
Algebra Sets and functions
Let x represent the fiction books that are written
in Spanish. A table could be set up like the one
below, filling in the information that is known or
able to be known:
Spanish Non‐Spanish Total
Fiction x24
Nonction 56
Total 23 57 80
(1) If x represents the fiction books written in
Spanish, then x + 6 can now be used to represent
the fiction books that are not written in Spanish.
From the table above, it can be seen then that
x + x + 6 = 24, or 2x = 18. erefore, x, or the
number of fiction books written in Spanish, is 9;
SUFFICIENT.
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59
3.5 Diagnostic Test Quantitative Answer Explanations
(2) If x represents the fiction books written in
Spanish, then x + 5 can now be used to represent
the nonfiction books written in Spanish. From
the table, it can be said that x + x + 5 = 23, or
2x = 18. erefore, x, or the number of fiction
books written in Spanish, is 9; SUFFICIENT.
e correct answer is D;
each statement alone is sufficient.
48. If p is the perimeter of rectangle Q, what is the value of
p?
(1) Each diagonal of rectangle Q has length 10.
(2) The area of rectangle Q is 48.
Geometry Rectangles; Perimeter; Area
e perimeter of a rectangle is equal to 2 times
the rectangle’s length plus 2 times the rectangle’s
width, or p = 2l + 2w. e diagonals of a rectangle
are equal. In a rectangle, because a diagonal forms
a right triangle, the length of a diagonal is equal
to the square root of the length squared plus the
width squared, or
dlw
22
=+
.
(1) If a diagonal = 10, then
lw10 22
=+
, or,
by squaring both sides,
lw100 22
=+
. Without
knowing the value or the relationship between
the other two sides of the right triangle, it is
impossible to solve for l or w, and thus for the
perimeter of the rectangle; NOT sufficient.
(2) If the area of the rectangle is 48, then it can
be stated that lw = 48. However, without further
information, the perimeter cannot be determined.
For example, l could be 6 and w could be 8,
and the perimeter would then be 12 + 16 = 28.
However, it could also be that l is 4 and w is
12, and in that case the perimeter would be
8 + 24 = 32; NOT sufficient.
Using (1) and (2) together, it is possible to solve
this problem. Since from (2) lw = 48, then
wl
48
=. Substituting this into
lw100 22
=+
from (1) the equation can be solved as follows:
l
l
100
48
2
2
=+
substitution
ll100 2,304
24
=+ multiply both sides by l2
ll100 2,304 0
42
−+ =
move all terms to one
side
ll64 36 0
22
()()
−−= factor like a quadratic
ll64,36
22
==
solve for l2
Since l is a length, it must be positive, so l is
either 8 or 6. When lw8,
48
86
===, and when
lw
6,
48
68
===, both of which give the same
perimeter.
e correct answer is C;
both statements together are sufficient.
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Questions 1–5 refer to the passage on page 23.
49. Which of the following best describes the purpose of
the sentence in lines 10–15?
(A) To show that economic signaling theory fails to
explain a finding
(B) To introduce a distinction not accounted for by
economic signaling theory
(C) To account for an exception to a generalization
suggested by Marquardt and McGann
(D) To explain why Marquardt and McGann’s research
was conducted
(E) To offer an explanation for an observation
reported by Marquardt and McGann
Logical structure
Marquardt and McGann found a correlation
between highly advertised products and high‐
quality products. e connection can be explained
by understanding that companies may invest
heavily in such advertising, anticipating that
recurring purchases of high‐quality products will
eventually recover these advertising costs. e
consumers will continue to buy these products
over time because of loyalty to their high quality.
e statement in bold provides this explanation
for the correlation noted by Marquardt and
McGann.
A e sentence does not explain a failure of
the economic signaling theory.
B Economic signaling theory is about
perceptions of quality, but this explanation is
about actual quality and its correlation with
advertising.
C No exception is mentioned in Marquardt
and McGann’s work.
D e sentence does not examine why or how
the research was undertaken.
E Correct. is statement provides an
explanation of why highly advertised
products did indeed rank high on certain
measures of product quality.
e correct answer is E.
50. The primary purpose of the passage is to
(A) present findings that contradict one explanation
for the effects of a particular advertising practice
(B) argue that theoretical explanations about the
effects of a particular advertising practice are of
limited value without empirical evidence
(C) discuss how and why particular advertising
practices may affect consumers’ perceptions
(D) contrast the research methods used in two
different studies of a particular advertising
practice
(E) explain why a finding about consumer responses
to a particular advertising practice was
unexpected
3.6 Verbal Answer Explanations
Reading Comprehension
The following discussion is intended to familiarize you with the most efficient and effective approaches
to the kinds of problems common to reading comprehension. The particular questions in this chapter
are generally representative of the kinds of reading comprehension questions you will encounter on the
GMAT exam. Remember that it is the problem solving strategy that is important, not the specific details
of a particular question.
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3.6 Diagnostic Test Verbal Answer Explanations
Main idea
e primary purpose can be determined only by
evaluating the whole passage. e first paragraph
discusses consumers’ perceptions of quality
based on frequency of advertising. e second
paragraph discusses three studies that show how
consumers base their evaluations of products on
the kinds of advertising they see. erefore, the
purpose of the whole passage is to show how
consumers’ perceptions of products are shaped by
certain advertising practices.
A e passage shows that expensive
advertising works to a certain point, but not
after it; this method examines a continuum,
not a contradiction.
B Most of the passage is devoted to empirical
evidence.
C Correct. e passage shows how the
frequency and the kind of advertising
influence consumers’ perceptions about the
quality of the products advertised.
D e passage reports the findings of four
studies but does not mention research
methods.
E e passage does not indicate that any of
the findings were unexpected.
e correct answer is C.
51. Kirmani’s research, as described in the passage,
suggests which of the following regarding consumers’
expectations about the quality of advertised products?
(A) Those expectations are likely to be highest if a
manufacturer runs both black‐and‐white and color
advertisements for the same product.
(B) Those expectations can be shaped by the
presence of color in an advertisement as well as
by the frequency with which an advertisement
appears.
(C) Those expectations are usually high for
frequently advertised new brands but not for
frequently advertised familiar brands.
(D) Those expectations are likely to be higher for
products whose black‐and‐white advertisements
are often repeated than for those whose color
advertisements are less often repeated.
(E) Those expectations are less definitively shaped
by the manufacturer’s advertisements than by
information that consumers gather from other
sources.
Inference
e question’s use of the word suggests means that
the answer depends on making an inference. is
research is discussed in the second paragraph.
Kirmani found that too much advertising
tended to make the consumers believe that
manufacturers were desperate. e use of color
was also found to aect consumers’ perceptions of
brand quality. Realizing that color advertising is
more expensive than black‐and‐white, consumers
react more quickly to what they perceive to be its
overuse than they do to a repetition of black‐and‐
white advertisements.
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A is situation is not discussed in the
research, at least as it is reported in this
passage.
B Correct. It can be inferred that consumers’
perceptions of product quality are influenced
by the use of color in an advertisement and
by the frequency of the advertisement’s
appearance.
C e research does not make a distinction
between new and familiar brands.
D e research indicates only that consumers
can tolerate black‐and‐white advertisements
for a longer time than color advertisements
before dismissing them as excessive.
E ere is no discussion of what consumers
learn from other sources.
e correct answer is B.
52. Kirmani’s third study, as described in the passage,
suggests which of the following conclusions about a
black‐and‐white advertisement?
(A) It can be repeated more frequently than a
comparable color advertisement could before
consumers begin to suspect low manufacturer
confidence in the quality of the advertised
product.
(B) It will have the greatest impact on consumers’
perceptions of the quality of the advertised
product if it appears during periods when a color
version of the same advertisement is also being
used.
(C) It will attract more attention from readers of the
print publication in which it appears if it is used
only a few times.
(D) It may be perceived by some consumers as
more expensive than a comparable color
advertisement.
(E) It is likely to be perceived by consumers as
a sign of higher manufacturer confidence in
the quality of the advertised product than a
comparable color advertisement would be.
Inference
Kirmani’s third study is discussed in the final
two sentences. Consumers suspect expensive
advertising results from a manufacturer’s lack
of confidence in the quality of the product.
Consumers reach the point at which they
find advertising excessive more quickly with
color advertising than with black‐and‐white
advertising because they understand that the
addition of color increases advertising expenses. It
is reasonable to infer that the reverse is also true
and thus that consumers will tolerate lengthier
repetitions of black‐and‐white advertising
without becoming suspicious of product quality.
A Correct. Consumers nd color advertising
excessive more quickly and thus can
be expected to nd black‐and‐white
advertising excessive less quickly.
B e study does not discuss concurrent
appearances of color and black‐and‐white
advertisements for the same product.
C e sole conclusion about frequency is that
consumers can tolerate a greater frequency
of black‐and‐white advertisements than
color advertisements.
D It is stated that consumers understand that
color advertisements are more expensive.
E e research certainly does not report this
nding.
e correct answer is A.
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63
3.6 Diagnostic Test Verbal Answer Explanations
53. The passage suggests that Kirmani would be most
likely to agree with which of the following statements
about consumers’ perceptions of the relationship
between the frequency with which a product is
advertised and the product’s quality?
(A) Consumers’ perceptions about the frequency
with which an advertisement appears are their
primary consideration when evaluating an
advertisement’s claims about product quality.
(B) Because most consumers do not notice the
frequency of advertisement, it has little impact
on most consumers’ expectations regarding
product quality.
(C) Consumers perceive frequency of advertisement
as a signal about product quality only when the
advertisement is for a product that is newly on
the market.
(D) The frequency of advertisement is not always
perceived by consumers to indicate that
manufacturers are highly confident about their
products’ quality.
(E) Consumers who try a new product that has been
frequently advertised are likely to perceive the
advertisement’s frequency as having been an
accurate indicator of the product’s quality.
Inference
e first sentence of the second paragraph
provides the answer to this question: at some level
of spending the manufacturer’s advertising eort
may be perceived as unreasonably high, implying low
manufacturer confidence in product quality. us, it
is logical to assume that if a product is advertised
too frequently, consumers may believe that the
manufacturer is spending excessive amounts on
advertising because that manufacturer is not
confident of the product’s quality.
A Kirmani’s research, as reported here, does
not support this claim.
B Kirmani’s research examines how consumers
respond to the frequency of advertising; the
research does not indicate that consumers
do not notice frequency.
C e research does not distinguish between
new and familiar products.
D Correct. Excessive advertising may lead
consumers to believe that the manufacturer
lacks confidence in the quality of the
product.
E Kirmani’s research does not specifically
address new products.
e correct answer is D.
Questions 6–11 refer to the passage on
page 25.
54. The main purpose of the passage is to
(A) propose an experiment
(B) analyze a function
(C) refute an argument
(D) explain a contradiction
(E) simulate a process
Main idea
Determining the main purpose comes from
considering the passage as a whole. e first
paragraph begins by noting that the idea of the
brain as an information processor is generally
accepted by neuroscientists. e author then
presents Searle as an enemy of this position and
explains Searle’s belief that human thought is
more than information processing. e second
paragraph questions Searle’s position, and the
third asserts that the brain is an information
processor, refuting Searle’s argument.
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A e author uses the idea of a mechanical
simulation of a stomach as a metaphor for a
computer’s simulation of thought; this is not
a proposal for an experiment.
B e author analyzes Searle’s position, but no
function is analyzed.
C Correct. e author explains Searle’s
argument in order to refute it.
D e author points out a weakness in Searle’s
thinking, but not a contradiction.
E e simulation of a process is included as
a metaphor, but it is not essential to the
passage.
e correct answer is C.
55. Which of the following is most consistent with Searle’s
reasoning as presented in the passage?
(A) Meaning and content cannot be reduced to
algorithms.
(B) The process of digestion can be simulated
mechanically, but not on a computer.
(C) Simulated thoughts and real thoughts are
essentially similar because they are composed
primarily of information.
(D) A computer can use “causal powers” similar
to those of the human brain when processing
information.
(E) Computer simulations of the world can achieve
the complexity of the brain’s representations of
the world.
Evaluation
Searle’s position is stated in the first paragraph:
because computers merely follow algorithms, they
cannot deal with important aspects of human thought
such as meaning and content. us, Searle believes
that meaning and content cannot be reduced to
algorithms.
A Correct. Searle believes that meaning and
content cannot be reduced to algorithms.
B e author argues for the mechanical
simulation, but oers no evidence that
Searle would agree.
C is statement reflects the author’s position,
but it is the opposite of Searle’s.
D Searle asserts that only people, not
computers, have the causal powers of the
brain.
E e passage does not discuss computer
simulations of the world.
e correct answer is A.
56. The author of the passage would be most likely to
agree with which of the following statements about the
simulation of organ functions?
(A) An artificial device that achieves the functions of
the stomach could be considered a valid model
of the stomach.
(B) Computer simulations of the brain are best
used to crack the brain’s codes of meaning and
content.
(C) Computer simulations of the brain challenge
ideas that are fundamental to psychology and
neuroscience.
(D) Because the brain and the stomach both act
as processors, they can best be simulated by
mechanical devices.
(E) The computer’s limitations in simulating digestion
suggest equal limitations in computer‐simulated
thinking.
Application
To answer this question, think about how
the author would respond to each statement.
Anticipating the author’s response depends on
understanding the author’s point of view. In this
passage, the author is arguing against Searle’s
view of the brain and in favor of the brain as
information processor. e author believes that
the computer can be a model of the brain and
uses the example of the mechanical stomach to
support his position on simulations.
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3.6 Diagnostic Test Verbal Answer Explanations
A Correct. e first two sentences of the third
paragraph imply that a mechanical device is
a valid model.
B e author believes a computer can simulate
the brain but does not comment on how
these simulations should be used. ere is
no way to predict the author’s reaction to
this statement.
C e author would reject this statement since
neuroscience and psychology do in fact see
the brain as an information processor.
D e author agrees that both the brain and
the stomach act as processors; believes that
the computer, a nonmechanical device,
can simulate the brain; and oers a way
that a mechanical device could simulate
the stomach. e author does not suggest
that mechanical devices are the best way to
simulate both their processes.
E is statement reflects Searle’s viewpoint,
which the author rejects.
e correct answer is A.
57. It can be inferred that the author of the passage
believes that Searle’s argument is flawed by its
failure to
(A) distinguish between syntactic and semantic
operations
(B) explain adequately how people, unlike
computers, are able to understand meaning
(C) provide concrete examples illustrating its claims
about thinking
(D) understand how computers use algorithms to
process information
(E) decipher the code that is transmitted from
neuron to neuron in the brain
Inference
e author’s attitude toward Searle’s argument is
apparent in the first paragraph, which ends with
the author’s summary of what Searle is saying.
Computers understand structures, Searle argues,
but only people understand meaning. How do
people understand meaning? e author notes
that Searle is not able to answer this question
and is able only to assert that people have causal
powers of the brain.
A e author makes it clear in the rst
paragraph that Searle does distinguish
between the two. In Searle’s view computers
are syntactic, interpreting structure or
arrangement, rather than semantic,
understanding meaning.
B Correct. e rst paragraph ends with the
contrast between people and computers:
People, on the other hand, understand meaning
because they have something Searle obscurely
calls the causal powers of the brain. By calling
Searle’s explanation obscure, the author
implies that Searle has not adequately
claried how people understand meaning.
C Nothing in the passage criticizes Searle for
not providing concrete examples. Indeed, in
the second paragraph, the author anticipates
how Searle would react to one concrete
example, the computer simulation of the
stomach.
D In the rst paragraph, the author says
that Searle argues that computers simply
follow algorithms; whether or not Searle
understands how they use algorithms is
irrelevant.
E Since, as the author suggests in the
rst paragraph, Searle does not believe
information could be a code transmitted
from neuron to neuron, he cannot be
expected to decipher that code.
e correct answer is B.
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58. From the passage, it can be inferred that the author
would agree with Searle on which of the following
points?
(A) Computers operate by following algorithms.
(B) The human brain can never fully understand its
own functions.
(C) The comparison of the brain to a machine is
overly simplistic.
(D) The most accurate models of physical processes
are computer simulations.
(E) Human thought and computer‐simulated thought
involve similar processes of representation.
Inference
An inference requires going beyond the material
explicitly stated in the passage to the author’s
ideas that underlie that material. e author and
Searle take opposite points of view on the brain
as information processor. eir area of agreement
is narrow. However, they do both agree that
computers work by following algorithms.
A Correct. e first paragraph explains that
Searle dismisses computers because they
simply follow algorithms; while the author
disagrees with Searle on virtually every
other point, no disagreement is voiced here.
B e first paragraph shows this to be Searle’s
position, but not the author’s.
C e first paragraph shows this to be Searle’s
position, but not the author’s.
D e second paragraph explains Searle’s
rejection of this position.
E e final paragraph establishes this as the
author’s position, but not Searle’s.
e correct answer is A.
59. Which of the following most accurately represents
Searle’s criticism of the brain‐as‐computer metaphor,
as that criticism is described in the passage?
(A) The metaphor is not experimentally verifiable.
(B) The metaphor does not take into account the
unique powers of the brain.
(C) The metaphor suggests that a brain’s functions
can be simulated as easily as those of a
stomach.
(D) The metaphor suggests that a computer can
simulate the workings of the mind by using the
codes of neural transmission.
(E) The metaphor is unhelpful because both the
brain and the computer process information.
Inference
Searle’s criticism of the brain‐as‐computer
metaphor is discussed in the first paragraph.
Computers are merely machines; only people are
endowed with causal powers of the brain that allow
them to understand meaning and content.
A Searle does not believe in the value of the
metaphor, so its verification is beside the
point.
B Correct. Searle believes that people have
something computers do not, causal powers
of the brain for understanding important
aspects of human thought.
C Comparing the brain to a computer, the
metaphor does not make this suggestion.
D In the second paragraph, the author says, but
even if a computer could simulate the workings
of the mind, making it clear that presently it
cannot; this statement does not reflect why
Searle rejects the metaphor.
E is is not the basis of Searle’s objection
since he does not accept the premise that
the brain is an information processor.
e correct answer is B.
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3.6 Diagnostic Test Verbal Answer Explanations
Questions 12–17 refer to the passage on
page 27.
60. The primary purpose of the passage is to
(A) explain why women reformers of the Progressive
Era failed to achieve their goals
(B) discuss the origins of child labor laws in the late
nineteenth and early twentieth centuries
(C) compare the living conditions of working‐class
and middle‐class women in the Progressive Era
(D) discuss an oversight on the part of women
reformers of the Progressive Era
(E) revise a traditional view of the role played by
women reformers in enacting Progressive Era
reforms
Main idea
Understanding the author’s purpose comes only
from reflecting on the passage as a whole. e
beginning of the passage notes the success of
middle‐class women reformers in improving
working conditions for women and children.
e middle discusses the position of working‐
class mothers, who were more concerned with
the economic survival of their families than
with labor reform and consequently tried to
circumvent the laws. e close of the passage
observes that, although middle‐class reformers
were right to point out exploitation of children,
they failed to understand the economic plight of
working‐class families, who needed the income
earned by every possible member. e purpose of
this passage is to show the failure of middle‐class
reformers to understand the economic position of
working‐class families.
A Lines 6–10 emphasize the victories of the
reformers.
B e passage discusses the eects, rather than
the origins, of child labor laws.
C Living conditions of middle‐class and
working‐class women are not compared.
D Correct. As is made clear, especially in
the final sentence of the passage, women
reformers failed to understand the economic
needs of working‐class families.
E A traditional view is not compared with a
newer, revised view of the reformers.
e correct answer is D.
61. The view mentioned in line 17 of the passage refers to
which of the following?
(A) Some working‐class mothers’ resistance to the
enforcement of child labor laws
(B) Reformers’ belief that child labor and industrial
home work should be abolished
(C) Reformers’ opinions about how working‐class
families raised their children
(D) Certain women historians’ observation that there
was a lack of consensus between women of
different classes on the issue of child labor and
industrial home work
(E) Working‐class families’ fears about the adverse
consequences that child labor laws would have
on their ability to earn an adequate living
Inference
To find what this appearance of view refers to, it
is necessary to look back to the beginning of the
sentence. is view, not shared by working‐class
mothers, refers to the reformers’ conviction that
child labor and industrial home work were equally
inhumane practices that should be outlawed.
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A is view must refer back to a point already
stated; resistance to child labor laws is not
discussed until the following sentence.
B Correct. is view refers to the position
of reformers stated earlier in the same
sentence: that child labor and industrial home
work…should be outlawed.
C is view must refer back to a point already
stated; the reformers’ belief that resistance to
child labor laws was due to poor parenting
is discussed later in the passage.
D A number of women historians have said
that working‐class mothers did not always
share the view of middle‐class women
reformers about child labor.
E is view must refer back to a point already
stated; the fears of working‐class families
are examined in the following sentence.
e correct answer is B.
62. The author of the passage mentions the observations
of women historians (lines 15–17) most probably in
order to
(A) provide support for an assertion made in the
preceding sentence (lines 10–12)
(B) raise a question that is answered in the last
sentence of the passage (lines 27–32)
(C) introduce an opinion that challenges a statement
made in the first sentence of the passage
(D) offer an alternative view to the one attributed in
the passage to working‐class mothers
(E) point out a contradiction inherent in the
traditional view of child labor reform as it is
presented in the passage
Evaluation
In lines 10–12, the author asserts that child labor
laws pitted women of dierent classes against one
another. e view of the middle‐class women
reformers is stated, and then, to show that
working‐class mothers did not hold the same
opinion, the author turns to the recent work of
women historians to support this statement.
A Correct. e author uses the recent work of
women historians to support the statement
that women of dierent social classes were
pitted against one another.
B e women historians have recently observed;
the verb observed introduces a statement
rather than a question.
C e reference to women historians has to
do with working‐class mothers; it does
not challenge women’s activism and role in
social reform.
D e passage supports what the women
historians say about working‐class mothers.
E e author does not define or present the
traditional view of child labor reform, nor is
any inherent contradiction pointed out.
e correct answer is A.
63. The passage suggests that which of the following was
a reason for the difference of opinion between working‐
class mothers and women reformers on the issue of
child labor?
(A) Reformers’ belief that industrial home work was
preferable to child labor outside the home
(B) Reformers’ belief that child labor laws should
pertain to working conditions but not to pay
(C) Working‐class mothers’ resentment at reformers’
attempts to interfere with their parenting
(D) Working‐class mothers’ belief that child labor was
an inhumane practice
(E) Working‐class families’ need for every
employable member of their families to earn
money
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69
3.6 Diagnostic Test Verbal Answer Explanations
Inference
e question’s use of the word suggests means
that the answer depends on making an inference.
Lines 12–23 examine the dierent views of
middle‐class reformers and working‐class
mothers on child labor laws. While the reformers
saw child labor as an inhumane practice that
should be outlawed, working class mothers
understood the necessity of pooling the wages of as
many family members as possible and viewed child
labor legislation as a personal economic disaster.
A Lines 12–14 show that reformers regarded
both kinds of work as equally inhumane
practices that should be outlawed.
B Pay is not specifically discussed in the
passage.
C Lines 24–27 indicate that the reformers
believed working‐class resistance to child
labor laws was a sign of poor parenting,
but nothing is said about the working‐class
response to this view.
D Lines 12–17 say that the reformers held this
position, but working class mothers did not
always share this view.
E Correct. Lines 17–23 explain that working‐
class families needed the wages of as many
family members as possible.
e correct answer is E.
64. The author of the passage asserts which of the
following about women reformers who tried to abolish
child labor?
(A) They alienated working‐class mothers by
attempting to enlist them in agitating for
progressive causes.
(B) They underestimated the prevalence of child
labor among the working classes.
(C) They were correct in their conviction that child
labor was deplorable but shortsighted about the
impact of child labor legislation on working‐class
families.
(D) They were aggressive in their attempts to
enforce child labor legislation, but were
unable to prevent working‐class families from
circumventing them.
(E) They were prevented by their nearly total
disenfranchisement from making significant
progress in child labor reform.
Supporting ideas
is question is based on information explicitly
stated in the final sentence of the passage.
Women reformers viewed child labor as a terribly
exploitative practice but they failed to take account of
the economic needs of working‐class families.
A e passage does not say that reformers
tried to enlist working‐class mothers in
progressive causes.
B No evidence is oered to support such a
statement.
C Correct. e final sentence makes clear
that the reformers recognized child labor
as exploitative but did not understand the
economic needs of working‐class families.
D e reformers’ activities involved promoting
legislation; there is no evidence in the
passage that the reformers themselves
attempted to enforce these laws.
E. Lines 6–10 show that the reformers
improved working conditions for
women and children, despite their
disenfranchisement.
e correct answer is C.
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65. According to the passage, one of the most striking
achievements of white middle‐class women reformers
during the Progressive Era was
(A) gaining the right to vote in school elections
(B) mobilizing working‐class women in the fight
against child labor
(C) uniting women of different classes in grassroots
activism
(D) improving the economic conditions of working‐
class families
(E) improving women’s and children’s working
conditions
Supporting ideas
e question’s use of the phrase according to the
passage indicates that the answer can be found
through careful reading of the passage. is
question is based on information explicitly stated
in lines 7–10, which state that white middle‐class
women reformers won a variety of victories, notably
in the improvement of working conditions, especially
for women and children.
A Lines 6–7 show that women already had the
right to vote in school elections.
B Lines 20–24 show that working‐class
families tried to circumvent child labor laws.
C Lines 11–12 say that one product of
grassroots activism, child labor legislation,
pitted women of dierent classes against one
another.
D Lines 31–32 say that the reformers failed to
take account of the economic needs of working‐
class families.
E Correct. e passage states that reformers
improved the working conditions of women
and children.
e correct answer is E.
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3.6 Diagnostic Test Verbal Answer Explanations
Critical Reasoning
The following discussion is intended to familiarize you with the most efficient and effective approaches
to critical reasoning questions. The particular questions in this chapter are generally representative of
the kinds of critical reasoning questions you will encounter on the GMAT exam. Remember that it is the
problem solving strategy that is important, not the specific details of a particular question.
66. Vasquez‐Morrell Assurance specializes in insuring manufacturers. Whenever a policyholder makes a claim, a claims adjuster
determines the amount that Vasquez‐Morrell is obligated to pay. Vasquez‐Morrell is cutting its staff of claims adjusters by
15 percent. To ensure that the company’s ability to handle claims promptly is affected as little as possible by the staff cuts,
consultants recommend that Vasquez‐Morrell lay off those adjusters who now take longest, on average, to complete work
on claims assigned to them.
Which of the following, if true, most seriously calls into question the consultants’ criterion for selecting the staff to be laid off?
(A) If the time that Vasquez‐Morrell takes to settle claims increases signicantly, it could lose business to other insurers.
(B) Supervisors at Vasquez‐Morrell tend to assign the most complex claims to the most capable adjusters.
(C) At Vasquez‐Morrell, no insurance payments are made until a claims adjuster has reached a nal determination on the claim.
(D) There are no positions at Vasquez‐Morrell to which staff currently employed as claims adjusters could be reassigned.
(E) The premiums that Vasquez‐Morrell currently charges are no higher than those charged for similar coverage by
competitors.
Evaluation of a Plan
Situation An insurance company must reduce its sta of claims adjusters. To ensure continuing promptness
in handling claims, consultants advise the company to lay o those adjusters who take the longest
to complete claims.
Reasoning What problem could there be with the criterion? e consultants’ criterion is the time an adjuster takes
to settle a claim. However, some claims are naturally more complicated and require more time. If
it is true that the company now assigns these time‐consuming cases to its most capable adjusters,
then these adjusters would be likely to be the ones who take longest to complete their cases.
Laying o the adjusters who take the longest would thus mean laying o the company’s most
capable sta, which could very well decrease its ability to handle claims promptly.
A e consultants’ advice makes sense if increased time to handle claims causes the company to lose business.
B Correct. is statement properly identifies the problem with the consultants’ criterion.
C is statement merely describes the process of handling a claim; it does not provide any information about
the criterion for layos.
D e consultants make no recommendations for reassigning sta, so indicating that there are no positions
available does not call their advice into question.
E e consultants do not recommend a change in premiums; noting that they are similar to competitors’
premiums does not undermine the plan that the consultants recommend.
e correct answer is B.
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67. Prolonged spells of hot, dry weather at the end of the grape‐growing season typically reduce a vineyard’s yield, because the
grapes stay relatively small. In years with such weather, wine producers can make only a relatively small quantity of wine
from a given area of vineyards. Nonetheless, in regions where wine producers generally grow their own grapes, analysts
typically expect a long, hot, dry spell late in the growing season to result in increased revenues for local wine producers.
Which of the following, if true, does most to justify the analysts’ expectation?
(A) The lower a vineyard’s yield, the less labor is required to harvest the grapes.
(B) Long, hot, dry spells at the beginning of the grape‐growing season are rare, but they can have a devastating effect on
a vineyard’s yield.
(C) Grapes grown for wine production are typically made into wine at or near the vineyard in which they were grown.
(D) When hot, dry spells are followed by heavy rains, the rains frequently destroy grape crops.
(E) Grapes that have matured in hot, dry weather make significantly better wine than ordinary grapes.
Argument Construction
Situation Hot, dry weather at the end of the grape‐growing season reduces yield, so winemakers can
only produce a small quantity of wine. However, analysts expect that this weather will increase
winemakers’ revenues.
Reasoning What additional piece of information explains the analysts’ expectations? e same conditions that
lead to low quantity also lead to something that increases revenues. What could this be? If
these weather conditions lead to higher‐quality wine that will sell for higher prices, the analysts’
expectations for increased revenues are justified.
A Lower labor costs mean less expenditure for the winemakers; this does not explain how revenues would
increase.
B is statement about low yields does not explain an increase in revenues.
C e proximity of production to the vineyard is irrelevant to the question of how hot, dry weather can be
responsible for decreased yield and increased revenues.
D is statement gives another example of weather’s eect on grape crops, but it does not explain how
revenues are increased.
E Correct. is statement properly provides the explanation that the weather conditions will lead to better
wines. With better wines typically commanding higher prices, the winemakers will gain the increased
revenues that the analysts anticipate.
e correct answer is E.
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3.6 Diagnostic Test Verbal Answer Explanations
68. In the past, most children who went sledding in the winter snow in Verland used wooden sleds with runners and steering
bars. Ten years ago, smooth plastic sleds became popular; they go faster than wooden sleds but are harder to steer and
slow. The concern that plastic sleds are more dangerous is clearly borne out by the fact that the number of children injured
while sledding was much higher last winter than it was 10 years ago.
Which of the following, if true in Verland, most seriously undermines the force of the evidence cited?
(A) A few children still use traditional wooden sleds.
(B) Very few children wear any kind of protective gear, such as helmets, while sledding.
(C) Plastic sleds can be used in a much wider variety of snow conditions than wooden sleds can.
(D) Most sledding injuries occur when a sled collides with a tree, a rock, or another sled.
(E) Because the traditional wooden sleds can carry more than one rider, an accident involving a wooden sled can result in
several children being injured.
Argument Evaluation
Situation Ten years ago, wooden sleds began to be replaced by plastic sleds that go faster but are harder
to control. Plastic sleds are more dangerous than wooden sleds because more children suered
injuries last year than they did 10 years ago.
Reasoning What weakens this argument? is argument depends on a comparison of two kinds of sleds. Any
evidence that would either strengthen or weaken the argument must indicate a comparison.
Evidence that applies only to one kind of sled or to both kinds of sleds equally cannot weaken this
argument. Consider the implications of the evidence presented in the answer choices. If plastic
sleds can be used in a wider variety of conditions than wooden sleds can, then plastic sleds can be
used more frequently. It is possible that more frequent use, rather than the sleds themselves, has
led to more accidents.
A e limited use of some wooden sleds does not weaken the argument.
B e absence of protective gear would aect accidents with both kinds of sleds.
C Correct. is statement weakens the argument by providing an alternate explanation for the increased
accidents.
D is statement is true of accidents with both kinds of sleds.
E is explains why wooden sleds may be dangerous but does not weaken the argument that plastic sleds are
even more dangerous.
e correct answer is C.
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69. Metal rings recently excavated from seventh‐century settlements in the western part of Mexico were made using the
same metallurgical techniques as those used by Ecuadorian artisans before and during that period. These techniques are
sufficiently complex to make their independent development in both areas unlikely. Since the people of these two areas
were in cultural contact, archaeologists hypothesize that the metallurgical techniques used to make the rings found in
Mexico were learned by Mexican artisans from Ecuadorian counterparts.
Which of the following would it be most useful to establish in order to evaluate the archaeologists’ hypothesis?
(A) Whether metal objects were traded from Ecuador to western Mexico during the seventh century
(B) Whether travel between western Mexico and Ecuador in the seventh century would have been primarily by land or by
sea
(C) Whether artisans from western Mexico could have learned complex metallurgical techniques from their Ecuadorian
counterparts without actually leaving western Mexico
(D) Whether metal tools were used in the seventh‐century settlements in western Mexico
(E) Whether any of the techniques used in the manufacture of the metal rings found in western Mexico are still practiced
among artisans in Ecuador today
Argument Evaluation
Situation Metal rings excavated from seventh‐century settlements in western Mexico were made with the
same complex techniques used in Ecuador before and during a period when the two cultures
were known to be in contact. Mexican artisans are thought to have learned the techniques from
Ecuadorian artisans.
Reasoning What point could best be applied in evaluating this hypothesis? Consider what specific information
would help to assess the archaeologists’ theory. It is given that the two areas had some cultural
contact. If it were determined that metal objects were traded from one culture to the other, it
could be possible that the metalworking techniques were passed along as well. Such evidence
would be relevant to the hypothesis that Mexican artisans saw the work of their Ecuadorian
counterparts and, from this exchange, learned the techniques to make the metal rings.
A Correct. is statement properly identifies information that would be useful in the evaluation of the
archaeologists’ hypothesis.
B e means of travel is irrelevant to the hypothesis about the source of the techniques.
C e hypothesis is not about where Mexican artisans learned the techniques, but whether they learned
them from the Ecuadorians.
D e existence of metal tools provides no helpful information in establishing whether the Ecuadorians were
the source of the metallurgical techniques.
E e comparison to the present day is irrelevant to the hypothesis.
e correct answer is A.
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3.6 Diagnostic Test Verbal Answer Explanations
70. Following several years of declining advertising sales, the Greenville Times reorganized its advertising sales force. Before
reorganization, the sales force was organized geographically, with some sales representatives concentrating on city‐center
businesses and others concentrating on different outlying regions. The reorganization attempted to increase the sales
representatives’ knowledge of clients’ businesses by having each sales representative deal with only one type of industry or
of retailing. After the reorganization, revenue from advertising sales increased.
In assessing whether the improvement in advertising sales can properly be attributed to the reorganization, it would be most
helpful to find out which of the following?
(A) What proportion of the total revenue of the Greenville Times is generated by advertising sales?
(B) Has the circulation of the Greenville Times increased substantially in the last two years?
(C) Among all the types of industry and retailing that use the Greenville Times as an advertising vehicle, which type
accounts for the largest proportion of the newspaper’s advertising sales?
(D) Do any clients of the sales representatives of the Greenville Times have a standing order with the Times for a fixed
amount of advertising per month?
(E) Among the advertisers in the Greenville Times, are there more types of retail business or more types of industrial
business?
Evaluation of a Plan
Situation In the face of declining advertising sales, a newspaper reorganizes its sales force so that sales
representatives have a better understanding of businesses. Revenue from advertising sales increased
after the reorganization.
Reasoning What additional evidence would help determine the source of the increased revenue? In order to
attribute the increased revenue to the reorganization of the sales force, other possible causes
must be eliminated. Newspaper advertising rates are linked to circulation; when circulation
increases, higher rates can be charged and revenues will increase. An alternate explanation might
be a significant rise in circulation, so it would be particularly helpful to know if circulation had
increased.
A e question concerns only increased revenue from advertising sales; the proportion of advertising revenue
to total revenue is outside the scope of the question.
B Correct. is statement provides another possible explanation for increased revenue of advertising sales,
and so the answer to this question would help to clarify the reason for the increased revenue.
C Knowing how the advertising sales break down by type of business might be useful for other purposes, but
it does not help to show the cause of the increase.
D A fixed amount of advertising would not explain increased revenue, so the answer to this question would
be irrelevant.
E Distinguishing between the types of businesses will not contribute to determining whether the
reorganization was responsible for the increased revenue.
e correct answer is B.
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71. Motorists in a certain country frequently complain that traffic congestion is much worse now than it was 20 years ago.
No real measure of how much traffic congestion there was 20 years ago exists, but the motorists’ complaints are almost
certainly unwarranted. The country’s highway capacity has tripled in the last twenty years, thanks to a vigorous highway
construction program, whereas the number of automobiles registered in the country has increased by only 75 percent.
Which of the following, if true, most seriously weakens the argument?
(A) Most automobile travel is local, and the networks of roads and streets in the country’s settled areas have changed
little over the last twenty years.
(B) Gasoline prices are high, and miles traveled per car per year have not changed much over the last 20 years.
(C) The country’s urban centers have well‐developed public transit systems that carry most of the people who commute
into those centers.
(D) The average age of automobiles registered in the country is lower now than it was 20 years ago.
(E) Radio stations have long been broadcasting regular traffic reports that inform motorists about traffic congestion.
Argument Evaluation
Situation Motorists complain that traffic congestion in their country is much worse than it was twenty years
ago. But these complaints have no basis since the highway capacity in this country has tripled in
the same period, whereas the number of cars registered has risen by only 75 percent.
Reasoning Which point most undermines the argument that the complaints are unwarranted? Consider that the
response to the generalized complaints about congestion discusses only the topic of highway
capacity. What if the congestion that motorists are complaining about is not on highways but on
local roads? Discovering that travel tends to be local in this country and that the local roads have
not been improved in the last twenty years would seriously weaken the argument.
A Correct. is statement properly identifies a weakness in the argument: the response to the broad
complaint addresses a dierent subject, highway capacity, not the issue of traffic congestion encountered by
most motorists.
B If high gas prices actually prevented motorists from driving, and if motorists’ driving habits were the same
as they were twenty years ago, then these points should strengthen the argument that there is no basis for
their complaints.
C e number of commuters who use public transit does not aect the argument that the motorists’
complaints have no basis.
D e age of registered cars is irrelevant to the argument.
E e radio broadcasts attest to the existence of traffic, but not to its increase, so they do not aect the
argument.
e correct answer is A.
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3.6 Diagnostic Test Verbal Answer Explanations
72. The percentage of households with an annual income of more than $40,000 is higher in Merton County than in any other
county. However, the percentage of households with an annual income of $60,000 or more is higher in Sommer County.
If the statements above are true, which of the following must also be true?
(A) The percentage of households with an annual income of $80,000 is higher in Sommer County than in Merton County.
(B) Merton County has the second highest percentage of households with an annual income of $60,000 or more.
(C) Some households in Merton County have an annual income between $40,000 and $60,000.
(D) The number of households with an annual income of more than $40,000 is greater in Merton County than in Sommer
County.
(E) Average annual household income is higher in Sommer County than in Merton County.
Argument Construction
Situation e percentage of households with annual incomes of more than $40,000 is higher in Merton
County than in any other county; the percentage of households with annual incomes of $60,000
or more is higher in Sommer County.
Reasoning On the basis of this information, what point must be true? e given information makes clear that
Merton County has some households that exceed $40,000 in annual income. Sommer County has
a higher percentage of households with annual incomes at or above $60,000. A higher percentage
of the Merton County households must in turn have annual incomes of $60,000 or less. us, the
annual income of some households in Merton County is between $40,000 and $60,000.
A Since it is possible that there are no households with an annual income of $80,000 in Sommer County,
this statement does not follow from the situation.
B It is not possible to make this determination on the basis of the available evidence; Merton County may
have no households at all with an income of more than $60,000.
C Correct. is statement properly identifies a conclusion that can be drawn from the given information: in
order for the percentage of $40,000‐plus incomes to be higher in Merton county than any other county
while Sommer has the highest percentage of $60,000‐plus incomes, there must be some households in
Merton County that bring in between $40,000 and $60,000 annually.
D On the basis of information about the percentages of households, it is not possible to arrive at this
conclusion about the number of households.
E From the given information, it is not possible to determine where the average income is greater. It is
entirely possible that the number of $60,000‐plus incomes in Sommer County is quite small and that the
number of $40,000‐plus incomes in Merton County is substantial.
e correct answer is C.
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73. Tiger beetles are such fast runners that they can capture virtually any nonflying insect. However, when running toward
an insect, a tiger beetle will intermittently stop and then, a moment later, resume its attack. Perhaps the beetles cannot
maintain their pace and must pause for a moment’s rest; but an alternative hypothesis is that while running, tiger beetles are
unable to adequately process the resulting rapidly changing visual information and so quickly go blind and stop.
Which of the following, if discovered in experiments using artificially moved prey insects, would support one of the two
hypotheses and undermine the other?
(A) When a prey insect is moved directly toward a beetle that has been chasing it, the beetle immediately stops and runs
away without its usual intermittent stopping.
(B) In pursuing a swerving insect, a beetle alters its course while running and its pauses become more frequent as the
chase progresses.
(C) In pursuing a moving insect, a beetle usually responds immediately to changes in the insect’s direction, and it pauses
equally frequently whether the chase is up or down an incline.
(D) If, when a beetle pauses, it has not gained on the insect it is pursuing, the beetle generally ends its pursuit.
(E) The faster a beetle pursues an insect fleeing directly away from it, the more frequently the beetle stops.
Argument Evaluation
Situation Two hypotheses are oered to explain the sudden stop that tiger beetles make while pursuing
their prey: (1) they cannot maintain the rapid pace and must rest, and (2) they run too quickly to
process visual information and so temporarily go blind.
Reasoning What point would strengthen one of the two hypotheses and weaken the other? Consider the
information provided in each answer choice, remembering that information that supports one
hypothesis must necessarily detract from the other. Any information that is not about pursuit or
that aects the two hypotheses equally may be dismissed from consideration. If the frequency
of stopping increases when the beetle follows a swerving insect and must constantly change its
course, then the second hypothesis is strengthened; the beetle’s pauses increase as the variety of
visual information that it needs to deal with increases.
A e hypotheses concern ongoing pursuit; since this information is not about the beetle’s continuing pursuit
of prey, it neither strengthens nor weakens either hypothesis.
B Correct. is statement provides information that strengthens the second hypothesis: the swerving pursuit
and the resulting continual course adjustments appear to be forcing the beetle to stop with increasing
frequency to sort out the erratic visual information.
C In this experiment, since neither vision nor tiredness appears to be problematic, the beetle could be
stopping for either reason; this information neither strengthens nor weakens either hypothesis.
D is information is irrelevant since both the hypotheses are about mid‐pursuit behaviors.
E e correlation of frequency of stops with speed aects both hypotheses equally; the pauses could be
equally due to an inability to maintain the pace or due to a need to process the visual information.
e correct answer is B.
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3.6 Diagnostic Test Verbal Answer Explanations
74. Guillemots are birds of Arctic regions. They feed on fish that gather beneath thin sheets of floating ice, and they nest on
nearby land. Guillemots need 80 consecutive snow‐free days in a year to raise their chicks, so until average temperatures
in the Arctic began to rise recently, the guillemots’ range was limited to the southernmost Arctic coast. Therefore, if the
warming continues, the guillemots’ range will probably be enlarged by being extended northward along the coast.
Which of the following, if true, most seriously weakens the argument?
(A) Even if the warming trend continues, there will still be years in which guillemot chicks are killed by an unusually early
snow.
(B) If the Arctic warming continues, guillemots’ current predators are likely to succeed in extending their own range
farther north.
(C) Guillemots nest in coastal areas, where temperatures are generally higher than in inland areas.
(D) If the Arctic warming continues, much of the thin ice in the southern Arctic will disappear.
(E) The fish that guillemots eat are currently preyed on by a wider variety of predators in the southernmost Arctic regions
than they are farther north.
Argument Evaluation
Situation In the southern Arctic, guillemots find their prey beneath thin sheets of ice, nest nearby, and
require 80 snow‐free days to raise their young. A warming trend means that their range may be
enlarged by extending northward along the coast.
Reasoning Which point weakens the argument about the enlargement of the guillemots’ range? How could the
birds move northward and simultaneously not enlarge their range? Consider the assumption
implied by the idea of enlargement. If the guillemots lost their southern habitat, then their
northward move would be a displacement rather than an enlargement. If their source of food was
no longer available to them in the southern Arctic, then they would abandon that area as part of
their range.
A An exceptional year is not an argument against an enlarged range because an unusually early snow could
happen in the southern Arctic as well.
B If their current predators also migrate northward, then the guillemots’ situation has not changed, so this is
not an argument against their enlarged range.
C e argument suggests that they will move not inland, but northward along the coast.
D Correct. is statement properly identifies a factor that weakens the argument: the guillemots’ move
northward would not enlarge their range if they lost their food source, fish found under thin ice, in the
southern Arctic.
E e possibility that they may find prey more easily in the north does not mean that they would abandon
the southern Arctic, and so this point does not weaken the argument.
e correct answer is D.
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75. Some batches of polio vaccine used around 1960 were contaminated with SV40, a virus that in monkeys causes various
cancers. Some researchers now claim that this contamination caused some cases of a certain cancer in humans,
mesothelioma. This claim is not undercut by the fact that a very careful survey made in the 1960s of people who had
received the contaminated vaccine found no elevated incidence of any cancer, since __________.
(A) most cases of mesothelioma are caused by exposure to asbestos
(B) in some countries, there was no contamination of the vaccine
(C) SV40 is widely used in laboratories to produce cancers in animals
(D) mesotheliomas take several decades to develop
(E) mesothelioma was somewhat less common in 1960 than it is now
Argument Construction
Situation Researchers claim that contaminated polio vaccine administered in 1960 caused some cases of
mesothelioma, a type of cancer. eir claim is not undermined by the results of a 1960s survey
showing that those who received the contaminated vaccine had no elevated incidence of cancer.
Reasoning Why did the survey results not challenge the researchers’ claim? e survey did not reveal a higher
incidence of mesothelioma. is question then requires completing a sentence that establishes
cause. What could be the reason that the people surveyed in the 1960s showed no signs of the
disease? If the disease takes decades to develop, then those people surveyed would not yet have
shown any signs of it; less than a decade had passed between their exposure to the vaccine and the
survey.
A e contaminated vaccine is said to have caused some cases, not most; the question remains why the survey
results pose no obstacle to the researchers’ claim.
B e claim is only about contaminated vaccine, not uncontaminated vaccine.
C at the virus can cause cancers in laboratory animals had already been provided as a given; this additional
information is irrelevant to the survey of people who received contaminated vaccine.
D Correct. is statement properly identifies the reason that the survey does not call into question the
researchers’ claim: the people surveyed in the 1960s showed no signs of disease because the cancer takes
decades to develop.
E e frequency of mesothelioma in the general population is not related to the claim that contaminated
vaccine caused the disease in a specific population.
e correct answer is D.
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3.6 Diagnostic Test Verbal Answer Explanations
76. Gortland has long been narrowly self‐sufficient in both grain and meat. However, as per capita income in Gortland has risen
toward the world average, per capita consumption of meat has also risen toward the world average, and it takes several
pounds of grain to produce one pound of meat. Therefore, since per capita income continues to rise, whereas domestic
grain production will not increase, Gortland will soon have to import either grain or meat or both.
Which of the following is an assumption on which the argument depends?
(A) The total acreage devoted to grain production in Gortland will soon decrease.
(B) Importing either grain or meat will not result in a significantly higher percentage of Gortlanders’ incomes being spent
on food than is currently the case.
(C) The per capita consumption of meat in Gortland is increasing at roughly the same rate across all income levels.
(D) The per capita income of meat producers in Gortland is rising faster than the per capita income of grain producers.
(E) People in Gortland who increase their consumption of meat will not radically decrease their consumption of grain.
Argument Construction
Situation A country previously self‐sufficient in grain and meat will soon have to import one or the other or
both. Consumption of meat has risen as per capita income has risen, and it takes several pounds of
grain to produce one pound of meat.
Reasoning What conditions must be true for the conclusion to be true? Meat consumption is rising. What about
grain consumption? A sharp reduction in the amount of grain consumed could compensate for
increased meat consumption, making the conclusion false. If people did radically decrease their
grain consumption, it might not be necessary to import grain or meat or both. Since the argument
concludes that the imports are necessary, it assumes grain consumption will not plunge.
A e argument makes no assumptions about the acreage devoted to grain; it assumes only that the demand
for grain will rise.
B e argument does not discuss the percentage of their income that Gortlanders spend on food, so an
assumption about this topic is not needed.
C e argument involves only meat consumption in general, not its distribution by income level.
D Since the argument does not refer to the incomes of meat producers and grain producers, it cannot depend
on an assumption about them.
E Correct. is statement properly identifies the assumption that there will be no great decrease in grain
consumption.
e correct answer is E.
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77. The Hazelton coal‐processing plant is a major employer in the Hazelton area, but national environmental regulations will
force it to close if it continues to use old, polluting processing methods. However, to update the plant to use newer, cleaner
methods would be so expensive that the plant will close unless it receives the tax break it has requested. In order to prevent
a major increase in local unemployment, the Hazelton government is considering granting the plant’s request.
Which of the following would be most important for the Hazelton government to determine before deciding whether to grant
the plant’s request?
(A) Whether the company that owns the plant would open a new plant in another area if the present plant were closed
(B) Whether the plant would employ far fewer workers when updated than it does now
(C) Whether the level of pollutants presently being emitted by the plant is high enough to constitute a health hazard for
local residents
(D) Whether the majority of the coal processed by the plant is sold outside the Hazelton area
(E) Whether the plant would be able to process more coal when updated than it does now
Evaluation of a Plan
Situation Because of the expenses of mandatory updating, a plant that is a major employer in the local area
will close unless it receives the tax break it has requested from the local government.
Reasoning What point is most critical to the evaluation of the request? Consider the information provided
in the answer choices. e plant is important to the local government primarily because it is a
major employer of local residents. What if updating the plant significantly reduced the number
of employees needed? It is crucial for the local government to determine whether the plant will
continue to employ the same number of people once it has updated.
A e local government is concerned only with the local area, so a new site outside that area is irrelevant.
B Correct. is statement properly identifies a factor that is critical to the plant’s argument and the local
government’s decision.
C Updating is mandatory under national environmental regulations, whether the local residents are aected
by the plant’s pollutants or not.
D At issue is the plant’s role as a major employer; where its product is sold is irrelevant.
E e amount of coal processed by the updated plant is irrelevant to the critical issue of the number of
people employed to process that coal.
e correct answer is B.
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3.6 Diagnostic Test Verbal Answer Explanations
78. A physically active lifestyle has been shown to help increase longevity. In the Wistar region of Bellaria, the average age
at death is considerably higher than in any other part of the country. Wistar is the only mountainous part of Bellaria. A
mountainous terrain makes even such basic activities as walking relatively strenuous; it essentially imposes a physically
active lifestyle on people. Clearly, this circumstance explains the long lives of people in Wistar.
Which of the following, if true, most seriously weakens the argument?
(A) In Bellaria all medical expenses are paid by the government, so that personal income does not affect the quality of
health care a person receives.
(B) The Wistar region is one of Bellaria’s least populated regions.
(C) Many people who live in the Wistar region have moved there in middle age or upon retirement.
(D) The many opportunities for hiking, skiing, and other outdoor activities that Wistar’s mountains offer make it a favorite
destination for vacationing Bellarians.
(E) Per capita spending on recreational activities is no higher in Wistar than it is in other regions of Bellaria.
Argument Evaluation
Situation People in one region of a country live longer than people in other areas. e higher average
age at time of death is attributed to the healthy lifestyle of the people in this region, where the
mountainous terrain demands a physically active life.
Reasoning What point weakens the argument? Consider what assumption underlies the argument that the
physically active lifestyle required of living in Wistar is responsible for its residents’ relative
longevity. e mountainous environment necessitates lifelong levels of rigorous physical activity
that build a more robust population. What if a significant portion of the population has not been
conditioned since childhood to the demands of the terrain? It is assumed here that the healthy
lifestyle imposed by the terrain has shaped residents from birth and accounts for their longer life
span. If many residents only moved there later in life, the argument is weakened.
A e argument is not about the quality of health care throughout the country, but the length of the
residents’ lives in a particular region.
B e rate of population density does not aect the argument.
C Correct. is statement properly identifies a point that weakens the argument.
D e area’s popularity as a vacation destination does not aect the longevity of the local residents.
E e argument establishes that merely living in the region is strenuous; the spending on recreational
activities is irrelevant.
e correct answer is C.
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79. Cheever College offers several online courses via remote computer connection, in addition to traditional classroom‐based
courses. A study of student performance at Cheever found that, overall, the average student grade for online courses
matched that for classroom‐based courses. In this calculation of the average grade, course withdrawals were weighted as
equivalent to a course failure, and the rate of withdrawal was much lower for students enrolled in classroom‐based courses
than for students enrolled in online courses.
If the statements above are true, which of the following must also be true of Cheever College?
(A) Among students who did not withdraw, students enrolled in online courses got higher grades, on average, than
students enrolled in classroom‐based courses.
(B) The number of students enrolled per course at the start of the school term is much higher, on average, for the online
courses than for the classroom‐based courses.
(C) There are no students who take both an online and a classroom‐based course in the same school term.
(D) Among Cheever College students with the best grades, a significant majority take online, rather than classroom‐
based, courses.
(E) Courses offered online tend to deal with subject matter that is less challenging than that of classroom‐based courses.
Argument Construction
Situation A comparison of online and classroom courses showed similar average grades. In determining
average grades, a course withdrawal was weighted as a course failure. e rate of withdrawal was
higher from online than from classroom courses.
Reasoning What conclusion about the courses can be derived from this comparison? Consider the ramifications
of the methodology used to calculate the grade averages for the two types of courses. Because of
course withdrawals, the online courses experienced a higher rate of failure, but the average grade
for these courses still matched the average grade for classroom courses. From this it is logical to
conclude that, for the two averages to match, the students who remained in the online courses
must have had higher initial average grades than those in classroom courses.
A Correct. is statement properly identifies the logical conclusion that the higher percentage of
withdrawals from online classes requires higher grades, on average, to compensate for the higher rate of
failure.
B A number of students cannot be derived from a discussion of average grades and rates of withdrawal.
C is conclusion cannot be determined on the basis of the information provided.
D e information is about average grades; the argument does not provide any basis for a conclusion about
best grades.
E It is impossible to determine the difficulty of subject matter from this information.
e correct answer is A.
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3.6 Diagnostic Test Verbal Answer Explanations
80. For years the beautiful Renaissance buildings in Palitito have been damaged by exhaust from the many tour buses that
come to the city. There has been little parking space, so most buses have idled at the curb during each stop on their tour,
and idling produces as much exhaust as driving. The city has now provided parking that accommodates a third of the tour
buses, so damage to Palitito’s buildings from the buses’ exhaust will diminish significantly.
Which of the following, if true, most strongly supports the argument?
(A) The exhaust from Palitito’s few automobiles is not a significant threat to Palitito’s buildings.
(B) Palitito’s Renaissance buildings are not threatened by pollution other than engine exhaust.
(C) Tour buses typically spend less than one‐quarter of the time they are in Palitito transporting passengers from one site
to another.
(D) More tourists come to Palitito by tour bus than by any other single means of transportation.
(E) Some of the tour buses that are unable to find parking drive around Palitito while their passengers are visiting a site.
Argument Evaluation
Situation Tour buses have damaged Renaissance buildings with their exhaust fumes because lack of
parking has kept the buses idling at curbs. Providing new parking for a third of the buses should
significantly reduce the damage caused by the exhaust.
Reasoning What point strengthens the argument? e argument for reduced damage relies on the reduction of
the vehicles’ exhaust fumes. Any additional evidence regarding the extent to which the vehicular
emissions are likely to be reduced also supports the argument for the benefits of the new parking
spaces. Learning that tour buses spend not just a few minutes but most of their time idling at
the curb strengthens the argument. e new parking spaces will allow a third of the tour buses to
spend 75 percent of their time with their engines o, causing no damage at all.
A If automobile exhaust is not a threat, the argument is not aected.
B is statement does not address the question of whether the new parking will reduce the damage caused
by engine exhaust from the buses.
C Correct. is statement properly cites a factor that supports the argument: since most of the buses’ time
has been spent producing damaging exhaust, the new parking should reduce the damage significantly.
D is statement about tourists’ chosen means of transportation is irrelevant to the issue of what the buses do
while in the city.
E It is given that the new parking will only provide space for a third of the buses, and thus some buses will
continue to idle and some to drive around, continuing to contribute equally to the building damage. is
statement does not strengthen the argument.
e correct answer is C.
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81. During the 1980s and 1990s, the annual number of people who visited the Sordellian Mountains increased continually, and
many new ski resorts were built. Over the same period, however, the number of visitors to ski resorts who were caught in
avalanches decreased, even though there was no reduction in the annual number of avalanches in the Sordellian Mountains.
Which of the following, if true in the Sordellian Mountains during the 1980s and 1990s, most helps to explain the decrease?
(A) Avalanches were most likely to happen when a large new snowfall covered an older layer of snow.
(B) Avalanches destroyed at least some buildings in the Sordellian Mountains in every year.
(C) People planning new ski slopes and other resort facilities used increasingly accurate information about which
locations are likely to be in the path of avalanches.
(D) The average length of stay for people visiting the Sordellian Mountains increased slightly.
(E) Construction of new ski resorts often led to the clearing of wooded areas that had helped prevent avalanches.
Argument Construction
Situation Over a certain period, new ski resorts accommodated an increasing number of visitors at the same
time that fewer visitors were caught in avalanches. Yet there were no fewer avalanches than usual
during this period.
Reasoning What explains the apparent contradiction of increased visitors but fewer visitors caught in avalanches?
More resort visitors would imply more avalanche‐related accidents, but the average has shifted so
that fewer visitors are being caught in the avalanches. It must be that fewer visitors are exposed
to this danger; consider the answer choices to identify a logical reason for this improvement in
their exposure. If the likely paths of avalanches had become better understood, that information
would have been applied to identify safer locations for new ski slopes and ski resorts. e facilities
would thus have been built well out of the way of avalanches, resulting in fewer visitors trapped in
avalanches.
A is likelihood would remain true from year to year; it does not explain the decrease.
B is point does not explain why fewer visitors were caught in these avalanches.
C Correct. is statement properly identifies a factor that explains the decreased number of accidents.
D e greater length of stay would seem to expose visitors to greater danger.
E is information points to an expected increase, rather than decrease, in visitors who might be caught by
avalanches.
e correct answer is C.
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3.6 Diagnostic Test Verbal Answer Explanations
82. A year ago, Dietz Foods launched a yearlong advertising campaign for its canned tuna. Last year Dietz sold 12 million cans
of tuna compared to the 10 million sold during the previous year, an increase directly attributable to new customers brought
in by the campaign. Profits from the additional sales, however, were substantially less than the cost of the advertising
campaign. Clearly, therefore, the campaign did nothing to further Dietz’s economic interests.
Which of the following, if true, most seriously weakens the argument?
(A) Sales of canned tuna account for a relatively small percentage of Dietz Foods’ profits.
(B) Most of the people who bought Dietz’s canned tuna for the first time as a result of the campaign were already loyal
customers of other Dietz products.
(C) A less expensive advertising campaign would have brought in significantly fewer new customers for Dietz’s canned
tuna than did the campaign Dietz Foods launched last year.
(D) Dietz made money on sales of canned tuna last year.
(E) In each of the past five years, there was a steep, industry‐wide decline in sales of canned tuna.
Argument Evaluation
Situation An advertising campaign was responsible for increased sales of canned tuna. Since the profits from
the increased sales were less than the costs of the campaign, the campaign did not contribute to
the company’s economic interests.
Reasoning Which point weakens the argument? Consider the basis of the argument: if profits are lower
than costs, the campaign made no contribution to the company’s financial well‐being. In what
case might this be untrue? What if the advertising campaign reversed an industry‐wide trend
of declining sales? If Dietz experienced increasing sales, while other companies experienced
decreased sales, then the campaign did contribute to the economic interests of the company, and
the argument is considerably weakened.
A e issue is not the percentage of profits that canned tuna contributes, but the success of the advertising
campaign.
B If the customers bought the tuna because of the campaign, it is irrelevant to the argument that they also
bought other Dietz products.
C is information neither strengthens nor weakens the argument.
D e argument is not about profits only, but about whether the advertising campaign contributed to the
economic interests of the company.
E Correct. is statement properly identifies a factor that weakens the argument: the campaign secured the
benefits of increased sales at a time when the entire industry was experiencing a decline in sales.
e correct answer is E.
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83. Unlike the buildings in Mesopotamian cities, which
were arranged haphazardly, the same basic plan was
followed for all cities of the Indus Valley: with houses
laid out on a north‐south, east‐west grid, and houses
and walls were built of standard‐size bricks.
(A) the buildings in Mesopotamian cities, which were
arranged haphazardly, the same basic plan was
followed for all cities of the Indus Valley: with
houses
(B) the buildings in Mesopotamian cities, which were
haphazard in arrangement, the same basic plan
was used in all cities of the Indus Valley: houses
were
(C) the arrangement of buildings in Mesopotamian
cities, which were haphazard, the cities of the
Indus Valley all followed the same basic plan:
houses
(D) Mesopotamian cities, in which buildings were
arranged haphazardly, the cities of the Indus Valley
all followed the same basic plan: houses were
(E) Mesopotamian cities, which had buildings that
were arranged haphazardly, the same basic plan
was used for all cities in the Indus Valley: houses
that were
Comparison-contrast; Modifying clause
e contrast introduced by unlike must be
logical and clear. Contrasting the buildings in
Mesopotamian cities with the same basic plan does
not make sense; Mesopotamian cities should be
contrasted with the cities of the Indus Valley. Also,
it needs to be clear that it was the buildings in the
cities that were arranged haphazardly rather than
the cities. e second half of the sentence needs
houses were laid out to be parallel in structure to
and houses and walls were built.
A Illogically contrasts the buildings in
Mesopotamian cities with the same basic plan;
not clear whether which were arranged
haphazardly modifies cities or buildings; with
houses lacks parallelism and is confusing.
B Illogically contrasts the buildings in
Mesopotamian cities with the same basic plan;
does not clarify what which were haphazard
in arrangement modifies.
C Illogically contrasts the arrangement of
buildings with the cities of the Indus Valley;
not clear whether which were haphazard
modifies buildings or cities; houses not
followed by a verb.
D Correct. In this sentence, Mesopotamian
cities are properly contrasted with the cities
of the Indus Valley; in which buildings were
arranged haphazardly expresses the idea
clearly; and houses is followed by were as
required.
E Illogically contrasts Mesopotamian cities with
the same basic plan; houses that were lacks
parallelism and is confusing.
e correct answer is D.
Sentence Correction
The following discussion is intended to familiarize you with the most efficient and effective approaches
to sentence correction questions. The particular questions in this chapter are generally representative of
the kinds of sentence correction questions you will encounter on the GMAT exam. Remember that it is
the problem solving strategy that is important, not the specific details of a particular question.
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3.6 Diagnostic Test Verbal Answer Explanations
84. New data from United States Forest Service ecologists
show that for every dollar spent on controlled small‐
scale burning, forest thinning, and the training of
fire‐management personnel, it saves seven dollars that
would not be spent on having to extinguish big fires.
(A) that for every dollar spent on controlled small‐
scale burning, forest thinning, and the training
of fire‐management personnel, it saves seven
dollars that would not be spent on having to
extinguish
(B) that for every dollar spent on controlled small‐
scale burning, forest thinning, and the training
of fire‐management personnel, seven dollars
are saved that would have been spent on
extinguishing
(C) that for every dollar spent on controlled small‐
scale burning, forest thinning, and the training of
fire‐management personnel saves seven dollars
on not having to extinguish
(D) for every dollar spent on controlled small‐scale
burning, forest thinning, and the training of
fire‐management personnel, that it saves seven
dollars on not having to extinguish
(E) for every dollar spent on controlled small‐scale
burning, forest thinning, and the training of
fire‐management personnel, that seven dollars
are saved that would not have been spent on
extinguishing
Logical predication; Rhetorical construction
e pronoun it (it saves seven dollars) has no
referent. Making seven dollars the subject of
the clause eliminates this problem, and it also
fulfills a reader’s expectation that after the
phrase beginning for every dollar another specific
amount will be given to balance it. is change
in structure also allows the awkward and wordy
clause that would not be spent on having to
extinguish to be rewritten so that spent balances
saved: seven dollars are saved that would have been
spent on extinguishing, and the unnecessary having
to is omitted.
A It has no referent; not be spent is awkward;
on having to extinguish is wordy.
B Correct. is sentence properly uses seven
dollars as the subject of the clause to balance
every dollar in the introductory phrase; the
phrasing is concise and parallel.
C Saves does not have a subject; construction
is not a complete sentence; not having to
extinguish is wordy and awkward.
D at introduces a subordinate rather than
main clause, making a sentence fragment;
it has no referent; not having to extinguish is
wordy and awkward.
E Introductory that makes a sentence
fragment; that would not have been spent on
extinguishing is awkward and illogical.
e correct answer is B.
85. Like the grassy fields and old pastures that the
upland sandpiper needs for feeding and nesting
when it returns in May after wintering in the Argentine
Pampas, the sandpipers vanishing in the northeastern
United States is a result of residential and industrial
development and of changes in farming practices.
(A) the sandpipers vanishing in the northeastern
United States is a result of residential and
industrial development and of changes in
(B) the bird itself is vanishing in the northeastern
United States as a result of residential and
industrial development and of changes in
(C) that the birds themselves are vanishing in the
northeastern United States is due to residential
and industrial development and changes to
(D) in the northeastern United States, sandpipers’
vanishing due to residential and industrial
development and to changes in
(E) in the northeastern United States, the
sandpipers’ vanishing, a result of residential and
industrial development and changing
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Comparison; Sentence structure
e comparison introduced by like must be
logical and clear; the point of this comparison
is that both the habitat and the bird are
disappearing for similar reasons. e comparison
must use comparable grammatical components;
the bird itself is a noun phrase and matches the
noun phrases grassy fields and old pastures.
A Illogically compares the sandpipers vanishing
to grassy fields and old pastures; omits
apostrophe in sandpipers’ vanishing; wordy.
B Correct. is sentence properly compares
the bird itself to grassy fields and old pastures;
is vanishing as the verb strengthens the
sentence by making the comparison clearer.
C Does not finish the comparison begun with
like but instead substitutes a clause (that the
birds themselves are vanishing).
D Illogically compares the sandpipers’ vanishing
to grassy fields and old pastures; creates a
sentence fragment.
E Illogically compares the sandpipers’ vanishing
to grassy fields and old pastures; creates a
sentence fragment.
e correct answer is B.
86. The results of two recent unrelated studies support the
idea that dolphins may share certain cognitive abilities
with humans and great apes; the studies indicate
dolphins as capable of recognizing themselves in
mirrors—an ability that is often considered a sign of
self‐awareness—and to grasp spontaneously the mood
or intention of humans.
(A) dolphins as capable of recognizing themselves
in mirrors—an ability that is often considered
a sign of self‐awareness—and to grasp
spontaneously
(B) dolphins’ ability to recognize themselves in
mirrors—an ability that is often considered as a
sign of self‐awareness—and of spontaneously
grasping
(C) dolphins to be capable of recognizing
themselves in mirrors—an ability that is often
considered a sign of self‐awareness—and to
grasp spontaneously
(D) that dolphins have the ability of recognizing
themselves in mirrors—an ability that is often
considered as a sign of self‐awareness—and
spontaneously grasping
(E) that dolphins are capable of recognizing
themselves in mirrors—an ability that is often
considered a sign of self‐awareness—and of
spontaneously grasping
Grammatical construction; Parallelism
In the context of this sentence, the studies indicate
must introduce a clause; the clause must begin
with that and have a subject, dolphins, and a verb,
are (the complete verb phrase would be are capable
of ). e two capabilities should be parallel:
capable of recognizing…and of spontaneously
grasping.
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3.6 Diagnostic Test Verbal Answer Explanations
A Context requires a clause, but this
construction is not a clause; capable of
recognizing is not parallel to to grasp
spontaneously.
B Construction is not a clause, and a clause is
required; dolphins’ ability to recognize is not
parallel to of spontaneously grasping.
C A clause is required following the studies
indicate; to be capable of recognizing is not
parallel to to grasp spontaneously.
D Have the ability of is wordy and unidiomatic;
of recognizing and spontaneously grasping are
not parallel.
E Correct. at introduces the subordinate
clause necessary to complete this sentence
properly; of recognizing and of spontaneously
grasping are parallel.
e correct answer is E.
87. According to scholars, the earliest writing was
probably not a direct rendering of speech, but was
more likely to begin as a separate and distinct
symbolic system of communication, and only later
merged with spoken language.
(A) was more likely to begin as
(B) more than likely began as
(C) more than likely beginning from
(D) it was more than likely begun from
(E) it was more likely that it began
Idiom; Verb form
is sentence is a comparison in which probably
not x is balanced by but more than likely y. When
more is used in the comparative form of an
adjective (more difficult) or adverb (more likely),
it is followed by than. e words used to show
the comparison between x and y, but more than
likely, must also introduce the correct verb form,
allowing y to fit grammatically into the rest of the
sentence. e subject of the sentence has three
verbs, all of which should be parallel: the earliest
writing was…began…merged. Was…to begin is not
parallel and results in a construction that is not
grammatically correct.
A In this context, more likely is not a complete
idiomatic expression; was…to begin is not
parallel to was and merged.
B Correct. In this sentence, more than likely
is the correct comparative construction; the
simple past tense began, parallel to was and
merged, fits grammatically into the sentence.
C Subject should be followed by three verbs;
beginning from is not a verb.
D Use of the pronoun it makes this
construction a main clause, in which case
the comma after communication must be
omitted and began must be used to be
parallel to merged; was…begun is not the
correct tense.
E In this awkward, unclear, and wordy
construction, the first it must be followed
by is, not was, because the theory is
current; the second it acts as the subject
of the subordinate clause, and this usage
requires the omission of the comma after
communication.
e correct answer is B.
88. In 1995 Richard Stallman, a well‐known critic of the
patent system, testified in Patent Office hearings that,
to test the system, a colleague of his had managed to
win a patent for one of Kirchhoff’s laws, an observation
about electric current first made in 1845 and now
included in virtually every textbook of elementary
physics.
(A) laws, an observation about electric current first
made in 1845 and
(B) laws, which was an observation about electric
current first made in 1845 and it is
(C) laws, namely, it was an observation about
electric current first made in 1845 and
(D) laws, an observation about electric current first
made in 1845, it is
(E) laws that was an observation about electric
current, first made in 1845, and is
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Logical predication; Parallelism
e function of the entire long phrase
(observation…physics) that follows one of
Kirchho ’s laws is to describe that law. It is a
noun phrase in apposition, which means that it
has the same syntactic relation to all the other
parts of the sentence that the noun phrase one of
Kirchho ’s laws does. Within the long modifying
phrase, parallelism is maintained by balancing an
observation…first made with and now included.
A Correct. In this sentence, the noun phrase
in apposition properly identifies and
explains the law, using parallel structure and
concise expression.
B Which is ambiguous because it could refer to
one or to laws; it is violates the parallelism of
first made and now included.
C It is ambiguous; the introduction of it
was does not allow this construction to fit
grammatically into the sentence.
D e referent of it is unclear; it is creates a
run‐on sentence and violates the parallelism
of first made and now included.
E at appears to refer to laws rather than
one, but the verb is singular; setting o the
phrase first made in 1845 in commas distorts
meaning; is violates parallelism.
e correct answer is A.
89. Excavators at the Indus Valley site of Harappa in
eastern Pakistan say the discovery of inscribed
shards dating to circa 2800–2600 B.C. indicate their
development of a Harappan writing system, the use
of inscribed seals impressed into clay for marking
ownership, and the standardization of weights for trade
or taxation occurred many decades, if not centuries,
earlier than was previously believed.
(A) indicate their development of a Harappan writing
system, the use of
(B) indicate that the development of a Harappan
writing system, using
(C) indicates that their development of a Harappan
writing system, using
(D) indicates the development of a Harappan writing
system, their use of
(E) indicates that the development of a Harappan
writing system, the use of
Agreement; Idiom; Parallelism
In long sentences such as this one, the
relationship between parts of the sentence may
be difficult to see. Here, the main clause of
the sentence is excavators…say and the logical
sequence that follows is the discovery…indicates
that. e subject of this first subordinate clause
is the singular noun discovery, which should be
followed by the singular verb indicates rather than
by the plural indicate, as is done in the original
sentence. eir, used with either development
or use, has no clear or logical referent in any of
the alternatives. e subject of the following
subordinate (that) clause, which has occurred as its
verb, is a series of three phrases, which must be
parallel, especially in a sentence of this length and
complexity: the development of…, the use of…, and
the standardization of….
A Indicate does not agree with discovery; the
pronoun their has no logical referent, and
their development is not parallel to the use
and the standardization.
B Indicate does not agree with discovery; using
is not parallel to the development and the
standardization.
C eir has no logical referent; the series of
three elements should be parallel, but here
all are dierent.
D e pronoun their has no logical referent,
and their use is not parallel to the development
and the standardization; the preferred
sentence structure would have indicates
followed by that when introducing a clause.
E Correct. In this sentence, indicates agrees
with discovery and is followed by that to
introduce a clause; the three parallel phrases
begin with an article (the), a noun, and the
preposition of.
e correct answer is E.
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3.6 Diagnostic Test Verbal Answer Explanations
90. The Supreme Court has ruled that public universities can
collect student activity fees even with students’ objections
to particular activities, so long as the groups they give
money to will be chosen without regard to their views.
(A) with students’ objections to particular activities,
so long as the groups they give money to will be
(B) if they have objections to particular activities and
the groups that are given the money are
(C) if they object to particular activities, but the
groups that the money is given to have to be
(D) from students who object to particular activities,
so long as the groups given money are
(E) though students have an objection to particular
activities, but the groups that are given the
money be
Logical predication; Rhetorical construction
e underlined portion of the sentence fails to
establish a clear relationship among universities,
students, and groups. To which of these three does
they refer? It would appear that the universities must
give the money, but they does not have a referent.
Furthermore, they is followed by their views, and
in this case their must refer to groups. Wordy and
awkward phrasing as well as an unnecessary shift in
verb tense (will be chosen) compound the difficulty of
understanding this sentence in its original form.
A With students’ objections…is awkward and
dense; they does not have a referent; the
future will be is incorrect since the Supreme
Court has already ruled.
B Referent for they is student activity fees,
which cannot possibly have objections…; the
use of and is illogical.
C ey refers to student activity fees rather than
students; but does not have the requisite sense
of with the provision that; have to be is wordy.
D Correct. In this sentence, from students who
object is clear and idiomatic; so long as is used
appropriately; groups given money eliminates
the problem of a pronoun without a
referent; are is the proper tense.
E Have an objection is an unnecessarily wordy
way to say object; the verb be does not
complete the latter part of the sentence.
e correct answer is D.
91. Despite the increasing number of women graduating
from law school and passing bar examinations, the
proportion of judges and partners at major law firms
who are women have not risen to a comparable extent.
(A) the proportion of judges and partners at major
law firms who are women have not risen to a
comparable extent
(B) the proportion of women judges and partners at
major law firms have not risen comparably
(C) the proportion of judges and partners at major law
firms who are women has not risen comparably
(D) yet the proportion of women judges and partners
at major law firms has not risen to a comparable
extent
(E) yet the proportion of judges and partners at major
law firms who are women has not risen comparably
Agreement; Rhetorical construction
When a number of plural nouns appear in
phrases between a singular subject and the verb,
it can be easy to overlook the true subject of the
verb. Here, judges, partners, firms, and women all
occur between the singular subject, proportion,
and the verb, which should also be singular, has
risen. Concise expression is particularly important
in a long construction; to a comparable extent may
be more concisely expressed as comparably.
A Plural verb, have risen, does not agree with
the singular subject, proportion.
B Have risen does not agree with proportion;
here, women applies only to judges, not to
partners at major law firms.
C Correct. In this sentence, has risen agrees
with proportion, and comparably is more
concise than to a comparable extent. e
modifying clause who are women follows
(1)judges and (2) partners at major law firms
as closely as is possible given the content of
the sentence; this positioning has the virtue
of being clear in its meaning.
D e contrast has already been introduced by
despite, so the addition of yet is illogical and
ungrammatical; to a comparable extent is wordy.
E Despite introduces the contrast; adding yet
is illogical and results in an ungrammatical
construction.
e correct answer is C.
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92. Seldom more than 40 feet wide and 12 feet deep,
but it ran 363 miles across the rugged wilderness
of upstate New York, the Erie Canal connected the
Hudson River at Albany to the Great Lakes at Buffalo,
providing the port of New York City with a direct water
link to the heartland of the North American continent.
(A) Seldom more than 40 feet wide and 12 feet
deep, but it ran 363 miles across the rugged
wilderness of upstate New York, the Erie Canal
connected
(B) Seldom more than 40 feet wide or 12 feet
deep but running 363 miles across the rugged
wilderness of upstate New York, the Erie Canal
connected
(C) It was seldom more than 40 feet wide and
12feet deep, and ran 363 miles across the
rugged wilderness of upstate New York, but the
Erie Canal, connecting
(D) The Erie Canal was seldom more than 40 feet
wide or 12 feet deep and it ran 363 miles across
the rugged wilderness of upstate New York,
which connected
(E) The Erie Canal, seldom more than 40 feet wide
and 12 feet deep, but running 363 miles across
the rugged wilderness of upstate New York,
connecting
Logical predication; Grammatical construction
e phrase seldom…deep is the first half of a
modifier that describes the Erie Canal. However,
because a comma incorrectly follows deep, this
phrase appears to be the entire modifier, which
must agree with the noun or pronoun that
immediately follows it. is phrase cannot modify
the conjunction but, and it has no referent; but it
ran is not a logical or grammatical construction
following the modifying phrase. Substituting
running for it ran creates an adjective phrase
parallel to the first adjective phrase (seldom…
deep).To contrast the small size reported in the
first phrase with the great distance reported in the
second, the two phrases may be joined with but;
together they create a single modifier correctly
modifying the Erie Canal. e Erie Canal is then
the subject of the sentence and requires the verb
connected to provide a logical statement.
A But it ran cannot logically or grammatically
follow the modifying phrase.
B Correct. is sentence properly has the
single modifier consisting of two contrasting
parts.
C Neither and nor but acts as a logical
connector; the use of connecting results in a
sentence fragment.
D e paired concepts of width and depth
should be joined by and, not or; this
construction calls for two main clauses to
be separated by a comma after deep; which is
ambiguous.
E e two halves of the modifier should not
be separated by a comma after deep; the
subject is awkwardly and confusingly placed
at a great distance from the predicate;
the use of connecting rather than connected
creates a sentence fragment.
e correct answer is B.
93. In 1923, the Supreme Court declared a minimum wage
for women and children in the District of Columbia
as unconstitutional, and ruling that it was a form of
price‐fixing and, as such, an abridgment of the right of
contract.
(A) the Supreme Court declared a minimum wage
for women and children in the District of
Columbia as unconstitutional, and
(B) the Supreme Court declared as unconstitutional
a minimum wage for women and children in the
District of Columbia, and
(C) the Supreme Court declared unconstitutional a
minimum wage for women and children in the
District of Columbia,
(D) a minimum wage for women and children
in the District of Columbia was declared
unconstitutional by the Supreme Court,
(E) when the Supreme Court declared a minimum
wage for women and children in the District of
Columbia as unconstitutional,
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3.6 Diagnostic Test Verbal Answer Explanations
Idiom; Grammatical construction
is sentence depends on the correct use of
an idiom: the court declares x unconstitutional.
e inverted form should be used here because
of the long phrases involved: the court declares
unconstitutional x. e Supreme Court is the subject
of the sentence; declared is the verb. Ruling…
contract acts as a modifier describing the action
of the main clause; because the modifier is
subordinate to the main clause, the conjunction
and must be omitted. And is used to join two
independent clauses, not a clause and its modifier.
A Declared…as unconstitutional is not the
correct idiom; the use of and creates an
ungrammatical construction.
B Declared as unconstitutional is not the
correct idiom; the use of and creates an
ungrammatical construction.
C Correct. In this sentence, the correct idiom
is used, and the modifier is grammatically
and logically attached to the main clause.
D Passive voice construction is weak and
wordy; its use causes the modifier to be
misplaced and ambiguous.
E Declared…as unconstitutional is not the
correct idiom; when transforms the main
clause into a subordinate clause, resulting in
a sentence fragment.
e correct answer is C.
94. Researchers have found that individuals who have been
blind from birth, and who thus have never seen anyone
gesture, nevertheless make hand motions when
speaking just as frequently and in virtually the same
way as sighted people do, and that they will gesture
even when conversing with another blind person.
(A) who thus have never seen anyone gesture,
nevertheless make hand motions when speaking
just as frequently and in virtually the same way
as sighted people do, and that they will gesture
(B) who thus never saw anyone gesturing,
nevertheless make hand motions when speaking
just as frequent and in virtually the same way as
sighted people did, and that they will gesture
(C) who thus have never seen anyone gesture,
nevertheless made hand motions when speaking
just as frequently and in virtually the same way
as sighted people do, as well as gesturing
(D) thus never having seen anyone gesture,
nevertheless made hand motions when speaking
just as frequent and in virtually the same way as
sighted people did, as well as gesturing
(E) thus never having seen anyone gesture,
nevertheless to make hand motions when
speaking just as frequently and in virtually the
same way as sighted people do, and to gesture
Parallelism; Verb form; Diction
e researchers have found (1) that individuals…
make hand motions…as sighted people do and
(2)that they will gesture…with another blind
person. In the original sentence, the two findings
are reported in two parallel subordinate clauses
introduced by that. e verb tenses are logical and
parallel: who have been blind and who have never
seen indicate a condition that began in the past
and continues in the present; make and do refer
to present actions. e verb make (hand motions)
is correctly modified by the adverb frequently to
show how the action of the verb is carried out.
e emphatic future will gesture is properly used
here with even to emphasize the extreme or the
unexpected.
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A Correct. Although the original sentence is
complicated, the parallelism of its structure
and phrasing allows its meaning to be clear
and its expression eective.
B Verbs saw and did indicate action completed
in the past; the simple past tense is not
appropriate in either case; the adjective
frequent cannot modify the verb; awkward
and muddy.
C Made indicates past action, but the
present tense is logically required; as well
as gesturing violates the parallelism of the
two subordinate (that) clauses; choppy and
unclear.
D Having seen is not parallel to have been;
made and did do not show ongoing action;
frequent incorrectly modifies the verb; as
well as gesturing destroys the parallelism of
the two subordinate (that) clauses; awkward
and unclear.
E Replacing the verb make with the infinitive
to make results in an ungrammatical
construction that fails to complete the
sentence.
e correct answer is A.
95. Like embryonic germ cells, which are cells that
develop early in the formation of the fetus and that
later generate eggs or sperm, embryonic stem cells
have the ability of developing themselves into different
kinds of body tissue.
(A) embryonic stem cells have the ability of
developing themselves into different kinds of
body tissue
(B) embryonic stem cells have the ability to develop
into different kinds of body tissue
(C) in embryonic stem cells there is the ability to
develop into different kinds of body tissue
(D) the ability to develop themselves into different
kinds of body tissue characterizes embryonic
stem cells
(E) the ability of developing into different kinds of
body tissue characterizes embryonic stem cells
Idiom; Grammatical construction
Two constructions create problems in the
original sentence. e first is the unidiomatic
construction have the ability of developing; ability
must be followed by an infinitive, to develop, not
a phrase. e second problematic construction
is to develop themselves into. In this biological
context, the verb develop means to progress from
an earlier to a later stage; it is used intransitively,
which means that it cannot take an object. e
pronoun themselves acts as an object, creating a
construction that is not grammatical or logical.
Omitting the pronoun removes the problem.
A Ability is incorrectly followed by of
developing; a pronoun cannot follow
develop, when it is used, as it is here, in its
intransitive sense.
B Correct. Ability is properly followed by the
infinitive in this sentence, and the pronoun
themselves is omitted.
C is awkward and wordy construction
violates the parallelism of like embryonic
germ cells…embryonic stem cells….
D e two parts of the comparison must be
parallel; like embryonic germ cells must be
followed by embryonic stem cells, not the
ability to develop.
E Ability is followed by the unidiomatic of
developing rather than to develop; the main
clause must begin with embryonic stem cells to
balance and complete like embryonic germ cells.
e correct answer is B.
96. Critics contend that the new missile is a weapon
whose importance is largely symbolic, more a tool for
manipulating people’s perceptions than to fulfill a real
military need.
(A) for manipulating people’s perceptions than to fulfill
(B) for manipulating people’s perceptions than for
fulfilling
(C) to manipulate people’s perceptions rather than
that it fulfills
(D) to manipulate people’s perceptions rather than
fulfilling
(E) to manipulate people’s perceptions than for
fulfilling
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3.6 Diagnostic Test Verbal Answer Explanations
Parallelism
is sentence uses the comparative construction
more x than y where x and y must be parallel.
Here, x is a tool for manipulating people’s
perceptions, and y is to fulfill a real military need. A
tool does not need to be repeated in the second
half of the comparison because it is understood,
but the wording of the two phrases does need to
match. ere are two acceptable solutions: (1) for
manipulating can be followed by for fulfilling or
(2) to manipulate can be followed by to fulfill.
A For manipulating is not parallel to to fulfill.
B Correct. For manipulating and for fulfilling
are parallel in this sentence.
C To manipulate is not parallel to that it fulfills.
D To manipulate is not parallel to fulfilling.
E To manipulate is not parallel to for fulfilling.
e correct answer is B.
97. As an actress and, more importantly, as a teacher
of acting, Stella Adler was one of the most influential
artists in the American theater, who trained several
generations of actors including Marlon Brando and
Robert De Niro.
(A) Stella Adler was one of the most influential
artists in the American theater, who trained
several generations of actors including
(B) Stella Adler, one of the most influential artists
in the American theater, trained several
generations of actors who include
(C) Stella Adler was one of the most influential
artists in the American theater, training several
generations of actors whose ranks included
(D) one of the most influential artists in the American
theater was Stella Adler, who trained several
generations of actors including
(E) one of the most influential artists in the American
theater, Stella Adler, trained several generations
of actors whose ranks included
Logical predication
e original sentence contains a number of
modifiers, but not all of them are correctly
expressed. e clause who trained… describes
Stella Adler, yet a relative clause such as this
one must be placed immediately after the noun
or pronoun it modifies, and this clause follows
theater rather than Adler. Replacing who trained
with training corrects the error because the phrase
training… modifies the whole preceding clause
rather than the single preceding noun. Several
generations of actors including shows the same error
in reverse; including modifies the whole phrase,
but the two actors named are not generations
of actors. e more limiting clause whose ranks
included (referring to actors) is appropriate here.
A Relative (who) clause follows theater rather
than Adler; including refers to generations of
actors, when the reference should be to actors
only.
B is construction, in which the subject is
both preceded and followed by modifiers, is
awkward; the verbs should be consistently in
the past tense, but include is present tense.
C Correct. In this sentence, substituting
training for who trained and whose ranks
included for including eliminates the
modification errors.
D Introductory modifier must be immediately
followed by Stella Adler, not one…; including
refers to generations of actors rather than to
actors only.
E Introductory modifier must be immediately
followed by Stella Adler, not one.
e correct answer is C.
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98. By developing the Secure Digital Music Initiative, the
recording industry associations of North America,
Japan, and Europe hope to create a standardized way
of distributing songs and full‐length recordings on the
Internet that will protect copyright holders and foil the
many audio pirates who copy and distribute digital
music illegally.
(A) of distributing songs and full‐length recordings
on the Internet that will protect copyright holders
and foil the many audio pirates who copy and
distribute
(B) of distributing songs and full‐length recordings
on the Internet and to protect copyright holders
and foiling the many audio pirates copying and
distributing
(C) for distributing songs and full‐length recordings
on the Internet while it protects copyright holders
and foils the many audio pirates who copy and
distribute
(D) to distribute songs and full‐length recordings
on the Internet while they will protect copyright
holders and foil the many audio pirates copying
and distributing
(E) to distribute songs and full‐length recordings on
the Internet and it will protect copyright holders
and foiling the many audio pirates who copy and
distribute
Parallelism
e original sentence depends on the parallelism
of its verbs to make its point clearly and
eectively. A standardized way…will protect and
(will understood) foil; pirates…copy and distribute.
In the first pair of parallel verbs, will does not
need to be repeated because it is understood.
A Correct. e verbs will protect and (will )
foil are parallel in this sentence, as are the
verbs copy and distribute.
B And to protect distorts meaning, suggesting
that protection comes in addition to the
standardized way; foiling is not parallel to to
protect.
C Way for should instead be way of; the
pronoun reference in while it protects is
ambiguous; construction suggests that
protection comes from something other
than the standardized way.
D Pronoun they has no referent; use of while
suggests that protection comes from
something other than the standardized way
of distribution.
E And it will protect distorts meaning,
suggesting that protection comes in addition
to the standardized way; will protect and
foiling are not parallel.
e correct answer is A.
99. Whereas a ramjet generally cannot achieve high
speeds without the initial assistance of a rocket, high
speeds can be attained by scramjets, or supersonic
combustion ramjets, in that they reduce airflow
compression at the entrance of the engine and letting
air pass through at supersonic speeds.
(A) high speeds can be attained by scramjets, or
supersonic combustion ramjets, in that they
reduce
(B) that high speeds can be attained by scramjets,
or supersonic combustion ramjets, is a result of
their reducing
(C) the ability of scramjets, or supersonic
combustion ramjets, to achieve high speeds is
because they reduce
(D) scramjets, or supersonic combustion ramjets,
have the ability of attaining high speeds when
reducing
(E) scramjets, or supersonic combustion ramjets,
can attain high speeds by reducing
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3.6 Diagnostic Test Verbal Answer Explanations
Rhetorical construction
e underlined portion of the original sentence
is wordy and ineective. Transforming it from
passive (high speeds can be attained by scramjets)
to active voice (scramjets can attain high speeds)
eliminates much of the problem. As the subject
of the main clause, scramjets correctly parallels a
ramjet, the subject of the subordinate clause; the
contrast is thus clearly and eectively drawn. In
that they reduce is wordy and awkward; it can be
replaced by the more concise phrase by reducing.
A Passive voice contributes to a wordy,
awkward, and ineective construction; in
that they reduce is also wordy and awkward.
B Passive voice and subordinate (that) clause
constructions are wordy, awkward, and
ineective.
C e ability…is because is not a grammatical
construction; scramjets, not the ability, should
be parallel to a ramjet.
D Have the ability of attaining is wordy; when
does not indicate the cause‐and‐eect
relationship.
E Correct. Scramjets parallels a ramjet for an
eective contrast in this sentence; the active
voice is clear and concise; by reducing shows
how scramjets attain high speeds.
e correct answer is E.
100. It will not be possible to implicate melting sea ice in
the coastal flooding that many global warming models
have projected: just like a glass of water that will not
overflow due to melting ice cubes, so melting sea ice
does not increase oceanic volume.
(A) like a glass of water that will not overflow due to
melting ice cubes,
(B) like melting ice cubes that do not cause a glass
of water to overflow,
(C) a glass of water will not overflow because of
melting ice cubes,
(D) as melting ice cubes that do not cause a glass
of water to overflow,
(E) as melting ice cubes do not cause a glass of
water to overflow,
Diction; Parallelism
e preposition like introduces nouns and noun
phrases; the conjunction as introduces verbs or
clauses, so as is required here. e comparative
construction used here is just as x so y; x and
y must be parallel. e y clause is written in
eective subject‐verb‐object order: melting sea
ice does not increase oceanic volume. e original
wordy, awkward x clause is not parallel. To make
it parallel, melting ice cubes should be the subject
of the clause, do not cause…to overflow the verb
phrase, and a glass of water the object.
A Like is used in place of as; the two elements
of comparison are not parallel.
B Like is used in place of as; that violates
parallelism.
C As or just as is needed to introduce the
clause; the two clauses are not parallel.
D at violates the parallelism of the two
clauses and creates an ungrammatical
construction.
E Correct. is sentence has just as properly
introducing the first clause, and the two
clauses are parallel.
e correct answer is E.
100
4.0 Math Review
101
4.0 Math Review
4.0 Math Review
Although this chapter provides a review of some of the mathematical concepts of arithmetic, algebra,
and geometry, it is not intended to be a textbook. You should use this chapter to familiarize yourself
with the kinds of topics that may be tested in the GMAT® exam. You may wish to consult an
arithmetic, algebra, or geometry book for a more detailed discussion of some of the topics.
Section 4.1, “Arithmetic,” includes the following topics:
1. Properties of Integers
2. Fractions
3. Decimals
4. Real Numbers
5. Ratio and Proportion
6. Percents
7. Powers and Roots of Numbers
8. Descriptive Statistics
9. Sets
10. Counting Methods
11. Discrete Probability
Section 4.2, “Algebra,” does not extend beyond what is usually covered in a rst‐year high school algebra
course. e topics included are as follows:
1. Simplifying Algebraic Expressions
2. Equations
3. Solving Linear Equations with One
Unknown
4. Solving Two Linear Equations with
Two Unknowns
5. Solving Equations by Factoring
6. Solving Quadratic Equations
7. Exponents
8. Inequalities
9. Absolute Value
10. Functions
Section 4.3, “Geometry,” is limited primarily to measurement and intuitive geometry or spatial
visualization. Extensive knowledge of theorems and the ability to construct proofs, skills that are usually
developed in a formal geometry course, are not tested. e topics included in this section are the following:
1. Lines
2. Intersecting Lines and Angles
3. Perpendicular Lines
4. Parallel Lines
5. Polygons (Convex)
6. Triangles
7. Quadrilaterals
8. Circles
9. Rectangular Solids and Cylinders
10. Coordinate Geometry
Section 4.4, “Word Problems,” presents examples of and solutions to the following types of word problems:
1. Rate Problems
2. Work Problems
3. Mixture Problems
4. Interest Problems
5. Discount
6. Pro t
7. Sets
8. Geometry Problems
9. Measurement Problems
10. Data Interpretation
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4.1 Arithmetic
1. Properties of Integers
An integer is any number in the set {. . . −3, −2, −1, 0, 1, 2, 3, . . .}. If x and y are integers and x ≠ 0, then
x is a divisor (factor) of y provided that y = xn for some integer n . In this case, y is also said to be divisible
by x or to be a multiple of x . For example, 7 is a divisor or factor of 28 since 28 = (7)(4), but 8 is not a
divisor of 28 since there is no integer n such that 28 = 8 n .
If x and y are positive integers, there exist unique integers q and r , called the quotient and remainder,
respectively, such that y = xq + r and 0 ≤ r < x . For example, when 28 is divided by 8, the quotient is 3
and the remainder is 4 since 28 = (8)(3) + 4. Note that y is divisible by x if and only if the remainder r
is 0; for example, 32 has a remainder of 0 when divided by 8 because 32 is divisible by 8. Also, note that
when a smaller integer is divided by a larger integer, the quotient is 0 and the remainder is the smaller
integer. For example, 5 divided by 7 has the quotient 0 and the remainder 5 since 5 = (7)(0) + 5.
Any integer that is divisible by 2 is an even integer; the set of even integers is
{. . . −4, −2, 0, 2, 4, 6, 8, . . .}. Integers that are not divisible by 2 are odd integers;
{. . . −3, −1, 1, 3, 5, . . .} is the set of odd integers.
If at least one factor of a product of integers is even, then the product is even; otherwise the product is
odd. If two integers are both even or both odd, then their sum and their di erence are even. Otherwise,
their sum and their di erence are odd.
A prime number is a positive integer that has exactly two di erent positive divisors, 1 and itself. For
example, 2, 3, 5, 7, 11, and 13 are prime numbers, but 15 is not, since 15 has four di erent positive
divisors, 1, 3, 5, and 15. e number 1 is not a prime number since it has only one positive divisor. Every
integer greater than 1 either is prime or can be uniquely expressed as a product of prime factors. For
example, 14 = (2)(7), 81 = (3)(3)(3)(3), and 484 = (2)(2)(11)(11).
e numbers −2, −1, 0, 1, 2, 3, 4, 5 are consecutive integers. Consecutive integers can be represented by
n, n + 1, n + 2, n + 3, . . ., where n is an integer. e numbers 0, 2, 4, 6, 8 are consecutive even integers, and 1,
3, 5, 7, 9 are consecutive odd integers. Consecutive even integers can be represented by 2 n , 2 n + 2, 2 n + 4 , . . .,
and consecutive odd integers can be represented by 2 n + 1, 2 n + 3, 2 n + 5 , . . ., where n is an integer.
Properties of the integer 1. If n is any number, then 1 ⋅ n = n , and for any number n ≠ 0, nn
11⋅=
.
e number 1 can be expressed in many ways; for example, n
n1= for any number n ≠ 0.
Multiplying or dividing an expression by 1, in any form, does not change the value of that expression.
Properties of the integer 0. e integer 0 is neither positive nor negative. If n is any number, then n + 0 = n
and n ⋅ 0 = 0. Division by 0 is not de ned.
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2. Fractions
In a fraction n
dn, is the numerator and d is the denominator. e denominator of a fraction can never be
0, because division by 0 is not de ned.
Two fractions are said to be equivalent if they represent the same number. For example, 8
36 and 14
63 are
equivalent since they both represent the number 2
9. In each case, the fraction is reduced to lowest terms
by dividing both numerator and denominator by their greatest common divisor (gcd). e gcd of 8 and 36
is 4 and the gcd of 14 and 63 is 7.
Addition and subtraction of fractions.
Two fractions with the same denominator can be added or subtracted by performing the required
operation with the numerators, leaving the denominators the same. For example, 3
5
4
5
34
5
7
5
+=+=
and 5
7
2
7
52
7
3
7
−=−=. If two fractions do not have the same denominator, express them as equivalent
fractions with the same denominator. For example, to add 3
5 and 4
7, multiply the numerator and
denominator of the rst fraction by 7 and the numerator and denominator of the second fraction by 5,
obtaining 21
35 and 20
35, respectively; 21
35
20
35
41
35
+=.
For the new denominator, choosing the least common multiple (lcm) of the denominators usually lessens
the work. For 2
3
1
6
+, the lcm of 3 and 6 is 6 (not 3 × 6 = 18), so 2
3
1
6
2
3
2
2
1
6
4
6
1
6
5
6
+=×+=+=.
Multiplication and division of fractions.
To multiply two fractions, simply multiply the two numerators and multiply the two denominators.
For example, 2
3
4
7
24
37
8
21
×=×
×=.
To divide by a fraction, invert the divisor (that is, nd its reciprocal) and multiply. For example,
2
3
4
7
2
3
7
4
14
12
7
6
÷=×= =.
In the problem above, the reciprocal of 4
7 is 7
4. In general, the reciprocal of a fraction n
d is d
n, where n
and d are not zero.
Mixed numbers.
A number that consists of a whole number and a fraction, for example, 72
3, is a mixed number: 72
3
means 72
3
+.
To change a mixed number into a fraction, multiply the whole number by the denominator of the
fraction and add this number to the numerator of the fraction; then put the result over the denominator
of the fraction. For example, 72
3
37 2
3
23
3
()
=×+
=.
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3. Decimals
In the decimal system, the position of the period or decimal point determines the place value of the
digits. For example, the digits in the number 7,654.321 have the following place values:
ousands
Hundreds
Tens
Ones or units
Tenths
Hundredths
ousandths
7 ,654 .321
Some examples of decimals follow.
0.321 3
10
2
100
1
1,000
321
1,000
0.0321 0
10
3
100
2
1,000
1
10, 000
321
10, 000
1.56 1 5
10
6
100
156
100
=+ + =
=+ + + =
=+ + =
Sometimes decimals are expressed as the product of a number with only one digit to the left of the
decimal point and a power of 10. is is called scienti c notation. For example, 231 can be written as
2.31 × 10
2 and 0.0231 can be written as 2.31 × 10
−2 . When a number is expressed in scienti c notation,
the exponent of the 10 indicates the number of places that the decimal point is to be moved in the
number that is to be multiplied by a power of 10 in order to obtain the product. e decimal point is
moved to the right if the exponent is positive and to the left if the exponent is negative. For example,
2.013 × 10
4 is equal to 20,130 and 1.91 × 10
−4 is equal to 0.000191.
Addition and subtraction of decimals.
To add or subtract two decimals, the decimal points of both numbers should be lined up. If one of the
numbers has fewer digits to the right of the decimal point than the other, zeros may be inserted to the
right of the last digit. For example, to add 17.6512 and 653.27, set up the numbers in a column and add:
17.6512
653.2700
670.9212
+
Likewise for 653.27 minus 17.6512:
653.2700
17.6512
635.6188
−
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105
Multiplication of decimals.
To multiply decimals, multiply the numbers as if they were whole numbers and then insert the decimal
point in the product so that the number of digits to the right of the decimal point is equal to the sum of
the numbers of digits to the right of the decimal points in the numbers being multiplied. For example:
2.09 (2 digits to the right)
1.3
627
(l digit to the right)
2090
2.717 (2 1 3 digits to the right)
×
+=
Division of decimals.
To divide a number (the dividend) by a decimal (the divisor), move the decimal point of the divisor to
the right until the divisor is a whole number. en move the decimal point of the dividend the same
number of places to the right, and divide as you would by a whole number. e decimal point in the
quotient will be directly above the decimal point in the new dividend. For example, to divide 698.12
by 12.4:
will be replaced by:
and the division would proceed as follows:
4. Real Numbers
All real numbers correspond to points on the number line and all points on the number line correspond
to real numbers. All real numbers except zero are either positive or negative.
−3
20.2
–1–2–3–4–5–6 5432106
2
4.1 Math Review Arithmetic
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On a number line, numbers corresponding to points to the left of zero are negative and numbers
corresponding to points to the right of zero are positive. For any two numbers on the number line, the
number to the left is less than the number to the right; for example, 43 3
21, and 1 2 2.−<−<− <− < <
To say that the number n is between 1 and 4 on the number line means that n > 1 and n < 4, that is, 1
< n < 4. If n is “between 1 and 4, inclusive,” then 1 ≤ n ≤ 4.
e distance between a number and zero on the number line is called the absolute value of the number.
us 3 and −3 have the same absolute value, 3, since they are both three units from zero. e absolute
value of 3 is denoted |3|. Examples of absolute values of numbers are
|5| |5| 5, 7
2
7
2,and|0| 0.−= = − = =
Note that the absolute value of any nonzero number is positive.
Here are some properties of real numbers that are used frequently. If x , y , and z are real numbers, then
(1) x + y = y + x and xy = yx .
For example, 8 + 3 = 3 + 8 = 11, and (l7)(5) = (5)(l7) = 85.
(2) ( x + y ) + z = x + ( y + z ) and ( xy ) z = x ( yz ).
For example, (7 + 5) + 2 = 7 + (5 + 2) = 7 + (7) = 14, and 53 3 5 33 5 3 15
()() ( )
() ()
()
===.
(3) xy + xz = x ( y + z ).
For example, 718(36) + 718(64) = 718(36 + 64) = 718(l00) = 71,800.
(4) If x and y are both positive, then x + y and xy are positive.
(5) If x and y are both negative, then x + y is negative and xy is positive.
(6) If x is positive and y is negative, then xy is negative.
(7) If xy = 0, then x = 0 or y = 0. For example, 3 y = 0 implies y = 0.
(8) | x + y | ≤ | x | + | y |. For example, if x = 10 and y = 2, then | x + y | = |12| = 12 = | x | + | y |;
and if x = 10 and y = −2, then | x + y | = |8| = 8 < 12 = | x | + | y |.
5. Ratio and Proportion
e ratio of the number a to the number b ( b ≠ 0) is a
b.
A ratio may be expressed or represented in several ways. For example, the ratio of 2 to 3 can be written
as 2 to 3, 2:3, or 2
3. e order of the terms of a ratio is important. For example, the ratio of the number
of months with exactly 30 days to the number with exactly 31 days is 4
7, not 7
4.
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107
A proportion is a statement that two ratios are equal; for example, 2
3 = 8
12 is a proportion. One way to
solve a proportion involving an unknown is to cross multiply, obtaining a new equality. For example, to
solve for n in the proportion 2
3 = n
12
, cross multiply, obtaining 24 = 3 n ; then divide both sides by 3, to
get n = 8.
6. Percents
Percent means per hundred or number out of 100. A percent can be represented as a fraction with a
denominator of 100, or as a decimal. For example:
37% 37
100 0.37.==
To nd a certain percent of a number, multiply the number by the percent expressed as a decimal or
fraction. For example:
20% of 90 0.2 90 18=×=
or
20% of 90 20
100 90 1
590 18=×=×=
.
Percents greater than 100%.
Percents greater than 100% are represented by numbers greater than 1. For example:
300% 300
100 3
250% of 80 2.5 80 200.
==
=×=
Percents less than 1%.
e percent 0.5% means 1
2 of 1 percent. For example, 0.5% of 12 is equal to 0.005 × 12 = 0.06.
Percent change.
Often a problem will ask for the percent increase or decrease from one quantity to another quantity.
For example, “If the price of an item increases from $24 to $30, what is the percent increase in price?”
To nd the percent increase, rst nd the amount of the increase; then divide this increase by the
original amount, and express this quotient as a percent. In the example above, the percent increase
would be found in the following way: the amount of the increase is (30 − 24) = 6. erefore, the
percent increase is 6
24 0.25 25%==.
Likewise, to nd the percent decrease (for example, the price of an item is reduced from $30 to $24),
rst nd the amount of the decrease; then divide this decrease by the original amount, and express this
quotient as a percent. In the example above, the amount of decrease is (30 − 24) = 6.
erefore, the percent decrease is 6
30 0.20 20%==.
Note that the percent increase from 24 to 30 is not the same as the percent decrease from 30 to 24.
4.1 Math Review Arithmetic
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108
In the following example, the increase is greater than 100 percent: If the cost of a certain house in 1983
was 300 percent of its cost in 1970, by what percent did the cost increase?
If n is the cost in 1970, then the percent increase is equal to nn
n
n
n
32
2
−==, or 200%.
7. Powers and Roots of Numbers
When a number k is to be used n times as a factor in a product, it can be expressed as k
n , which means
the nth power of k. For example, 2224
2=×= and 2 2228
3=××= are powers of 2.
Squaring a number that is greater than 1, or raising it to a higher power, results in a larger number;
squaring a number between 0 and 1 results in a smaller number. For example:
39
1
3
1
9
0.1 0.01
(9 3)
1
9
1
3
(0.01 0.1)
2
2
2
()
=
⎛
⎝⎞
⎠=
=
>
<
⎛
⎝⎞
⎠
<
A square root of a number n is a number that, when squared, is equal to n. e square root of a negative
number is not a real number. Every positive number n has two square roots, one positive and the other
negative, but n denotes the positive number whose square is n. For example, 9 denotes 3. e two
square roots of 9 are 93= and −93=− .
Every real number r has exactly one real cube root, which is the number s such that s
3 = r. e real cube
root of r is denoted by r
3. Since 2
3 = 8, 82
3=. Similarly, 82
3−=−, because (−2)
3 = −8.
8. Descriptive Statistics
A list of numbers, or numerical data, can be described by various statistical measures. One of the most
common of these measures is the average, or (arithmetic) mean, which locates a type of “center” for the
data. e average of n numbers is de ned as the sum of the n numbers divided by n. For example, the
average of 6, 4, 7, 10, and 4 is 647104
5
31
56.2
+++ +==.
e median is another type of center for a list of numbers. To calculate the median of n numbers, rst
order the numbers from least to greatest; if n is odd, the median is de ned as the middle number,
whereas if n is even, the median is de ned as the average of the two middle numbers. In the example
above, the numbers, in order, are 4, 4, 6, 7, 10, and the median is 6, the middle number.
For the numbers 4, 6, 6, 8, 9, 12, the median is 68
2
7
+=. Note that the mean of these numbers is 7.5.
e median of a set of data can be less than, equal to, or greater than the mean. Note that for a large set
of data (for example, the salaries of 800 company employees), it is often true that about half of the data
is less than the median and about half of the data is greater than the median; but this is not always the
case, as the following data show.
3, 5, 7, 7, 7, 7, 7, 7, 8, 9, 9, 9, 9, 10, 10
Here the median is 7, but only 2
15 of the data is less than the median.
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109
e mode of a list of numbers is the number that occurs most frequently in the list. For example, the
mode of 1, 3, 6, 4, 3, 5 is 3. A list of numbers may have more than one mode. For example, the list
1, 2, 3, 3, 3, 5, 7, 10, 10, 10, 20 has two modes, 3 and 10.
e degree to which numerical data are spread out or dispersed can be measured in many ways. e
simplest measure of dispersion is the range, which is de ned as the greatest value in the numerical data
minus the least value. For example, the range of 11, 10, 5, 13, 21 is 21 − 5 = 16. Note how the range
depends on only two values in the data.
One of the most common measures of dispersion is the standard deviation. Generally speaking, the
more the data are spread away from the mean, the greater the standard deviation. e standard deviation
of n numbers can be calculated as follows: (1) nd the arithmetic mean, (2) nd the di erences between
the mean and each of the n numbers, (3) square each of the di erences, (4) nd the average of the
squared di erences, and (5) take the nonnegative square root of this average. Shown below is this
calculation for the data 0, 7, 8, 10, 10, which have arithmetic mean 7.
Standard deviation 68
53.7≈
4.1 Math Review Arithmetic
x x − 7(x − 7)
2
0−749
700
811
10 3 9
10 3 9
Total 68
Notice that the standard deviation depends on every data value, although it depends most on values
that are farthest from the mean. is is why a distribution with data grouped closely around the mean
will have a smaller standard deviation than will data spread far from the mean. To illustrate this,
compare the data 6, 6, 6.5, 7.5, 9, which also have mean 7. Note that the numbers in the second set of
data seem to be grouped more closely around the mean of 7 than the numbers in the rst set. is is
re ected in the standard deviation, which is less for the second set (approximately 1.1) than for the rst
set (approximately 3.7).
ere are many ways to display numerical data that show how the data are distributed. One simple
way is with a frequency distribution, which is useful for data that have values occurring with varying
frequencies. For example, the 20 numbers
−4 0 0 −3−2−1−10−1−4
−1−50−2 0 −5−20 0
−1
are displayed on the next page in a frequency distribution by listing each di erent value x and the
frequency f with which x occurs.
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Data Value
x
Frequency
f
−52
−42
−31
−23
−15
07
Total 20
From the frequency distribution, one can readily compute descriptive statistics:
Mean: 52 42 31 23 15 07
20 1.6
() ()
() ( )() ( )() ( )() ( ) ()()
=−+−+−+−+−+ =−
Median: −1 (the average of the 10th and 11th numbers)
Mode: 0 (the number that occurs most frequently)
Range: 0 − (−5) = 5
Standard deviation: 5 1.6 2 4 1.6 2 0 1.6 7
20 1.7
222
()
() ( )() ( )()
−+ +−+ +…+ + ≈
9. Sets
In mathematics a set is a collection of numbers or other objects. e objects are called the elements of the
set. If S is a set having a nite number of elements, then the number of elements is denoted by | S |. Such
a set is often de ned by listing its elements; for example, S = {−5, 0, l} is a set with | S | = 3.
e order in which the elements are listed in a set does not matter; thus {−5, 0, l} = {0, 1, − 5}.
If all the elements of a set S are also elements of a set T, then S is a subset of T; for example,
S = {−5, 0, 1} is a subset of T = {−5, 0, 1, 4, 10}.
For any two sets A and B, the union of A and B is the set of all elements that are in A or in B or in both.
e intersection of A and B is the set of all elements that are both in A and in B. e union is denoted
by A ∪ B and the intersection is denoted by A ∩ B . As an example, if A = {3, 4} and B = {4, 5, 6}, then
A ∪ B = {3, 4, 5, 6} and A ∩ B = {4}. Two sets that have no elements in common are said to be disjoint
or mutually exclusive.
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111
e relationship between sets is often illustrated with a Venn diagram in which sets are represented by
regions in a plane. For two sets S and T that are not disjoint and neither is a subset of the other, the
intersection S ∩ T is represented by the shaded region of the diagram below.
TS
is diagram illustrates a fact about any two nite sets S and T : the number of elements in their
union equals the sum of their individual numbers of elements minus the number of elements in their
intersection (because the latter are counted twice in the sum); more concisely,
ST S T ST||||||||.∪= + −∩
is counting method is called the general addition rule for two sets. As a special case, if S and T are
disjoint, then
ST S T||||||∪= +
since ∩ST||
= 0.
10. Counting Methods
ere are some useful methods for counting objects and sets of objects without actually listing the
elements to be counted. e following principle of multiplication is fundamental to these methods.
If an object is to be chosen from a set of m objects and a second object is to be chosen from a di erent
set of n objects, then there are mn ways of choosing both objects simultaneously.
As an example, suppose the objects are items on a menu. If a meal consists of one entree and one dessert
and there are 5 entrees and 3 desserts on the menu, then there are 5 × 3 = 15 di erent meals that can
be ordered from the menu. As another example, each time a coin is ipped, there are two possible
outcomes, heads and tails. If an experiment consists of 8 consecutive coin ips, then the experiment has
2
8 possible outcomes, where each of these outcomes is a list of heads and tails in some order.
A symbol that is often used with the multiplication principle is the factorial. If n is an integer greater
than 1, then n factorial, denoted by the symbol n!, is de ned as the product of all the integers from 1 to
n. erefore,
2! = (1)(2) = 2,
3! = (1)(2)(3) = 6,
4! = (1)(2)(3)(4) = 24, etc.
Also, by de nition, 0! = 1! = 1.
e factorial is useful for counting the number of ways that a set of objects can be ordered. If a set of
n objects is to be ordered from 1st to n th, then there are n choices for the 1st object, n − 1 choices for
the 2nd object, n − 2 choices for the 3rd object, and so on, until there is only 1 choice for the n th object.
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us, by the multiplication principle, the number of ways of ordering the n objects is
nn n n( 1)( 2) (3)(2)(1) !.−− =
For example, the number of ways of ordering the letters A, B, and C is 3!, or 6:
ABC, ACB, BAC, BCA, CAB, and CBA.
ese orderings are called the permutations of the letters A, B, and C.
A permutation can be thought of as a selection process in which objects are selected one by one in a
certain order. If the order of selection is not relevant and only k objects are to be selected from a larger
set of n objects, a di erent counting method is employed.
Speci cally, consider a set of n objects from which a complete selection of k objects is to be made
without regard to order, where 0 ≤ k ≤ n. en the number of possible complete selections of k objects is
called the number of combinations of n objects taken k at a time and is denoted by n
k
⎛
⎝⎞
⎠.
e value of n
k
⎛
⎝⎞
⎠ is given by n
k
n
kn k
!
!!
()
⎛
⎝⎞
⎠=−.
Note that n
k
⎛
⎝⎞
⎠ is the number of k ‐element subsets of a set with n elements. For example,
if S = { A, B, C, D, E } , then the number of 2‐element subsets of S , or the number of combinations of
5 letters taken 2 at a time, is 5
2
5!
2!3!
120
26 10
()()
⎛
⎝⎞
⎠== =
.
e subsets are {A, B}, {A, C}, {A, D}, {A, E}, {B, C}, {B, D}, {B, E}, {C, D}, {C, E}, and {D, E}. Note
that 5
210 5
3
⎛
⎝⎞
⎠==
⎛
⎝⎞
⎠ because every 2‐element subset chosen from a set of 5 elements corresponds to a
unique 3‐element subset consisting of the elements not chosen.
In general, n
kn
nk
⎛
⎝⎞
⎠=−
⎛
⎝⎞
⎠.
11. Discrete Probability
Many of the ideas discussed in the preceding three topics are important to the study of discrete
probability. Discrete probability is concerned with experiments that have a nite number of outcomes.
Given such an experiment, an event is a particular set of outcomes. For example, rolling a number cube
with faces numbered 1 to 6 (similar to a 6‐sided die) is an experiment with 6 possible outcomes:
1, 2, 3, 4, 5, or 6. One event in this experiment is that the outcome is 4, denoted {4}; another event is
that the outcome is an odd number: {1, 3, 5}.
e probability that an event E occurs, denoted by P (E), is a number between 0 and 1, inclusive.
If E has no outcomes, then E is impossible and P ( E ) = 0; if E is the set of all possible outcomes of the
experiment, then E is certain to occur and P ( E ) = 1. Otherwise, E is possible but uncertain, and
0 < P ( E ) < 1. If F is a subset of E, then P ( F ) ≤ P ( E ). In the example above, if the probability of each of
the 6 outcomes is the same, then the probability of each outcome is 1
6, and the outcomes are said to be
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equally likely. For experiments in which all the individual outcomes are equally likely, the probability of
an event E is
PE EThe number of outcomes in
The total number of possible outcomes .
()
=
In the example, the probability that the outcome is an odd number is
P{1,3,5} |{1, 3, 5}|
6
3
6
1
2.
()
===
Given an experiment with events E and F , the following events are de ned:
“not E ” is the set of outcomes that are not outcomes in E ;
“E or F ” is the set of outcomes in E or F or both, that is, E ∪ F ;
“E and F” is the set of outcomes in both E and F, that is, E ∩ F .
e probability that E does not occur is P (not E ) = l − P ( E ). e probability that “ E or F ” occurs is
P ( E or F ) = P ( E ) + P ( F ) − P ( E and F ), using the general addition rule at the end of section 4.1.9
(“Sets”). For the number cube, if E is the event that the outcome is an odd number, {1, 3, 5}, and F is
the event that the outcome is a prime number, {2, 3, 5}, then PE F P(and) {3,5} 2
6
1
3
()
=== and so
PE F PE PF PE For and 3
6
3
6
2
6
4
6
2
3
() ( )
() ()
=+− =+−==
.
Note that the event “E or F ” is E ∪ F = { 1, 2, 3, 5}, and hence PE F(or)| {1, 2, 3, 5}|
6
4
6
2
3
===.
If the event “E and F ” is impossible (that is, E ∩ F has no outcomes), then E and F are said to be
mutually exclusive events, and P ( E and F ) = 0. en the general addition rule is reduced to
P ( E or F ) = P ( E ) + P ( F ).
is is the special addition rule for the probability of two mutually exclusive events.
Two events A and B are said to be independent if the occurrence of either event does not alter the
probability that the other event occurs. For one roll of the number cube, let A = {2, 4, 6} and let
B = {5, 6}. en the probability that A occurs is
P
AA
()||
6
3
6
1
2
===, while, presuming B occurs, the
probability that A occurs is
AB
B
||
||
|{6}|
|{5,6}|
1
2.
∩==
Similarly, the probability that B occurs is PB B||
6
2
6
1
3
()
===, while, presuming A occurs, the probability
that B occurs is
BA
A
||
||
|{6}|
|{2,4,6}|
1
3.
∩==
us, the occurrence of either event does not a ect the probability that the other event occurs.
erefore, A and B are independent.
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e following multiplication rule holds for any independent events E and F: P ( E and F ) = P ( E ) P ( F ).
For the independent events A and B above, PA B PAPB(and) ()() 1
2
1
3
1
6
==
⎛
⎝⎞
⎠⎛
⎝⎞
⎠=⎛
⎝⎞
⎠.
Note that the event “A and B” is A ∩ B = {6}, and hence
P
ABP(and) {6} 1
6
()
==. It follows from the
general addition rule and the multiplication rule above that if E and F are independent, then
PE F PE PF PEPF( or ) () () ()().=+−
For a nal example of some of these rules, consider an experiment with events A, B, and C for which
P ( A ) = 0.23, P ( B ) = 0.40, and P ( C ) = 0.85. Also, suppose that events A and B are mutually exclusive and
events B and C are independent. en
PA B PA PB A B
PB C PB PC PBPC
or ( ) (since or are mutually exclusive)
0.23 0.40
0.63
( or ) () () ()()(byindependence)
0.40 0.85 (0.40)(0.85)
0.91
()
()
=+
=+
=
=+−
=+−
=
Note that P (A or C) and P (A and C) cannot be determined using the information given. But it can be
determined that A and C are not mutually exclusive since P ( A ) + P ( C ) = 1.08, which is greater than 1,
and therefore cannot equal P(A or C ); from this it follows that P ( A and C ) ≥ 0.08. One can also deduce
that P ( A and C ) ≤ P ( A ) = 0.23, since A ∩ C is a subset of A , and that P ( A or C ) ≥ P ( C ) = 0.85 since C
is a subset of A ∪ C . us, one can conclude that 0.85 ≤ P ( A or C ) ≤ 1 and 0.08 ≤ P ( A and C ) ≤ 0.23.
4.2 Algebra
Algebra is based on the operations of arithmetic and on the concept of an unknown quantity, or
variable. Letters such as x or n are used to represent unknown quantities. For example, suppose Pam
has 5 more pencils than Fred. If F represents the number of pencils that Fred has, then the number of
pencils that Pam has is F + 5. As another example, if Jim’s present salary S is increased by 7%, then his
new salary is 1.07S. A combination of letters and arithmetic operations, such as
Fx
x
5, 3
25
2
+− , and 19 x
2 − 6 x + 3, is called an algebraic expression.
e expression 19 x
2 − 6 x + 3 consists of the terms 19 x
2 , −6 x , and 3, where 19 is the coe cient of x
2 ,
−6 is the coe cient of x
1 , and 3 is a constant term (or coe cient of x
0 = 1 ). Such an expression is called
a second degree (or quadratic) polynomial in x since the highest power of x is 2. e expression F + 5 is a
rst degree (or linear) polynomial in F since the highest power of F is 1. e expression x
x
3
25
2
− is not a
polynomial because it is not a sum of terms that are each powers of x multiplied by coe cients.
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1. Simplifying Algebraic Expressions
Often when working with algebraic expressions, it is necessary to simplify them by factoring or
combining like terms. For example, the expression 6 x + 5 x is equivalent to (6 + 5) x , or 11 x .
In the expression 9 x − 3 y , 3 is a factor common to both terms: 9 x − 3 y = 3(3 x − y ). In the expression
5 x
2 + 6 y , there are no like terms and no common factors.
If there are common factors in the numerator and denominator of an expression, they can be divided
out, provided that they are not equal to zero.
For example, if x ≠ 3, then x
x
3
3
−
− is equal to 1; therefore,
xy y
x
yx
x
y
y
39
3
33
3
31
3
()
()
()
−
−=−
−
=
=
To multiply two algebraic expressions, each term of one expression is multiplied by each term of the
other expression. For example:
x yx xyx yx
xy xx y x
xy x y x
(3 4)(9 ) 3 (9 ) 4(9 )
3(9) 3 4(9)(4)
27 3 36 4
2
() ()()() ()
−+= +−+
=++−+−
=+−−
An algebraic expression can be evaluated by substituting values of the unknowns in the expression. For
example, if x = 3 and y = −2 , then 3 xy − x
2 + y can be evaluated as
3(3)( 2) (3) ( 2) 18 9 2 29
2
− − + − =− − − =−
2. Equations
A major focus of algebra is to solve equations involving algebraic expressions. Some examples of such
equations are
xx
xy
xx x
xx x
x
5 2 9 (a linear equation with one unknown)
3 1 2 (a linear equation with two unknowns)
5 3 2 7 (a quadratic equation with one unknown)
3( 5)
40 (an equation that is factored on one side with 0 on the other)
2
2
()
−=−
+= −
+−=
−+
−=
e solutions of an equation with one or more unknowns are those values that make the equation true,
or “satisfy the equation,” when they are substituted for the unknowns of the equation. An equation
may have no solution or one or more solutions. If two or more equations are to be solved together, the
solutions must satisfy all the equations simultaneously.
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Two equations having the same solution(s) are equivalent equations. For example, the equations
x
x
23
42 6
+=
+=
each have the unique solution x = 1. Note that the second equation is the rst equation multiplied by 2.
Similarly, the equations
xy
xy
36
6212
−=
−=
have the same solutions, although in this case each equation has in nitely many solutions. If any value is
assigned to x , then 3 x − 6 is a corresponding value for y that will satisfy both equations; for example,
x = 2 and y = 0 is a solution to both equations, as is x = 5 and y = 9.
3. Solving Linear Equations with One Unknown
To solve a linear equation with one unknown (that is, to nd the value of the unknown that satis es the
equation), the unknown should be isolated on one side of the equation. is can be done by performing
the same mathematical operations on both sides of the equation. Remember that if the same number
is added to or subtracted from both sides of the equation, this does not change the equality; likewise,
multiplying or dividing both sides by the same nonzero number does not change the equality. For
example, to solve the equation x56
34
−= for x , the variable x can be isolated using the following steps:
x
x
x
5 6 12 (multiplying by 3)
5 18 (adding 6)
18
5(dividing by 5)
−=
=
=
e solution, 18
5, can be checked by substituting it for x in the original equation to determine whether
it satis es that equation:
518
56
3
18 6
3
12
34
⎛
⎝⎞
⎠−
=−==
erefore, x18
5
= is the solution.
4. Solving Two Linear Equations with Two Unknowns
For two linear equations with two unknowns, if the equations are equivalent, then there are in nitely
many solutions to the equations, as illustrated at the end of section 4.2.2 (“Equations”). If the equations
are not equivalent, then they have either one unique solution or no solution. e latter case is illustrated
by the two equations:
xy
xy
3417
68 35
+=
+=
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Note that 3 x + 4 y = 17 implies 6 x + 8 y = 34, which contradicts the second equation. us, no values of x
and y can simultaneously satisfy both equations.
ere are several methods of solving two linear equations with two unknowns. With any method, if
a contradiction is reached, then the equations have no solution; if a trivial equation such as 0 = 0 is
reached, then the equations are equivalent and have in nitely many solutions. Otherwise, a unique
solution can be found.
One way to solve for the two unknowns is to express one of the unknowns in terms of the other using
one of the equations, and then substitute the expression into the remaining equation to obtain an
equation with one unknown. is equation can be solved and the value of the unknown substituted into
either of the original equations to nd the value of the other unknown. For example, the following two
equations can be solved for x and y.
(1) xy32 11+=
(2) xy2−=
In equation (2), x = 2 + y . Substitute 2 + y in equation (1) for x :
yy
yy
y
y
y
3(2 ) 2 11
63 2 11
65 11
55
1
++ =
++=
+=
=
=
If y = 1, then x − 1 = 2 and x = 2 + 1 = 3.
ere is another way to solve for x and y by eliminating one of the unknowns. is can be done by making
the coe cients of one of the unknowns the same (disregarding the sign) in both equations and either
adding the equations or subtracting one equation from the other. For example, to solve the equations
(1) xy65 29+=
(2) xy43 6−=−
by this method, multiply equation (1) by 3 and equation (2) by 5 to get
xy
xy
18 15 87
20 15 30
+=
−=−
Adding the two equations eliminates y , yielding 38 x = 57, or x = 3
2. Finally, substituting 3
2 for x in one
of the equations gives y = 4. ese answers can be checked by substituting both values into both of the
original equations.
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5. Solving Equations by Factoring
Some equations can be solved by factoring. To do this, rst add or subtract expressions to bring all the
expressions to one side of the equation, with 0 on the other side. en try to factor the nonzero side into
a product of expressions. If this is possible, then using property (7) in section 4.1.4 (“Real Numbers”)
each of the factors can be set equal to 0, yielding several simpler equations that possibly can be solved.
e solutions of the simpler equations will be solutions of the factored equation. As an example,
consider the equation x
3 − 2 x
2 + x = −5(x − l)
2 :
xxxx
xx x x
xx x
xx
xx
xx
2510
215 1 0
15 10
510
50or 1 0
5or 1.
32 2
22
22
2
2
()
()
()
()
()()
()
()
−++−=
−++ − =
−+ −=
+−=
+= − =
=− =
For another example, consider xx x
x
35
40.
2
()
()
−+
−= A fraction equals 0 if and only if its numerator
equals 0. us, x ( x − 3)( x
2 + 5) = 0:
x = 0 or x − 3 = 0 or x
2 + 5 = 0
x = 0 or x = 3 or x
2 + 5 = 0.
But x
2 + 5 = 0 has no real solution because x
2 + 5 > 0 for every real number. us, the solutions are 0
and 3.
e solutions of an equation are also called the roots of the equation. ese roots can be checked by
substituting them into the original equation to determine whether they satisfy the equation.
6. Solving Quadratic Equations
e standard form for a quadratic equation is
ax
2 + bx + c = 0,
where a , b , and c are real numbers and a ≠ 0; for example:
xx
xx
x
650
320,and
40
2
2
2
++=
−=
+=
Some quadratic equations can easily be solved by factoring. For example:
(1) xx
xx
xx
xx
650
(5)(1)0
50or 10
5or 1
2++=
++=
+= +=
=− =−
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119
(2) xx
xx
xx
xx
xx
338
3830
(3 1)( 3) 0
310or 30
1
3or 3
2
2
−=
−−=
+−=
+= −=
=− =
A quadratic equation has at most two real roots and may have just one or even no real root. For
example, the equation x
2 − 6 x + 9 = 0 can be expressed as ( x − 3)
2 = 0, or ( x − 3)( x − 3) = 0; thus the
only root is 3. e equation x
2 + 4 = 0 has no real root; since the square of any real number is greater
than or equal to zero, x
2 + 4 must be greater than zero.
An expression of the form a
2 − b
2 can be factored as ( a − b )( a + b ).
For example, the quadratic equation 9 x
2 − 25 = 0 can be solved as follows.
xx
xx
xx
35350
350or350
5
3or 5
3
()()
−+=
−= +=
==−
If a quadratic expression is not easily factored, then its roots can always be found using the quadratic
formula: If ax
2 + bx + c = 0 ( a ≠ 0), then the roots are
xbb ac
axbb ac
a
4
2and 4
2
22
=−+ − =−− −
ese are two distinct real numbers unless b
2 − 4 ac ≤ 0. If b
2 − 4 ac = 0, then these two expressions for
x are equal to −b
a2, and the equation has only one root. If b
2 − 4 ac < 0, then bac4
2− is not a real
number and the equation has no real roots.
7. Exponents
A positive integer exponent of a number or a variable indicates a product, and the positive integer is
the number of times that the number or variable is a factor in the product. For example, x
5 means
(x)(x)(x)(x)(x); that is, x is a factor in the product 5 times.
Some rules about exponents follow.
Let x and y be any positive numbers, and let r and s be any positive integers.
(1) ( x
r )( x
s ) = x
( r + s ) ; for example, (2
2 )(2
3 ) = 2
( 2 + 3 ) = 2
5 = 32.
(2) x
xx
r
s
rs
=
()
−; for example, 4
44464
5
2
52 3
===
−.
(3) ( x
r )( y
r ) = ( xy ) r ; for example, (3
3 )(4
3 ) = 12
3 = 1,728.
(4) x
y
x
y
rr
r
⎛
⎝
⎜⎞
⎠
⎟=; for example, 2
3
2
3
8
27
33
3
⎛
⎝⎞
⎠==.
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(5) ( x
r )
s = x
rs = ( x
s )
r ; for example, ( x
3 )
4 = x 12 = ( x
4 )
3 .
(6) x
− r
=
x
1
r ; for example, 31
3
1
9
2
2
==
−.
(7) x
0 = 1; for example, 6
0 = 1.
(8) xx x x
r
ss
r
rsr
s
11
()
=⎛
⎝
⎜⎞
⎠
⎟==; for example, 8 8 8 8 64 4
2
3
1
3
2
21
32
33
()
=⎛
⎝
⎜⎞
⎠
⎟==== and 993
1
2==.
It can be shown that rules 1 − 6 also apply when r and s are not integers and are not positive, that is,
when r and s are any real numbers.
8. Inequalities
An inequality is a statement that uses one of the following symbols:
≠ not equal to
> greater than
≥ greater than or equal to
< less than
≤ less than or equal to
Some examples of inequalities are 5 x − 3 < 9, 6 x ≥ y, and 1
2 < 3
4. Solving a linear inequality with one
unknown is similar to solving an equation; the unknown is isolated on one side of the inequality. As in
solving an equation, the same number can be added to or subtracted from both sides of the inequality,
or both sides of an inequality can be multiplied or divided by a positive number without changing the
truth of the inequality. However, multiplying or dividing an inequality by a negative number reverses the
order of the inequality. For example, 6 > 2, but (−1)(6) < (−1)(2).
To solve the inequality 3 x − 2 > 5 for x , isolate x by using the following steps:
x
x
x
325
3 7 (adding 2 to both sides)
7
3(dividing both sides by 3)
−>
>
>
To solve the inequality x51
2
−
− < 3 for x , isolate x by using the following steps:
x
x
x
51
23
5x 1 6 (multiplying both sides by 2)
5 5 (adding 1 to both sides)
1 (dividing both sides by 5)
−
−<
−>− −
>−
>−
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121
9. Absolute Value
e absolute value of x , denoted | x |, is de ned to be x if x ≥ 0 and − x if x < 0. Note that x2 denotes
the nonnegative square root of x
2 , and so =x2|x|.
10. Functions
An algebraic expression in one variable can be used to de ne a function of that variable. A function is
denoted by a letter such as f or g along with the variable in the expression. For example, the expression
x
3 − 5 x
2 + 2 de nes a function f that can be denoted by
fx x x() 5 2.
32
=− +
e expression z
z
27
1
+
+ de nes a function g that can be denoted by
gz z
z
() 27
1
=+
+.
e symbols “ f ( x )” or “ g ( z )” do not represent products; each is merely the symbol for an expression, and
is read “ f of x ” or “ g of z .”
Function notation provides a short way of writing the result of substituting a value for a variable. If x = 1 is
substituted in the rst expression, the result can be written f (1) = −2, and f (1) is called the “value of f at
x = 1.” Similarly, if z = 0 is substituted in the second expression, then the value of g at z = 0 is g(0) = 7.
Once a function f ( x ) is de ned, it is useful to think of the variable x as an input and f ( x ) as the
corresponding output. In any function there can be no more than one output for any given input. However,
more than one input can give the same output; for example, if h ( x ) = |x + 3|, then h (−4) = 1 = h (−2).
e set of all allowable inputs for a function is called the domain of the function. For f and g de ned
above, the domain of f is the set of all real numbers and the domain of g is the set of all numbers greater
than −1. e domain of any function can be arbitrarily speci ed, as in the function de ned by “ h ( x ) = 9 x
− 5 for 0 ≤ x ≤ 10.” Without such a restriction, the domain is assumed to be all values of x that result in
a real number when substituted into the function.
e domain of a function can consist of only the positive integers and possibly 0. For example,
an n nn() 5for 0,1,2,3,.....
2
=+ =
Such a function is called a sequence and a ( n ) is denoted by a
n . e value of the sequence a
n at n = 3 is
a33
59.60
3
2
=+= . As another example, consider the sequence de ned by b
n = (−1)n (n!) for n = 1, 2, 3, .
. . . A sequence like this is often indicated by listing its values in the order b
1 , b
2 , b
3 , . . ., b
n , . . . as follows:
−1, 2, −6, . . . , (−1)
n (n!), . . . , and (−1)
n (n!) is called the n th term of the sequence.
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4.3 Geometry
1. Lines
In geometry, the word “line” refers to a straight line that extends without end in both directions.
PQ
e line above can be referred to as line PQ or line
. e part of the line from P to Q is called a line
segment. P and Q are the endpoints of the segment. e notation
PQ is used to denote line segment PQ
and PQ is used to denote the length of the segment.
2. Intersecting Lines and Angles
If two lines intersect, the opposite angles are called vertical angles and have the same measure. In the gure
P
QS
T
R
x°y°x°
y°
∠ PRQ and ∠ SRT are vertical angles and ∠ QRS and ∠ PRT are vertical angles. Also, x + y = 180° since
PRS is a straight line.
3. Perpendicular Lines
An angle that has a measure of 90° is a right angle. If two lines intersect at right angles, the lines are
perpendicular. For example:
1 and
2 above are perpendicular, denoted by
1
⊥
2 . A right angle symbol in an angle of intersection
indicates that the lines are perpendicular.
4. Parallel Lines
If two lines that are in the same plane do not intersect, the two lines are parallel. In the gure
![](asset-82.png)
123
lines
1 and
2 are parallel, denoted by
1
2 . If two parallel lines are intersected by a third line, as
shown below, then the angle measures are related as indicated, where x + y = 180°.
y°
y°
y°
y°
x°
x°
x°x°
5. Polygons (Convex)
A polygon is a closed plane gure formed by three or more line segments, called the sides of the polygon.
Each side intersects exactly two other sides at their endpoints. e points of intersection of the sides
are vertices. e term “polygon” will be used to mean a convex polygon, that is, a polygon in which each
interior angle has a measure of less than 180° .
e following gures are polygons:
e following gures are not polygons:
A polygon with three sides is a triangle; with four sides, a quadrilateral; with ve sides, a pentagon; and
with six sides, a hexagon.
e sum of the interior angle measures of a triangle is 180°. In general, the sum of the interior angle
measures of a polygon with n sides is equal to ( n − 2)180°. For example, this sum for a pentagon is
(5 − 2)180° = (3)180° = 540°.
Note that a pentagon can be partitioned into three triangles and therefore the sum of the angle
measures can be found by adding the sum of the angle measures of three triangles.
e perimeter of a polygon is the sum of the lengths of its sides.
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e commonly used phrase “area of a triangle” (or any other plane gure) is used to mean the area of the
region enclosed by that gure.
6. Triangles
ere are several special types of triangles with important properties. But one property that all triangles
share is that the sum of the lengths of any two of the sides is greater than the length of the third side, as
illustrated below.
xy
z
x + y > z, x + z > y, and y + z > x
An equilateral triangle has all sides of equal length. All angles of an equilateral triangle have equal
measure. An isosceles triangle has at least two sides of the same length. If two sides of a triangle have the
same length, then the two angles opposite those sides have the same measure. Conversely, if two angles
of a triangle have the same measure, then the sides opposite those angles have the same length. In
isosceles triangle PQR below, x = y since PQ = QR .
y°
x°
Q
P
R
1010
A triangle that has a right angle is a right triangle. In a right triangle, the side opposite the right angle is
the hypotenuse, and the other two sides are the legs. An important theorem concerning right triangles is
the Pythagorean theorem, which states: In a right triangle, the square of the length of the hypotenuse is
equal to the sum of the squares of the lengths of the legs.
T
S
R
6
8
In the gure above, ΔRST is a right triangle, so ( RS )
2 + ( RT )
2 = ( ST )2. Here, RS = 6 and RT = 8, so
ST = 10, since 6
2 + 8
2 = 36 + 64 = 100 = ( ST )2 and ST = 100. Any triangle in which the lengths of
the sides are in the ratio 3:4:5 is a right triangle. In general, if a , b , and c are the lengths of the sides of a
triangle and a
2 + b
2 = c
2 , then the triangle is a right triangle.
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125
L
K
J
45º
2
45º
Z
Y
X
30º
3
60º
In 45°− 45°− 90° triangles, the lengths of the sides are in the ratio 1:1: 2 . For example, in ΔJKL,
if JL = 2, then JK = 2 and KL = 2 2. In 30°− 60°− 90° triangles, the lengths of the sides are in the ratio
1: 3:2. For example, in ΔXYZ, if XZ = 3, then XY = 3 3 and YZ = 6.
e altitude of a triangle is the segment drawn from a vertex perpendicular to the side opposite that
vertex. Relative to that vertex and altitude, the opposite side is called the base.
e area of a triangle is equal to:
(the length of the altitude) (the length of the base)
2
×
AD
E
B
C
8
BD = 5
In ΔABC, BD is the altitude to base AC and AE is the altitude to base BC . e area of Δ ABC is
equal to
BD AC
2
58
220.
×=×=
e area is also equal to AE BC
2
×. If Δ ABC above is isosceles and AB = BC , then altitude BD bisects
the base; that is, AD = DC = 4. Similarly, any altitude of an equilateral triangle bisects the side to which
it is drawn.
D
60º
G
E
F
30º
6
In equilateral triangle DEF, if DE = 6, then DG = 3 and EG = 3 3. e area of Δ DEF is equal to
33 6
293
×=.
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7. Quadrilaterals
A polygon with four sides is a quadrilateral. A quadrilateral in which both pairs of opposite sides are
parallel is a parallelogram. e opposite sides of a parallelogram also have equal length.
KL
M
J
N
6
4
In parallelogram JKLM , JK LM and JK LM KL JM;= and KL = JM .
e diagonals of a parallelogram bisect each other (that is, KN = NM and JN = NL).
e area of a parallelogram is equal to
(the length of the altitude) × (the length of the base).
e area of JKLM is equal to 4 × 6 = 24.
A parallelogram with right angles is a rectangle, and a rectangle with all sides of equal length is a square.
X
W
Y
Z
3
7
e perimeter of WXYZ = 2(3) + 2 (7) = 20 and the area of WXYZ is equal to 3 × 7 = 21. e diagonals
of a rectangle are equal; therefore WY XZ 949 58==+=.
P
R
S
16
12
Q
8
A quadrilateral with two sides that are parallel, as shown above, is a trapezoid. e area of trapezoid
PQRS may be calculated as follows:
QR PS
1
2(the sum of the lengths of the bases)(the height) 1
2()(8)
1
2(28 8) 112.=+=×=
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127
8. Circles
A circle is a set of points in a plane that are all located the same distance from a xed point (the center of
the circle).
A chord of a circle is a line segment that has its endpoints on the circle. A chord that passes through the
center of the circle is a diameter of the circle. A radius of a circle is a segment from the center of the circle to a
point on the circle. e words “diameter” and “radius” are also used to refer to the lengths of these segments.
e circumference of a circle is the distance around the circle. If r is the radius of the circle, then the
circumference is equal to 2
π
r, where π is approximately 22
7 or 3.14. e area of a circle of radius r is
equal to
π
r
2 .
K
P
R
J
O7
In the circle above, O is the center of the circle and JK and PR are chords. PR is a diameter and OR
is a radius. If OR = 7, then the circumference of the circle is 2
π
(7) = 14
π
and the area of the circle is
π
(7)
2 = 49
π
.
e number of degrees of arc in a circle (or the number of degrees in a complete revolution) is 360.
S
T
R
O
xº
In the circle with center O above, the length of arc RST is x
360 of the circumference of the circle; for
example, if x = 60, then arc RST has length 1
6 of the circumference of the circle.
A line that has exactly one point in common with a circle is said to be tangent to the circle, and that
common point is called the point of tangency. A radius or diameter with an endpoint at the point of
tangency is perpendicular to the tangent line, and, conversely, a line that is perpendicular to a radius or
diameter at one of its endpoints is tangent to the circle at that endpoint.
T
O
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e line above is tangent to the circle and radius OT is perpendicular to .
If each vertex of a polygon lies on a circle, then the polygon is inscribed in the circle and the circle is
circumscribed about the polygon. If each side of a polygon is tangent to a circle, then the polygon is
circumscribed about the circle and the circle is inscribed in the polygon.
Q R
SP A
B
CD
E
F
In the gure above, quadrilateral PQRS is inscribed in a circle and hexagon ABCDEF is circumscribed
about a circle.
If a triangle is inscribed in a circle so that one of its sides is a diameter of the circle, then the triangle is
a right triangle.
XZ
Y
O
In the circle above, XZ is a diameter and the measure of ∠ XYZ is 90°.
9. Rectangular Solids and Cylinders
A rectangular solid is a three‐dimensional gure formed by 6 rectangular surfaces, as shown below. Each
rectangular surface is a face. Each solid or dotted line segment is an edge, and each point at which the
edges meet is a vertex. A rectangular solid has 6 faces, 12 edges, and 8 vertices. Opposite faces are parallel
rectangles that have the same dimensions. A rectangular solid in which all edges are of equal length is a cube.
e surface area of a rectangular solid is equal to the sum of the areas of all the faces. e volume is equal to
(length) × (width) × (height);
in other words, (area of base) × (height).
QR
VU
W
T
P
4
3S
8
In the rectangular solid above, the dimensions are 3, 4, and 8. e surface area is equal to
2(3 × 4) + 2(3 × 8) + 2(4 × 8) = 136. e volume is equal to 3 × 4 × 8 = 96.
![](asset-88.png)
129
O
P
e gure above is a right circular cylinder. e two bases are circles of the same size with centers O and
P, respectively, and altitude (height) OP is perpendicular to the bases. e surface area of a right circular
cylinder with a base of radius r and height h is equal to 2(
π
r
2 ) + 2
π
rh (the sum of the areas of the two
bases plus the area of the curved surface).
e volume of a cylinder is equal to
π
r
2 h , that is,
(area of base) × (height).
8
5
In the cylinder above, the surface area is equal to
2(25 ) 2 (5)(8) 130 ,
ππ π
+=
and the volume is equal to
25 (8) 200 .
ππ
=
10. Coordinate Geometry
y
x
O
3
IV
III
I
II 2
1
213
4
–1
–2
–3
–4 –3 –2 –1
e gure above shows the (rectangular) coordinate plane. e horizontal line is called the x‐axis and the
perpendicular vertical line is called the y‐axis. e point at which these two axes intersect, designated O,
is called the origin. e axes divide the plane into four quadrants, I, II, III, and IV, as shown.
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Each point in the plane has an x‐coordinate and a y‐coordinate. A point is identi ed by an ordered pair
( x,y ) of numbers in which the x‐coordinate is the rst number and the y‐coordinate is the second number.
y
x
O
3
2
1
–1
–2
–3
2143–3–5 –4 –2 –1 5
4
5
–4
–5
Q
P
In the graph above, the (x,y) coordinates of point P are (2,3) since P is 2 units to the right of the y ‐axis
(that is, x = 2) and 3 units above the x ‐axis (that is, y = 3). Similarly, the ( x,y ) coordinates of point Q are
(−4,−3). e origin O has coordinates (0,0).
One way to nd the distance between two points in the coordinate plane is to use the Pythagorean
theorem.
y
O
S
R(–2,4)
(3,–3)
Z
x
To nd the distance between points R and S using the Pythagorean theorem, draw the triangle as
shown. Note that Z has ( x,y ) coordinates (−2,−3), RZ = 7, and ZS = 5. erefore, the distance between
R and S is equal to
7 5 74.
22
+=
For a line in the coordinate plane, the coordinates of each point on the line satisfy a linear equation of
the form y = mx + b (or the form x = a if the line is vertical). For example, each point on the line on the
next page satis es the equation yx
1
21=− + . One can verify this for the points (−2,2), (2,0), and (0,1)
by substituting the respective coordinates for x and y in the equation.
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131
y
x
O
2
1
–1
213–3 –2 –1
(–2,2)
(0,1)
(2,0)
In the equation y = mx + b of a line, the coe cient m is the slope of the line and the constant term b
is the y‐intercept of the line. For any two points on the line, the slope is de ned to be the ratio of the
di erence in the y ‐coordinates to the di erence in the x ‐coordinates. Using (−2, 2) and (2, 0) above, the
slope is
y
x
The difference in the -coordinates
The difference in the -coordinates
02
22
2
4
1
2.
()
=−
−− =−=−
e y ‐intercept is the y ‐coordinate of the point at which the line intersects the y ‐axis. For the line
above, the y ‐intercept is 1, and this is the resulting value of y when x is set equal to 0 in the equation
yx
1
21=− + . e x‐intercept is the x ‐coordinate of the point at which the line intersects the x ‐axis. e
x ‐intercept can be found by setting y = 0 and solving for x. For the line yx
1
21=− + , this gives
x
x
x
1
210
1
21
2.
−+=
−=−
=
us, the x ‐intercept is 2.
Given any two points (x
1 ,y
1 ) and (x
2 ,y
2 ) with x
1 ≠ x
2 , the equation of the line passing through these
points can be found by applying the de nition of slope. Since the slope is myy
xx
21
21
=−
−, then using a
point known to be on the line, say ( x
1 , y
1 ), any point ( x,y ) on the line must satisfy yy
xx m
1
1
−
−=, or
y − y
1 = m ( x − x
1 ). (Using ( x
2 , y
2 ) as the known point would yield an equivalent equation.) For example,
consider the points (−2,4) and (3,−3) on the line below.
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y
x
O
3
2
1
–1
–2
–3
1234
–1
–2
–4 –3
4
5
–4
–5
(–2,4)
(3,–3)
e slope of this line is 34
32
7
5
()
−−
−− =−, so an equation of this line can be found using the point (3,−3)
as follows:
yx
yx
yx
37
53
37
5
21
5
7
5
6
5
() ( )
−− =− −
+=− +
=− +
e y ‐intercept is 6
5. e x‐intercept can be found as follows:
x
x
x
07
5
6
5
7
5
6
5
6
7
=− +
=
=
Both of these intercepts can be seen on the graph.
If the slope of a line is negative, the line slants downward from left to right; if the slope is positive, the
line slants upward. If the slope is 0, the line is horizontal; the equation of such a line is of the form y = b
since m = 0. For a vertical line, slope is not de ned, and the equation is of the form x = a , where a is the
x ‐intercept.
ere is a connection between graphs of lines in the coordinate plane and solutions of two linear
equations with two unknowns. If two linear equations with unknowns x and y have a unique solution,
then the graphs of the equations are two lines that intersect in one point, which is the solution. If the
equations are equivalent, then they represent the same line with in nitely many points or solutions. If
the equations have no solution, then they represent parallel lines, which do not intersect.
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133
ere is also a connection between functions (see section 4.2.10) and the coordinate plane. If a function
is graphed in the coordinate plane, the function can be understood in di erent and useful ways.
Consider the function de ned by
fx x
7
5
6
5.
()
=− +
If the value of the function, f (x), is equated with the variable y, then the graph of the function in the
xy ‐coordinate plane is simply the graph of the equation
yx
7
5
6
5
=− +
shown above. Similarly, any function f ( x ) can be graphed by equating y with the value of the function:
yfx.
()
=
So for any x in the domain of the function f, the point with coordinates ( x , f ( x )) is on the graph of f,
and the graph consists entirely of these points.
As another example, consider a quadratic polynomial function de ned by f(x) = x
2 −1. One can plot
several points ( x , f ( x )) on the graph to understand the connection between a function and its graph:
f(x)x
–2 3
–1 0
0–1
01
32
y
x
O
2
1
–1
21–2 –1
(–2,3) (2,3)
(1,0)
(0,–1)
3
–2
(–1,0)
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If all the points were graphed for −2 ≤ x ≤ 2, then the graph would appear as follows.
y
x
O
2
1
–1
21–2 –1
3
–2
e graph of a quadratic function is called a parabola and always has the shape of the curve above,
although it may be upside down or have a greater or lesser width. Note that the roots of the equation
f ( x ) = x
2 −1 = 0 are x = 1 and x = −1; these coincide with the x ‐intercepts since x‐intercepts are
found by setting y = 0 and solving for x . Also, the y‐intercept is f (0) = −1 because this is the value of y
corresponding to x = 0. For any function f, the x ‐intercepts are the solutions of the equation f ( x ) = 0
and the y ‐intercept is the value f (0).
4.4 Word Problems
Many of the principles discussed in this chapter are used to solve word problems. e following
discussion of word problems illustrates some of the techniques and concepts used in solving such
problems.
1. Rate Problems
e distance that an object travels is equal to the product of the average speed at which it travels and
the amount of time it takes to travel that distance, that is,
Rate × Time = Distance.
Example 1: If a car travels at an average speed of 70 kilometers per hour for 4 hours, how many
kilometers does it travel?
Solution: Since rate × time = distance, simply multiply 70 km/hour × 4 hours. us, the car travels
280 kilometers in 4 hours.
To determine the average rate at which an object travels, divide the total distance traveled by the total
amount of traveling time.
Example 2: On a 400‐mile trip, Car X traveled half the distance at 40 miles per hour (mph) and the
other half at 50 mph. What was the average speed of Car X ?
Solution: First it is necessary to determine the amount of traveling time. During the rst 200 miles, the
car traveled at 40 mph; therefore, it took 200
40 = 5 hours to travel the rst 200 miles.
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135
During the second 200 miles, the car traveled at 50 mph; therefore, it took 200
50 = 4 hours to travel the
second 200 miles. us, the average speed of Car X was 400
944 4
9
= mph. Note that the average speed is
not 40 50
245
+=.
Some rate problems can be solved by using ratios.
Example 3: If 5 shirts cost $44, then, at this rate, what is the cost of 8 shirts?
Solution: If c is the cost of the 8 shirts, then c
5
44
8
=. Cross multiplication results in the equation
c
c
5 8 44 352
352
570.40
=× =
==
e 8 shirts cost $70.40.
2. Work Problems
In a work problem, the rates at which certain persons or machines work alone are usually given, and it is
necessary to compute the rate at which they work together (or vice versa).
e basic formula for solving work problems is rsh
11 1
+=, where r and s are, for example, the number
of hours it takes Rae and Sam, respectively, to complete a job when working alone, and h is the number
of hours it takes Rae and Sam to do the job when working together. e reasoning is that in 1 hour Rae
does r
1 of the job, Sam does s
1 of the job, and Rae and Sam together do h
1 of the job.
Example 1: If Machine X can produce 1,000 bolts in 4 hours and Machine Y can produce 1,000 bolts in
5 hours, in how many hours can Machines X and Y, working together at these constant rates, produce
1,000 bolts?
Solution:
h
h
h
h
h
1
4
1
5
1
5
20
4
20
1
9
20
1
920
20
922
9
+=
+=
=
=
==
Working together, Machines X and Y can produce 1,000 bolts in 22
9 hours.
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Example 2: If Art and Rita can do a job in 4 hours when working together at their respective constant
rates and Art can do the job alone in 6 hours, in how many hours can Rita do the job alone?
Solution:
R
R
R
RR
R
R
1
6
11
4
6
6
1
4
4246
24 2
12
+=
+=
+=
=
=
Working alone, Rita can do the job in 12 hours.
3. Mixture Problems
In mixture problems, substances with di erent characteristics are combined, and it is necessary to
determine the characteristics of the resulting mixture.
Example 1: If 6 pounds of nuts that cost $1.20 per pound are mixed with 2 pounds of nuts that cost
$1.60 per pound, what is the cost per pound of the mixture?
Solution: e total cost of the 8 pounds of nuts is
e cost per pound is
6($1.20) 2($1.60) $10.40.
$10.40
8$1.30.
+=
=
Example 2: How many liters of a solution that is 15 percent salt must be added to 5 liters of a solution
that is 8 percent salt so that the resulting solution is 10 percent salt?
Solution: Let n represent the number of liters of the 15% solution. e amount of salt in the 15%
solution [0.15 n ] plus the amount of salt in the 8% solution [(0.08)(5)] must be equal to the amount of
salt in the 10% mixture [0.10( n + 5)]. erefore,
nn
nn
n
n
0.15 0.08(5) 0.10( 5)
15 40 10 50
510
2liters
+=+
+= +
=
=
Two liters of the 15% salt solution must be added to the 8% solution to obtain the 10% solution.
4. Interest Problems
Interest can be computed in two basic ways. With simple annual interest, the interest is computed on
the principal only and is equal to (principal) × (interest rate) × (time). If interest is compounded, then
interest is computed on the principal as well as on any interest already earned.
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137
Example 1: If $8,000 is invested at 6 percent simple annual interest, how much interest is earned after
3 months?
Solution: Since the annual interest rate is 6%, the interest for 1 year is
e interest earned in 3 months is
0.06 $8,000 $480.
3
12 $480 $120.
()( )
()
=
=
Example 2: If $10,000 is invested at 10 percent annual interest, compounded semiannually, what is the
balance after 1 year?
Solution: e balance after the rst 6 months would be
e balance after one year would be
10, 000 (10, 000)(0.05) $10, 500.
10, 500 (10, 500)(0.05) $11, 025.
+=
+=
Note that the interest rate for each 6‐month period is 5%, which is half of the 10% annual rate. e
balance after one year can also be expressed as
10, 000 1 0.10
2dollars.
2
+
⎛
⎝⎞
⎠
5. Discount
If a price is discounted by n percent, then the price becomes (100 − n ) percent of the original price.
Example 1: A certain customer paid $24 for a dress. If that price represented a 25 percent discount on
the original price of the dress, what was the original price of the dress?
Solution: If p is the original price of the dress, then 0.75 p is the discounted price and 0.75 p = $24, or
p = $32. e original price of the dress was $32.
Example 2: e price of an item is discounted by 20 percent and then this reduced price is discounted by
an additional 30 percent. ese two discounts are equal to an overall discount of what percent?
Solution: If p is the original price of the item, then 0.8 p is the price after the rst discount. e price
after the second discount is (0.7)(0.8) p = 0.56 p . is represents an overall discount of 44 percent
(l00% − 56%).
6. Profi t
Gross pro t is equal to revenues minus expenses, or selling price minus cost.
Example: A certain appliance costs a merchant $30. At what price should the merchant sell the
appliance in order to make a gross pro t of 50 percent of the cost of the appliance?
Solution: If s is the selling price of the appliance, then s − 30 = (0.5)(30), or s = $45. e merchant
should sell the appliance for $45.
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7. Sets
If S is the set of numbers 1, 2, 3, and 4, you can write S = {l, 2, 3, 4}. Sets can also be represented by
Venn diagrams. at is, the relationship among the members of sets can be represented by circles.
Example 1: Each of 25 people is enrolled in history, mathematics, or both. If 20 are enrolled in history
and 18 are enrolled in mathematics, how many are enrolled in both history and mathematics?
Solution: e 25 people can be divided into three sets: those who study history only, those who study
mathematics only, and those who study history and mathematics. us a Venn diagram may be drawn
as follows, where n is the number of people enrolled in both courses, 20 − n is the number enrolled in
history only, and 18 − n is the number enrolled in mathematics only.
20 – n18 – nn
History Mathematics
Since there is a total of 25 people, (20 − n ) + n + (18 − n ) = 25, or n = 13. irteen people are enrolled
in both history and mathematics. Note that 20 + 18 − 13 = 25, which is the general addition rule for
two sets (see section 4.1.9).
Example 2: In a certain production lot, 40 percent of the toys are red and the remaining toys are green.
Half of the toys are small and half are large. If 10 percent of the toys are red and small, and 40 toys are
green and large, how many of the toys are red and large?
Solution: For this kind of problem, it is helpful to organize the information in a table:
Red Green Total
Small 10% 50%
Large 50%
Total 40% 60% 100%
e numbers in the table are the percentages given. e following percentages can be computed on the
basis of what is given:
Red Green Total
Small 10% 40% 50%
Large 30% 20% 50%
Total 40% 60% 100%
Since 20% of the number of toys ( n ) are green and large, 0.20 n = 40 (40 toys are green and large), or
n = 200. erefore, 30% of the 200 toys, or (0.3)(200) = 60, are red and large.
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8. Geometry Problems
e following is an example of a word problem involving geometry.
Example:
200 meters
200 meters
e gure above shows an aerial view of a piece of land. If all angles shown are right angles, what is the
perimeter of the piece of land?
Solution: For reference, label the gure as
QR
ST
S
U
P
V
W
If all the angles are right angles, then QR + ST + UV = PW , and RS + TU + VW = PQ . Hence, the
perimeter of the land is 2 PW + 2 PQ = 2 × 200 + 2 × 200 = 800 meters.
9. Measurement Problems
Some questions on the GMAT involve metric units of measure, whereas others involve English units of
measure. However, except for units of time, if a question requires conversion from one unit of measure
to another, the relationship between those units will be given.
Example: A train travels at a constant rate of 25 meters per second. How many kilometers does it travel
in 5 minutes? (1 kilometer = 1,000 meters)
Solution: In 1 minute the train travels (25)(60) = 1,500 meters, so in 5 minutes it travels 7,500 meters.
Since 1 kilometer = 1,000 meters, it follows that 7,500 meters equals 7,500
1,000 , or 7.5 kilometers.
4.4 Math Review Word Problems
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10. Data Interpretation
Occasionally a question or set of questions will be based on data provided in a table or graph. Some
examples of tables and graphs are given below.
Example 1:
Population by Age Group
(in thousands)
Age Population
17 years and under 63,376
18−44 years 86,738
45−64 years 43,845
65 years and over 24,054
How many people are 44 years old or younger?
Solution: e gures in the table are given in thousands. e answer in thousands can be obtained by
adding 63,376 thousand and 86,738 thousand. e result is 150,114 thousand, which is 150,114,000.
Example 2:
AVERAGE TEMPERATURE AND
PRECIPITATION IN CITY X
30
25
20
15
10
5
0
12
10
8
6
4
2
0
Precipitation
(right-hand scale)
Temperature
(left-hand scale)
Precipitation in
Centimeters
Temperature in
Degrees Celsius
January April July October
What are the average temperature and precipitation in City X during April?
Solution: Note that the scale on the left applies to the temperature line graph and the one on the right
applies to the precipitation line graph. According to the graph, during April the average temperature is
approximately 14° Celsius and the average precipitation is approximately 8 centimeters.
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4.4 Math Review Word Problems
Example 3:
DISTRIBUTION OF AL’S WEEKLY NET SALARY
Food
15% Rent and
Utilities
10%
30%
Savings
25% Other
20%
Fuel and
Insurance
for Automobile
Al’s weekly net salary is $350. To how many of the categories listed was at least $80 of Al’s weekly net
salary allocated?
Solution: In the circle graph, the relative sizes of the sectors are proportional to their corresponding
values and the sum of the percents given is 100%. Note that 80
350 is approximately 23%, so at least $80
was allocated to each of 2 categories—Rent and Utilities, and Savings—since their allocations are each
greater than 23%.
142
5.0 Problem Solving
143
5.0 Problem Solving
5.0 Problem Solving
e Quantitative section of the GMAT ® exam uses problem solving and data sufficiency questions to
gauge your skill level. is chapter focuses on problem solving questions. Remember that quantitative
questions require knowledge of the following:
• Arithmetic
• Elementary algebra
• Commonly known concepts of geometry
Problem solving questions are designed to test your basic mathematical skills and understanding of
elementary mathematical concepts, as well as your ability to reason quantitatively, solve quantitative
problems, and interpret graphic data. e mathematics knowledge required to answer the questions
is no more advanced than what is generally taught in secondary school (or high school) mathematics
classes.
In these questions, you are asked to solve each problem and select the best of the five answer choices
given. Begin by reading the question thoroughly to determine exactly what information is given and
to make sure you understand what is being asked. Scan the answer choices to understand your options.
If the problem seems simple, take a few moments to see whether you can determine the answer. en,
check your answer against the choices provided.
If you do not see your answer among the choices, or if the problem is complicated, take a closer look at
the answer choices and think again about what the problem is asking. See whether you can eliminate
some of the answer choices and narrow down your options. If you are still unable to narrow the answer
down to a single choice, reread the question. Keep in mind that the answer will be based solely on the
information provided in the question—don’t allow your own experience and assumptions to interfere
with your ability to find the correct answer to the question.
If you find yourself stuck on a question or unable to select the single correct answer, keep in mind that
you have about two minutes to answer each quantitative question. You may run out of time if you take
too long to answer any one question; you may simply need to pick the answer that seems to make the
most sense. Although guessing is generally not the best way to achieve a high GMAT score, making
an educated guess is a good strategy for answering questions you are unsure of. Even if your answer to
a particular question is incorrect, your answers to other questions will allow the test to accurately gauge
your ability level.
e following pages include test‐taking strategies, directions that will apply to questions of this type,
sample questions, an answer key, and explanations for all the problems. ese explanations present
problem solving strategies that could be helpful in answering the questions.
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5.1 Test-Taking Strategies
1. Pace yourself.
Consult the on‐screen timer periodically. Work as carefully as possible, but do not spend
valuable time checking answers or pondering problems that you find difficult.
2. Use the erasable notepad provided at the test center.
Working a problem out may help you avoid errors in solving the problem. If diagrams or figures
are not presented, it may help to draw your own.
3. Read each question carefully to determine what is being asked.
For word problems, take one step at a time, reading each sentence carefully and translating the
information into equations or other useful mathematical representations.
4. Scan the answer choices before attempting to answer a question.
Scanning the answers can prevent you from putting answers in a form that is not given
(e.g., finding the answer in decimal form, such as 0.25, when the choices are given in fractional
form, such as 1
4). Also, if the question requires approximations, a shortcut could serve well
(e.g., you may be able to approximate 48 percent of a number by using half ).
5. Don’t waste time trying to solve a problem that is too difficult for you.
Make your best guess and then move on to the next question.
5.2 The Directions
ese directions are very similar to those you will see for problem solving questions when you take the
GMAT exam. If you read them carefully and understand them clearly before sitting for the GMAT
exam, you will not need to spend too much time reviewing them once the test begins.
Solve the problem and indicate the best of the answer choices given.
Numbers: All numbers used are real numbers.
Figures: A figure accompanying a problem solving question is intended to provide information useful
in solving the problem. Figures are drawn as accurately as possible. Exceptions will be clearly noted.
Lines shown as straight are straight, and lines that appear jagged are also straight. e positions of
points, angles, regions, etc., exist in the order shown, and angle measures are greater than zero. All
figures lie in a plane unless otherwise indicated.
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1. The price of a coat in a certain store is $500. If the
price of the coat is to be reduced by $150, by what
percent is the price to be reduced?
(A) 10%
(B) 15%
(C) 20%
(D) 25%
(E) 30%
2. On a vacation, Rose exchanged $500.00 for euros
at an exchange rate of 0.80euro per dollar and
spent 3
4 of the euros she received. If she exchanged
the remaining euros for dollars at an exchange rate
of $1.20per euro, what was the dollar amount she
received?
(A) $60.00
(B) $80.00
(C) $100.00
(D) $120.00
(E) $140.00
x
v
x
x
x
x
y
y
y
w
v
w
3. Each of the 12 squares shown is labeled x, y, v, or w.
What is the ratio of the number of these squares labeled
x or y to the number of these squares labeled v or w?
(A) 1:2
(B) 2:3
(C) 4:3
(D) 3:2
(E) 2:1
4.
1
3
1
2
5
6
1
5
1
4
9
20
+−++− =
(A) 0
(B) 2
15
(C) 2
5
(D) 9
20
(E) 5
6
5. Bouquets are to be made using white tulips and red
tulips, and the ratio of the number of white tulips to
the number of red tulips is to be the same in each
bouquet. If there are 15 white tulips and 85 red tulips
available for the bouquets, what is the greatest number
of bouquets that can be made using all the tulips
available?
(A) 3
(B) 5
(C) 8
(D) 10
(E) 13
6. 125% of 5 =
(A) 5.125
(B) 5.25
(C) 6
(D) 6.125
(E) 6.25
5.3 Practice Questions
Solve the problem and indicate the best of the answer choices given.
Numbers: All numbers used are real numbers.
Figures: A fi gure accompanying a problem solving question is intended to provide information useful
in solving the problem. Figures are drawn as accurately as possible. Exceptions will be clearly
noted. Lines shown as straight are straight, and lines that appear jagged are also straight. The
positions of points, angles, regions, etc., exist in the order shown, and angle measures are
greater than zero. All fi gures lie in a plane unless otherwise indicated.
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147
7. Today Rebecca, who is 34 years old, and her daughter,
who is 8 years old, celebrate their birthdays. How
many years will pass before Rebecca’s age is twice her
daughter’s age?
(A) 10
(B) 14
(C) 18
(D) 22
(E) 26
8. When traveling at a constant speed of 32miles per hour,
a certain motorboat consumes 24gallons of fuel
per hour. What is the fuel consumption of this boat at
this speed measured in miles traveled per gallon of fuel?
(A) 2
3
(B) 3
4
(C) 4
5
(D) 4
3
(E) 3
2
9. A case contains c cartons. Each carton contains
b boxes, and each box contains 100 paper clips.
How many paper clips are contained in 2 cases?
(A) 100 bc
(B)
100b
c
(C) 200 b c
(D)
200b
c
(E)
200
bc
10. A technician makes a round‐trip to and from a certain
service center by the same route. If the technician
completes the drive to the center and then completes
10percent of the drive from the center, what percent
of the round‐trip has the technician completed?
(A) 5%
(B) 10%
(C) 25%
(D) 40%
(E) 55%
11. Raffle tickets numbered consecutively from 101
through 350 are placed in a box. What is the
probability that a ticket selected at random will have a
number with a hundreds digit of 2?
(A) 2
5
(B) 2
7
(C) 33
88
(D) 99
250
(E) 100
249
12. When Leo imported a certain item, he paid a 7 percent
import tax on the portion of the total value of the item
in excess of $1,000. If the amount of the import tax
that Leo paid was $87.50, what was the total value of
the item?
(A) $1,600
(B) $1,850
(C) $2,250
(D) $2,400
(E) $2,750
13. A collection of 16coins, each with a face value of
either 10cents or 25cents, has a total face value of
$2.35. How many of the coins have a face value of
25cents?
(A) 3
(B) 5
(C) 7
(D) 9
(E) 11
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14. The numbers of cars sold at a certain dealership on
six of the last seven business days were 4, 7, 2, 8, 3,
and 6, respectively. If the number of cars sold on the
seventh business day was either 2, 4, or 5, for which
of the three values does the average (arithmetic mean)
number of cars sold per business day for the seven
business days equal the median number of cars sold
per day for the seven days?
I . 2
II. 4
III. 5
(A) II only
(B) III only
(C) I and II only
(D) II and III only
(E) I, II, and III
15. If it is assumed that 60 percent of those who receive
a questionnaire by mail will respond and 300 responses
are needed, what is the minimum number of
questionnaires that should be mailed?
(A) 400
(B) 420
(C) 480
(D) 500
(E) 600
16. If 1 < x < y < z, which of the following has the greatest
value?
(A) z(x + 1)
(B) z(y + 1)
(C) x(y + z)
(D) y(x + z)
(E) z(x + y)
17. A rectangular garden is to be twice as long as it is
wide. If 360 yards of fencing, including the gate, will
completely enclose the garden, what will be the length
of the garden, in yards?
(A) 120
(B) 140
(C) 160
(D) 180
(E) 200
18. A rectangular floor that measures 8 meters by
10 meters is to be covered with carpet squares that
each measure 2 meters by 2 meters. If the carpet
squares cost $12 apiece, what is the total cost for the
number of carpet squares needed to cover the floor?
(A) $200
(B) $240
(C) $480
(D) $960
(E) $1,920
19. If 893 × 78 = p , which of the following is equal to
893 × 79?
(A) p + 1
(B) p + 78
(C) p + 79
(D) p + 893
(E) p + 894
20. Thabo owns exactly 140books, and each book is
either paperback ction, paperback non ction, or
hardcover non ction. If he owns 20more paperback
non ction books than hardcover non ction books, and
twice as many paperback ction books as paperback
non ction books, how many hardcover non ction
books does Thabo own?
(A) 10
(B) 20
(C) 30
(D) 40
(E) 50
21. If the average (arithmetic mean) of the four numbers
3, 15, 32, and ( N + 1) is 18, then N =
(A) 19
(B) 20
(C) 21
(D) 22
(E) 29
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149
22. Abdul, Barb, and Carlos all live on the same straight
road, on which their school is also located. The school
is halfway between Abdul’s house and Barb’s house.
Barb’s house is halfway between the school and
Carlos’s house. If the school is 4 miles from Carlos’s
house, how many miles is Abdul’s house from Carlos’s
house?
(A) 11
3
(B) 2
(C) 4
(D) 6
(E) 8
23. During a certain time period, Car X traveled north
along a straight road at a constant rate of 1 mile per
minute and used fuel at a constant rate of 5 gallons
every 2 hours. During this time period, if Car X used
exactly 3.75 gallons of fuel, how many miles did Car X
travel?
(A) 36
(B) 37.5
(C) 40
(D) 80
(E) 90
24. Cheryl purchased 5 identical hollow pine doors and
6identical solid oak doors for the house she is
building. The regular price of each solid oak door
was twice the regular price of each hollow pine door.
However, Cheryl was given a discount of 25% off the
regular price of each solid oak door. If the regular price
of each hollow pine door was $40, what was the total
price of all 11doors?
(A) $320
(B) $540
(C) $560
(D) $620
(E) $680
25. If 1
2
11
2
y−<, which of the following could be a value
of y ?
(A) –11
(B) 11
2
−
(C) 11
2
(D) 11
(E) 22
B
CD
120°
A
Note: Not drawn to scale.
26. In the gure shown, AC = 2 and BD = DC = 1. What is
the measure of angle ABD?
(A) 15°
(B) 20°
(C) 30°
(D) 40°
(E) 45°
27. If k
2 = m
2 , which of the following must be true?
(A) k = m
(B) k = –m
(C) k = |m|
(D) k = –|m|
(E) |k| = |m|
28. Makoto, Nishi, and Ozuro were paid a total of $780
for waxing the oors at their school. Each was paid in
proportion to the number of hours he or she worked. If
Makoto worked 15hours, Nishi worked 20hours, and
Ozuro worked 30hours, how much was Makoto paid?
(A) $52
(B) $117
(C) $130
(D) $180
(E) $234
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6
8
PQ
R
29. The gure above shows a path around a triangular
piece of land. Mary walked the distance of 8 miles
from P to Q and then walked the distance of 6miles
from Q to R . If Ted walked directly from P to R , by what
percent did the distance that Mary walked exceed the
distance that Ted walked?
(A) 30%
(B) 40%
(C) 50%
(D) 60%
(E) 80%
30. At a supermarket, John spent 1
2 of his money on fresh
fruits and vegetables, 1
3 on meat products, and 1
10 on
bakery products. If he spent the remaining $6 on
candy, how much did John spend at the supermarket?
(A) $60
(B) $80
(C) $90
(D) $120
(E) $180
31. If (1 – 1.25) N = 1, then N =
(A) –400
(B) –140
(C) –4
(D) 4
(E) 400
32. A carpenter constructed a rectangular sandbox with
a capacity of 10 cubic feet. If the carpenter were to
make a similar sandbox twice as long, twice as wide,
and twice as high as the rst sandbox, what would be
the capacity, in cubic feet, of the second sandbox?
(A) 20
(B) 40
(C) 60
(D) 80
(E) 100
33. The quotient when a certain number is divided by 2
3 is
9
2. What is the number?
(A) 4
27
(B)
1
3
(C) 3
(D) 6
(E) 27
4
34. If a sphere with radius r is inscribed in a cube with
edges of length e, which of the following expresses the
relationship between r and e?
(A) r = 1
2e
(B) r = e
(C) r = 2e
(D) r = e
(E) r = 1
4
2
e
35. If 2 x + y = 7 and x + 2 y = 5, then 3
xy+=
(A) 1
(B) 4
3
(C)
17
5
(D)
18
5
(E) 4
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151
36. City X has a population 4 times as great as the
population of City Y, which has a population twice as
great as the population of City Z. What is the ratio of
the population of City X to the population of City Z?
(A) 1:8
(B) 1:4
(C) 2:1
(D) 4:1
(E) 8:1
Tides at Bay Cove on July 13
11:30 a.m.
2.2 ft
4:30 a.m.
0.3 ft
6 p.m.
–0.5 ft
6 a.m.
–1
0
1
2
3
noon midnight
time
height of tide
37. The graph above shows the height of the tide, in feet,
above or below a baseline. Which of the following is
closest to the difference, in feet, between the heights
of the highest and lowest tides on July 13 at Bay Cove?
(A) 1.7
(B) 1.9
(C) 2.2
(D) 2.5
(E) 2.7
38. A manufacturer of a certain product can expect that
between 0.3 percent and 0.5 percent of the units
manufactured will be defective. If the retail price is
$2,500 per unit and the manufacturer offers a full
refund for defective units, how much money can the
manufacturer expect to need to cover the refunds on
20,000 units?
(A) Between $15,000 and $25,000
(B) Between $30,000 and $50,000
(C) Between $60,000 and $100,000
(D) Between $150,000 and $250,000
(E) Between $300,000 and $500,000
house
patio
40ft
35ft
20ft
15ft
39. A at patio was built alongside a house as shown in the
gure above. If all angles are right angles, what is the
area of the patio in square feet?
(A) 800
(B) 875
(C) 1,000
(D) 1,100
(E) 1,125
40. The sum of the weekly salaries of 5 employees is
$3,250. If each of the 5salaries is to increase by
10percent, then the average (arithmetic mean) weekly
salary per employee will increase by
(A) $52.50
(B) $55.00
(C) $57.50
(D) $62.50
(E) $65.00
41. A student’s average (arithmetic mean) test score on
4 tests is 78. What must be the student’s score
on a 5th test for the student’s average score on the
5 tests to be 80?
(A) 80
(B) 82
(C) 84
(D) 86
(E) 88
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42. Last week Chris earned x dollars per hour for the rst
40hours worked plus 22dollars per hour for each
hour worked beyond 40hours. If last week Chris
earned a total of 816dollars by working 48hours,
what is the value of x?
(A) 13
(B) 14
(C) 15
(D) 16
(E) 17
B
C
A
(
y
+ 10)°
y
°
43. In the gure above, what is the ratio of the measure of
angle B to the measure of angle A ?
(A) 2 to 3
(B) 3 to 4
(C) 3 to 5
(D) 4 to 5
(E) 5 to 6
44. If n is a prime number greater than 3, what is the
remainder when n
2 is divided by 12?
(A) 0
(B) 1
(C) 2
(D) 3
(E) 5
45.
+
−
+
=
1
11
3
1
11
2
(A) 1
3
−
(B) 1
6
−
(C) 1
12
−
(D) 1
12
(E) 1
3
46. The positive two‐digit integers x and y have the same
digits, but in reverse order. Which of the following must
be a factor of x + y ?
(A) 6
(B) 9
(C) 10
(D) 11
(E) 14
47. In a certain sequence of 8 numbers, each number
after the rst is 1 more than the previous number. If
the rst number is –5, how many of the numbers in the
sequence are positive?
(A) None
(B) One
(C) Two
(D) Three
(E) Four
48. A total of s oranges are to be packaged in boxes that
will hold r oranges each, with no oranges left over.
When n of these boxes have been completely lled,
what is the number of boxes that remain to be lled?
(A) s – nr
(B)
sn
r
−
(C) rs – n
(D)
s
nr−
(E)
s
rn−
49. If 0 < a < b < c , which of the following statements
must be true?
I. 2 a > b + c
II. c – a > b – a
III.
c
a
b
a
<
(A) I only
(B) II only
(C) III only
(D) I and II
(E) II and III
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153
50. In the xy-plane, the origin O is the midpoint of line
segment PQ. If the coordinates of P are (r,s), what are
the coordinates of Q?
(A) (r,s)
(B) (s,–r)
(C) (–s,–r)
(D) (–r,s)
(E) (–r,–s)
51. Which of the following equations is NOT equivalent to
10 y
2 = ( x + 2)( x – 2)?
(A) 30 y
2 = 3 x
2 – 12
(B) 20 y
2 = (2 x – 4)( x + 2)
(C) 10 y
2 + 4 = x
2
(D) 5 y
2 = x
2 – 2
(E) y
2 = 4
10
2
x−
Monday Tuesday Wednesday Thursday
Company A 45 55 50 50
Company B 10 30 30 10
Company C 34 28 28 30
Company D 39 42 41 38
Company E 50 60 60 70
52. The table shows the numbers of packages shipped
daily by each of ve companies during a 4‐day period.
The standard deviation of the numbers of packages
shipped daily during the period was greatest for which
of the ve companies?
(A) A
(B) B
(C) C
(D) D
(E) E
53. CompanyQ plans to make a new product next year
and sell each unit of this new product at a selling price
of $2. The variable costs per unit in each production
run are estimated to be 40% of the selling price, and
the xed costs for each production run are estimated
to be $5,040. Based on these estimated costs, how
many units of the new product will CompanyQ need to
make and sell in order for their revenue to equal their
total costs for each production run?
(A) 4,200
(B) 3,150
(C) 2,520
(D) 2,100
(E) 1,800
S
AE
D
C
B
54. The dial shown above is divided into equal‐sized
intervals. At which of the following letters will the
pointer stop if it is rotated clockwise from S through
1,174 intervals?
(A) A
(B) B
(C) C
(D) D
(E) E
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Estimated Number of Home-Schooled
Students by State, January 2001
State Number (in thousands)
A 181
B 125
C 103
D 79
E 72
55. According to the table shown, the estimated number
of home-schooled students in State A is approximately
what percent greater than the number in State D?
(A) 25%
(B) 55%
(C) 100%
(D) 125%
(E) 155%
x
y
O
IVIII
II I
56. The graph of the equation xy = k , where k < 0, lies in
which two of the quadrants shown above?
(A) I and II
(B) I and III
(C) II and III
(D) II and IV
(E) III and IV
57. When n liters of fuel were added to a tank that was
already 1
3 full, the tank was lled to 7
9 of its capacity. In
terms of n , what is the capacity of the tank, in liters?
(A)
10
9n
(B)
4
3n
(C)
3
2n
(D)
9
4n
(E)
7
3n
w ft
w ft
100 ft
150 ft
Note: Not drawn to scale.
58. The smaller rectangle in the gure above represents
the original size of a parking lot before its length
and width were each extended by w feet to make
the larger rectangular lot shown. If the area of the
enlarged lot is twice the area of the original lot, what is
the value of w ?
(A) 25
(B) 50
(C) 75
(D) 100
(E) 200
59. 1
0.75 1−=
(A) –4
(B) –0.25
(C) 0.25
(D) 0.75
(E) 4
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5.3 Problem Solving Practice Questions
155
60. Kevin invested $8,000for one year at a simple annual
interest rate of 6percent and invested $10,000for
one year at an annual interest rate of 8percent
compounded semiannually. What is the total amount of
interest that Kevin earned on the two investments?
(A) $880
(B) $1,088
(C) $1,253
(D) $1,280
(E) $1,296
61. The harvest yield from a certain apple orchard was
350bushels of apples. If x of the trees in the orchard
each yielded 10 bushels of apples, what fraction of the
harvest yield was from these x trees?
(A)
35
x
(B)
135
x
−
(C) 10 x
(D) 35 – x
(E) 350 – 10 x
62. If n is an integer, which of the following must be even?
(A) n + 1
(B) n + 2
(C) 2 n
(D) 2 n + 1
(E) 2
n
63. The sum 7
8
1
9
+ is between
(A)
1
2and 3
4
(B)
3
4and1
(C)
1and11
4
(D)
11
4and 11
2
(E)
11
2and 2
64. Car X averages 25.0 miles per gallon of gasoline
and Car Y averages 11.9miles per gallon. If each car
is driven 12,000 miles, approximately how many more
gallons of gasoline will Car Y use than Car X?
(A) 320
(B) 480
(C) 520
(D) 730
(E) 920
65. If y is an integer, then the least possible value of
23 5y− is
(A) 1
(B) 2
(C) 3
(D) 4
(E) 5
66.
80 125+=
(A)
95
(B) 20 5
(C) 41 5
(D) 205
(E) 100
3ykx=+
67. In the equation above, k is a constant. If y = 17 when
x = 2, what is the value of y when x = 4?
(A) 34
(B) 31
(C) 14
(D) 11
(E) 7
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GMAT® Offi cial Guide 2018
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68. Which of the following is greatest?
(A) 10 3
(B) 94
(C) 85
(D) 76
(E) 67
69. Al and Ben are drivers for SD Trucking Company. One
snowy day, Ben left SD at 8:00 a.m. heading east and
Al left SD at 11:00a.m. heading west. At a particular
time later that day, the dispatcher retrieved data
from SD’s vehicle tracking system. The data showed
that, up to that time, Al had averaged 40miles per
hour and Ben had averaged 20miles per hour. It also
showed that Al and Ben had driven a combined total
of 240miles. At what time did the dispatcher retrieve
data from the vehicle tracking system?
(A) 1:00 p.m.
(B) 2:00 p.m.
(C) 3:00 p.m.
(D) 5:00 p.m.
(E) 6:00 p.m.
70. Of the land owned by a farmer, 90 percent was
cleared for planting. Of the cleared land, 40 percent
was planted with soybeans and 50 percent of the
cleared land was planted with wheat. If the remaining
720 acres of cleared land was planted with corn, how
many acres did the farmer own?
(A) 5,832
(B) 6,480
(C) 7,200
(D) 8,000
(E) 8,889
71. At the start of an experiment, a certain population
consisted of 3 animals. At the end of each month after
the start of the experiment, the population size was
double its size at the beginning of that month. Which of
the following represents the population size at the end
of 10 months?
(A)
23
(B) 32
(C) 2(3
10 )
(D) 3(2
10 )
(E) 3(10
2 )
72. If
1
3
1
4
1
5
1
6
1
9
1
12
1
15
1
18 ,r+++
⎛
⎝
⎜⎞
⎠
⎟= +++
⎛
⎝
⎜⎞
⎠
⎟ then r =
(A)
1
3
(B)
4
3
(C) 3
(D) 4
(E) 12
73. If x and y are positive integers such that y is a multiple
of 5 and 3 x + 4 y = 200, then x must be a multiple of
which of the following?
(A) 3
(B) 6
(C) 7
(D) 8
(E) 10
74. Which of the following expressions can be written as
an integer?
I.
82 82 2
)
+
⎛
⎝
⎜
II.
82 82
(
)
()
III.
82 82
82
(
)( )
(A) None
(B) I only
(C) III only
(D) I and II
(E) I and III
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5.3 Problem Solving Practice Questions
157
75. Four staff members at a certain company worked
on a project. The amounts of time that the four staff
members worked on the project were in the ratio 2 to
3 to 5 to 6. If one of the four staff members worked
on the project for 30hours, which of the following
CANNOT be the total number of hours that the four
staff members worked on the project?
(A) 80
(B) 96
(C) 160
(D) 192
(E) 240
76. Pumping alone at their respective constant rates, one
inlet pipe lls an empty tank to1
2 of capacity in 3 hours
and a second inlet pipe lls the same empty tank to
2
3 of capacity in 6 hours. How many hours will it take
both pipes, pumping simultaneously at their respective
constant rates, to ll the empty tank to capacity?
(A) 3.25
(B) 3.6
(C) 4.2
(D) 4.4
(E) 5.5
77. In the xy ‐coordinate plane, which of the following points
must lie on the line kx + 3 y = 6 for every possible value
of k ?
(A) (1,1)
(B) (0,2)
(C) (2,0)
(D) (3,6)
(E) (6,3)
78. If 2
x – 2 < 0, which of the following speci es all the
possible values of x ?
(A) 02x<<
(B)
02x<<
(C) 22x−<<
(D) 20x−< <
(E) 22x−< <
Book number Pages in book Total pages read
1 253 253
2 110 363
3 117 480
4 170 650
5 155 805
6 50 855
7 205 1,060
8 70 1,130
9 165 1,295
10 105 1,400
11 143 1,543
12 207 1,750
79. Shawana made a schedule for reading books during
4weeks (28days) of her summer vacation. She has
checked out 12books from the library. The number of
pages in each book and the order in which she plans to
read the books are shown in the table above. She will
read exactly 50pages each day. The only exception
will be that she will never begin the next book on the
same day that she nishes the previous one, and
therefore on some days she may read fewer than
50pages. At the end of the 28thday, how many books
will Shawana have nished?
(A) 7
(B) 8
(C) 9
(D) 10
(E) 11
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GMAT® Offi cial Guide 2018
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80. In Western Europe, x bicycles were sold in each of
the years 1990 and 1993. The bicycle producers of
Western Europe had a 42percent share of this market
in 1990 and a 33 percent share in 1993. Which of the
following represents the decrease in the annual number
of bicycles produced and sold in Western Europe from
1990 to 1993?
(A) 9% of 100
x
(B) 14% of 100
x
(C) 75% of 100
x
(D) 9% of x
(E) 14% of x
81. If k is a positive integer, what is the remainder when
(k+2)(k3–k) is divided by 6?
(A) 0
(B) 1
(C) 2
(D) 3
(E) 4
82. Which of the following fractions is closest to 1
2?
(A)
4
7
(B)
5
9
(C) 6
11
(D) 7
13
(E) 9
16
83. If p ≠0 and p –12
p
p
−=r
p, then r =
(A) p + 1
(B) 2 p – 1
(C) p
2 + 1
(D) 2 p
2 – 1
(E) p
2 + p – 1
84. If the range of the six numbers 4, 3, 14, 7, 10, and
x is 12, what is the difference between the greatest
possible value of x and the least possible value of x ?
(A) 0
(B) 2
(C) 12
(D) 13
(E) 15
85. What number is 108 more than two-thirds of itself?
(A) 72
(B) 144
(C) 162
(D) 216
(E) 324
86. A doctor prescribed 18cubic centimeters of a certain
drug to a patient whose body weight was 120pounds.
If the typical dosage is 2cubic centimeters per
15pounds of body weight, by what percent was the
prescribed dosage greater than the typical dosage?
(A) 8%
(B) 9%
(C) 11%
(D) 12.5%
(E) 14.8%
87. Company P had 15 percent more employees in
December than it had in January. If Company P had
460 employees in December, how many employees
did it have in January?
(A) 391
(B) 400
(C) 410
(D) 423
(E) 445
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5.3 Problem Solving Practice Questions
159
88. The function f is de ned by f ( x )=x–10 for all
positive numbers x . if u =()ft for some positive
numbers t and u , what is t in terms of u ?
(A) 10u+
(B) 10 2
u
()
+
(C) 10
2
u+
(D)
(10)
2
u+
(E) (10)
22
u+
89. A glass was lled with 10 ounces of water, and
0.01 ounce of the water evaporated each day during a
20‐day period. What percent of the original amount of
water evaporated during this period?
(A) 0.002%
(B) 0.02%
(C) 0.2%
(D) 2%
(E) 20%
90. If m and p are positive integers and m2 + p2 < 100,
what is the greatest possible value of mp?
(A) 36
(B) 42
(C) 48
(D) 49
(E) 51
91. If and
x
y
c
d
d
c
b
a
==, which of the following must be true?
I.
y
x
b
a
=
II.
x
a
y
b
=
III.
y
a
x
b
=
(A) I only
(B) II only
(C) I and II only
(D) I and III only
(E) I, II, and III
92. If k is an integer and (0.0025)(0.025)(0.00025) × 10
k
is an integer, what is the least possible value of k ?
(A) –12
(B) –6
(C) 0
(D) 6
(E) 12
93. If a ( a + 2) = 24 and b ( b + 2) = 24, where a ≠ b , then
a + b =
(A) –48
(B) –2
(C) 2
(D) 46
(E) 48
94. In a recent election, Ms. Robbins received 8,000votes
cast by independent voters, that is, voters not
registered with a speci c political party. She also
received 10 percent of the votes cast by those voters
registered with a political party. If N is the total number
of votes cast in the election and 40 percent of the
votes cast were cast by independent voters, which of
the following represents the number of votes that
Ms. Robbins received?
(A) 0.06 N + 3,200
(B) 0.1 N + 7,200
(C) 0.4 N + 7,200
(D) 0.1 N + 8,000
(E) 0.06 N + 8,000
B
CA
95. In the gure shown, the triangle is inscribed in the
semicircle. If the length of line segment AB is 8 and
the length of line segment BC is 6, what is the length
of arc ABC ?
(A) 15π
(B) 12π
(C) 10π
(D) 7π
(E) 5π
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GMAT® Offi cial Guide 2018
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96. A manufacturer makes and sells 2products, P and Q.
The revenue from the sale of each unit of P is $20.00
and the revenue from the sale of each unit of Q is
$17.00. Last year the manufacturer sold twice as
many units of Q as P. What was the manufacturer’s
average (arithmetic mean) revenue per unit sold of
these 2products last year?
(A) $28.50
(B) $27.00
(C) $19.00
(D) $18.50
(E) $18.00
97. On a certain day, orangeade was made by mixing a
certain amount of orange juice with an equal amount
of water. On the next day, orangeade was made by
mixing the same amount of orange juice with twice
the amount of water. On both days, all the orangeade
that was made was sold. If the revenue from selling
the orangeade was the same for both days and if the
orangeade was sold at $0.60 per glass on the rst
day, what was the price per glass on the second day?
(A) $0.15
(B) $0.20
(C) $0.30
(D) $0.40
(E) $0.45
98. A worker carries jugs of liquid soap from a production
line to a packing area, carrying 4 jugs per trip. If the
jugs are packed into cartons that hold 7 jugs each,
how many jugs are needed to ll the last partially lled
carton after the worker has made 17 trips?
(A) 1
(B) 2
(C) 4
(D) 5
(E) 6
w
w
99. The gure shown above represents a modern painting
that consists of four differently colored rectangles,
each of which has length ℓ and width w . If the area of
the painting is 4,800 square inches, what is the width,
in inches, of each of the four rectangles?
(A) 15
(B) 20
(C) 25
(D) 30
(E) 40
100. A certain fruit stand sold apples for $0.70 each and
bananas for $0.50 each. If a customer purchased
both apples and bananas from the stand for a total of
$6.30, what total number of apples and bananas did
the customer purchase?
(A) 10
(B) 11
(C) 12
(D) 13
(E) 14
101. In the xy ‐plane, what is the slope of the line with
equation 3 x + 7 y = 9?
(A) 7
3
−
(B) 3
7
−
(C)
3
7
(D) 3
(E) 7
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5.3 Problem Solving Practice Questions
161
102. Working simultaneously and independently at an
identical constant rate, four machines of a certain type
can produce a total of x units of product P in 6days.
How many of these machines, working simultaneously
and independently at this constant rate, can produce a
total of 3 x units of productP in 4 days?
(A) 24
(B) 18
(C) 16
(D) 12
(E) 8
103. At a certain school, the ratio of the number of second
graders to the number of fourth graders is 8 to 5, and
the ratio of the number of rst graders to the number
of second graders is 3 to 4. If the ratio of the number
of third graders to the number of fourth graders is 3
to 2, what is the ratio of the number of rst graders to
the number of third graders?
(A) 16 to 15
(B) 9 to 5
(C) 5 to 16
(D) 5 to 4
(E) 4 to 5
104. The symbol Δ denotes one of the four arithmetic
operations: addition, subtraction, multiplication, or
division. If 6 Δ 3 ≤ 3, which of the following must be
true?
I. 2 Δ 2 = 0
II. 2 Δ 2 = 1
III. 4 Δ 2 = 2
(A) I only
(B) II only
(C) III only
(D) I and II only
(E) I, II, and III
105. The average distance between the Sun and a certain
planet is approximately 2.3 × 10
14 inches. Which
of the following is closest to the average distance
between the Sun and the planet, in kilometers?
(1 kilometer is approximately 3.9 × 10
4 inches.)
(A) 7.1 × 10
8
(B) 5.9 × 10
9
(C) 1.6 × 10
10
(D) 1.6 × 10
11
(E) 5.9 × 10
11
106. If mn ≠ 0 and 25 percent of n equals 371
2 percent
of m , what is the value of 12n
m?
(A) 18
(B)
32
3
(C) 8
(D) 3
(E) 9
8
107. In the coordinate plane, a circle has center (2,–3) and
passes through the point (5,0). What is the area of the
circle?
(A) 3
π
(B)
32
π
(C)
33
π
(D) 9
π
(E) 18
π
108. Last year Joe grew 1 inch and Sally grew 200percent
more than Joe grew. How many inches did Sally grow
last year?
(A) 0
(B) 1
(C) 2
(D) 3
(E) 4
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109. The cost C , in dollars, to remove p percent of a certain
pollutant from a pond is estimated by using the formula
C = 100,000
100
P
P−. According to this estimate, how
much more would it cost to remove 90 percent of the
pollutant from the pond than it would cost to remove
80 percent of the pollutant?
(A) $500,000
(B) $100,000
(C) $50,000
(D) $10,000
(E) $5,000
110. If xy ≠ 0 and x
2 y
2 – xy = 6, which of the following could
be y in terms of x ?
I.
1
2x
II.
2
x
−
III. 3
x
(A) I only
(B) II only
(C) I and II
(D) I and III
(E) II and III
111. At a certain instant in time, the number of cars, N ,
traveling on a portion of a certain highway can be
estimated by the formula
20
600 2
NLd
s
=+
where L is the number of lanes in the same direction,
d is the length of the portion of the highway, in feet,
and s is the average speed of the cars, in miles per
hour. Based on the formula, what is the estimated
number of cars traveling on a 1
2 ‐mile portion of
the highway if the highway has 2 lanes in the same
direction and the average speed of the cars is
40miles per hour? (5,280 feet = 1 mile)
(A) 155
(B) 96
(C) 80
(D) 48
(E) 24
112. 4.8 109
× is closest in value to
(A) 2,200
(B) 70,000
(C) 220,000
(D) 7,000,000
(E) 22,000,000
113. Three printing presses, R, S, and T, working together
at their respective constant rates, can do a certain
printing job in 4hours. SandT, working together at
their respective constant rates, can do the same job
in 5hours. How many hours would it take R, working
alone at its constant rate, to do the same job?
(A) 8
(B) 10
(C) 12
(D) 15
(E) 20
114. For a party, three solid cheese balls with diameters of
2 inches, 4 inches, and 6 inches, respectively, were
combined to form a single cheese ball. What was the
approximate diameter, in inches, of the new cheese
ball? (The volume of a sphere is 4
3,
3
r
π
where r is the
radius.)
(A) 12
(B) 16
(C) 16
3
(D)
38
3
(E)
236
3
115. The sum of all the integers k such that –26 < k < 24 is
(A) 0
(B) –2
(C) –25
(D) –49
(E) –51
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5.3 Problem Solving Practice Questions
163
TSR
0
116. The number line shown contains three points R , S ,
and T , whose coordinates have absolute values r , s ,
and t , respectively. Which of the following equals the
average (arithmetic mean) of the coordinates of the
points R , S , and T ?
(A)
s
(B) str+−
(C) 3
rst−−
(D) 3
rst++
(E) 3
str+−
117. Mark and Ann together were allocated n boxes of cookies
to sell for a club project. Mark sold 10 boxes less than n
and Ann sold 2boxes less than n . If Mark and Ann have
each sold at least one box of cookies, but together they
have sold less than n boxes, what is the value of n ?
(A) 11
(B) 12
(C) 13
(D) 14
(E) 15
118. A certain high school has 5,000 students. Of these
students, x are taking music, y are taking art, and
z are taking both music and art. How many students
are taking neither music nor art?
(A) 5,000 – z
(B) 5,000 – x – y
(C) 5,000 – x + z
(D) 5,000 – x – y – z
(E) 5,000 – x – y + z
119. Yesterday’s closing prices of 2,420 different stocks
listed on a certain stock exchange were all different
from today’s closing prices. The number of stocks that
closed at a higher price today than yesterday was
20 percent greater than the number that closed at a
lower price. How many of the stocks closed at a higher
price today than yesterday?
(A) 484
(B) 726
(C) 1,100
(D) 1,320
(E) 1,694
120. Each person who attended a company meeting was
either a stockholder in the company, an employee
of the company, or both. If 62 percent of those
who attended the meeting were stockholders and
47 percent were employees, what percent were
stockholders who were not employees?
(A) 34%
(B) 38%
(C) 45%
(D) 53%
(E) 62%
121. A gym class can be divided into 8 teams with an equal
number of players on each team or into 12 teams with
an equal number of players on each team. What is the
lowest possible number of students in the class?
(A) 20
(B) 24
(C) 36
(D) 48
(E) 96
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Accounts Amount Budgeted Amount Spent
Payroll $110,000 $117,000
Taxes 40,000 42,000
Insurance 2,500 2,340
122. The table shows the amount budgeted and the
amount spent for each of three accounts in a certain
company. For which of these accounts did the amount
spent differ from the amount budgeted by more than
6percent of the amount budgeted?
(A) Payroll only
(B) Taxes only
(C) Insurance only
(D) Payroll and Insurance
(E) Taxes and Insurance
B
C
P
A
123. In the gure above, triangle ABC is equilateral, and
point P is equidistant from vertices A , B , and C . If
triangle ABC is rotated clockwise about point P , what
is the minimum number of degrees the triangle must
be rotated so that point B will be in the position where
point A is now?
(A) 60
(B) 120
(C) 180
(D) 240
(E) 270
124. At least 2
3 of the 40 members of a committee must
vote in favor of a resolution for it to pass. What is the
greatest number of members who could vote against
the resolution and still have it pass?
(A) 19
(B) 17
(C) 16
(D) 14
(E) 13
1
0
2
4
6
8
10
12
14
16
18
20
number of computers assembled
234
day
56
125. The graph shows the number of computers assembled
during each of 6consecutive days. From what day to
the next day was the percent change in the number of
computers assembled the greatest in magnitude?
(A) From Day1 to Day2
(B) From Day2 to Day3
(C) From Day3 to Day4
(D) From Day4 to Day5
(E) From Day5 to Day6
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5.3 Problem Solving Practice Questions
165
126. If n = 20! + 17, then n is divisible by which of the
following?
I. 15
II. 17
III. 19
(A) None
(B) I only
(C) II only
(D) I and II
(E) II and III
127. The product of two negative numbers is 160. If the
lesser of the two numbers is 4 less than twice the
greater, what is the greater number?
(A) –20
(B) –16
(C) –10
(D) –8
(E) –4
128. According to a certain estimate, the depth N ( t ), in
centimeters, of the water in a certain tank at
t hours past 2:00 in the morning is given by
N ( t ) = –20( t – 5)
2 + 500 for 0 ≤ t ≤ 10. According to
this estimate, at what time in the morning does the
depth of the water in the tank reach its maximum?
(A) 5:30
(B) 7:00
(C) 7:30
(D) 8:00
(E) 9:00
129. After driving to a riverfront parking lot, Bob plans to
run south along the river, turn around, and return to
the parking lot, running north along the same path.
After running 3.25miles south, he decides to run for
only 50minutes more. If Bob runs at a constant rate of
8minutes per mile, how many miles farther south can
he run and still be able to return to the parking lot in
50minutes?
(A) 1.5
(B) 2.25
(C) 3.0
(D) 3.25
(E) 4.75
130. Alex deposited x dollars into a new account that earned
8 percent annual interest, compounded annually. One
year later Alex deposited an additional x dollars into the
account. If there were no other transactions and if the
account contained w dollars at the end of two years,
which of the following expresses x in terms of w ?
(A) 11.08
w
+
(B) 1.08 1.16
w
+
(C) 1.16 1.24
w
+
(D) 1.08 (1.08)2
w
+
(E) (1.08) (1.08)
23
w
+
131. M is the sum of the reciprocals of the consecutive
integers from 201 to 300, inclusive. Which of the
following is true?
(A)
1
3
1
2
M<<
(B)
1
5
1
3
M<<
(C)
1
7
1
5
M<<
(D)
1
9
1
7
M<<
(E) 1
12
1
9
M<<
132. Working simultaneously at their respective constant
rates, Machines A and B produce 800 nails in x hours.
Working alone at its constant rate, Machine A produces
800 nails in y hours. In terms of x and y , how many
hours does it take Machine B, working alone at its
constant rate, to produce 800 nails?
(A) x
xy+
(B) y
xy+
(C) xy
xy+
(D) xy
xy−
(E) xy
yx−
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GMAT® Offi cial Guide 2018
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133. In the Johnsons’ monthly budget, the dollar
amounts allocated to household expenses, food,
and miscellaneous items are in the ratio 5:2:1,
respectively. If the total amount allocated to these
three categories is $1,800, what is the amount
allocated to food?
(A) $900
(B) $720
(C) $675
(D) $450
(E) $225
Number of
Marbles in
Each of Three
Bags
Percent of Marbles
in Each Bag That Are
Blue (to the nearest
tenth)
Bag P 37 10.8%
Bag Q x 66.7%
Bag R 32 50.0%
134. If 1
3 of the total number of marbles in the three bags
listed in the table above are blue, how many marbles
are there in bag Q ?
(A) 5
(B) 9
(C) 12
(D) 23
(E) 46
135. (0.0036)(2.8)
(0.04)(0.1)(0.003) =
(A) 840.0
(B) 84.0
(C) 8.4
(D) 0.84
(E) 0.084
136. If n is an integer greater than 6, which of the following
must be divisible by 3?
(A) n ( n + 1)( n – 4)
(B) n ( n + 2)( n – 1)
(C) n ( n + 3)( n – 5)
(D) n ( n + 4)( n – 2)
(E) n ( n + 5)( n – 6)
Age Category
(in years)
Number of
Employees
Less than 20 29
20–29 58
30–39 36
40–49 21
50–59 10
60–69 5
70 and over 2
137. The table above gives the age categories of the
161employees at Company X and the number of
employees in each category. According to the table,
if m is the median age, in years, of the employees
at CompanyX, then m must satisfy which of the
following?
(A) 20 ≤ m ≤ 29
(B) 25 ≤ m ≤ 34
(C) 30 ≤ m ≤ 39
(D) 35 ≤ m ≤ 44
(E) 40 ≤ m ≤ 49
138 . If x and y are positive numbers such that x + y = 1,
which of the following could be the value of
100 x + 200 y ?
I. 80
II. 140
III. 199
(A) II only
(B) III only
(C) I and II
(D) I and III
(E) II and III
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5.3 Problem Solving Practice Questions
167
139. If X is the hundredths digit in the decimal 0.1X and if
Y is the thousandths digit in the decimal 0.02Y, where
X and Y are nonzero digits, which of the following is
closest to the greatest possible value of X
Y
0.1
0.02 ?
(A) 4
(B) 5
(C) 6
(D) 9
(E) 10
140. Clarissa will create her summer reading list by
randomly choosing 4books from the 10books
approved for summer reading. She will list the books in
the order in which they are chosen. How many different
lists are possible?
(A) 6
(B) 40
(C) 210
(D) 5,040
(E) 151,200
141 . If n is a positive integer and the product of all the
integers from 1 to n , inclusive, is divisible by 990,
what is the least possible value of n ?
(A) 8
(B) 9
(C) 10
(D) 11
(E) 12
142 . The probability that event M will not occur is 0.8 and the
probability that event R will not occur is 0.6. If events M
and R cannot both occur, which of the following is the
probability that either event M or event R will occur?
(A)
1
5
(B)
2
5
(C)
3
5
(D)
4
5
(E)
12
25
143 . The total cost for Company X to produce a batch of
tools is $10,000 plus $3 per tool. Each tool sells for $8.
The gross pro t earned from producing and selling
these tools is the total income from sales minus the
total production cost. If a batch of 20,000 tools is
produced and sold, then Company X’s gross pro t
per tool is
(A) $3.00
(B) $3.75
(C) $4.50
(D) $5.00
(E) $5.50
144 . If Q is an odd number and the median of Q consecutive
integers is 120, what is the largest of these integers?
(A) 1
2120
Q−+
(B)
2119
Q+
(C)
2120
Q+
(D) 119
2
Q+
(E) 120
2
Q+
145 . A ladder of a re truck is elevated to an angle of 60°
and extended to a length of 70 feet. If the base of
the ladder is 7 feet above the ground, how many feet
above the ground does the ladder reach?
(A) 35
(B) 42
(C)
35 3
(D)
7353+
(E)
7423+
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GMAT® Offi cial Guide 2018
168
4 ft
10 ft
146. The window in the gure above consists of a rectangle
and a semicircle with dimensions as shown. What is
the area, in square feet, of the window?
(A) 40 + 8π
(B) 40 + 2π
(C) 32 + 8π
(D) 32 + 4π
(E) 32 + 2π
147. If there are fewer than 8 zeros between the decimal
point and the rst nonzero digit in the decimal
expansion of t
1,000
4
⎛
⎝
⎜⎞
⎠
⎟, which of the following numbers
could be the value of t ?
I. 3
II. 5
III. 9
(A) None
(B) I only
(C) II only
(D) III only
(E) II and III
148. A three‐digit code for certain locks uses the digits
0, 1, 2, 3, 4, 5, 6, 7, 8, 9 according to the following
constraints. The rst digit cannot be 0 or 1, the
second digit must be 0 or 1, and the second and third
digits cannot both be 0 in the same code. How many
different codes are possible?
(A) 144
(B) 152
(C) 160
(D) 168
(E) 176
149. Jackie has two solutions that are 2 percent sulfuric
acid and 12 percent sulfuric acid by volume,
respectively. If these solutions are mixed in appropriate
quantities to produce 60 liters of a solution that is
5percent sulfuric acid, approximately how many liters
of the 2 percent solution will be required?
(A) 18
(B) 20
(C) 24
(D) 36
(E) 42
150. If Jake loses 8 pounds, he will weigh twice as much as
his sister. Together they now weigh 278 pounds. What
is Jake’s present weight, in pounds?
(A) 131
(B) 135
(C) 139
(D) 147
(E) 188
151. For each student in a certain class, a teacher adjusted
the student’s test score using the formula y=0.8x+20,
where x is the student’s original test score and y is the
student’s adjusted test score. If the standard deviation of
the original test scores of the students in the class was
20, what was the standard deviation of the adjusted test
scores of the students in the class?
(A) 12
(B) 16
(C) 28
(D) 36
(E) 40
152. Last year 26 members of a certain club traveled
to England, 26 members traveled to France, and
32members traveled to Italy. Last year no members
of the club traveled to both England and France,
6members traveled to both England and Italy, and
11members traveled to both France and Italy. How
many members of the club traveled to at least one of
these three countries last year?
(A) 52
(B) 67
(C) 71
(D) 73
(E) 79
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5.3 Problem Solving Practice Questions
169
153. A store reported total sales of $385 million for
February of this year. If the total sales for the same
month last year was $320 million, approximately what
was the percent increase in sales?
(A) 2%
(B) 17%
(C) 20%
(D) 65%
(E) 83%
154. When positive integer x is divided by positive integer y,
the remainder is 9. If 96.12,
x
y= what is the value
of y ?
(A) 96
(B) 75
(C) 48
(D) 25
(E) 12
155. If x (2 x +1)=0 and 1
2
x+⎞
⎠
⎟
⎛
⎝
⎜(2 x –3)=0, then x =
(A) 3−
(B) 1
2
−
(C) 0
(D)
1
2
(E) 3
2
XY
156. Figures X and Y above show how eight identical
triangular pieces of cardboard were used to form a
square and a rectangle, respectively. What is the ratio
of the perimeter of X to the perimeter of Y ?
(A) 2:3
(B) 2:2
(C) 22:3
(D)
1:1
(E) 2:1
157. A certain experimental mathematics program was tried
out in 2 classes in each of 32 elementary schools
and involved 37teachers. Each of the classes had
1teacher and each of the teachers taught at least 1,
but not more than 3, of the classes. If the number of
teachers who taught 3 classes is n , then the least and
greatest possible values of n , respectively, are
(A) 0 and 13
(B) 0 and 14
(C) 1 and 10
(D) 1 and 9
(E) 2 and 8
158. For the positive numbers, n , n + 1, n + 2, n + 4, and
n + 8, the mean is how much greater than the median?
(A) 0
(B) 1
(C) n + 1
(D) n + 2
(E) n + 3
159. The interior of a rectangular carton is designed by a
certain manufacturer to have a volume of x cubic feet
and a ratio of length to width to height of 3:2:2. In
terms of x , which of the following equals the height of
the carton, in feet?
(A)
3x
(B) 2
3
3x
(C) 3
2
3x
(D)
2
3
3x
(E)
3
2
3x
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GMAT® Offi cial Guide 2018
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160. The present ratio of students to teachers at a certain
school is 30 to 1. If the student enrollment were to
increase by 50 students and the number of teachers
were to increase by 5, the ratio of students to
teachers would then be 25 to 1. What is the present
number of teachers?
(A) 5
(B) 8
(C) 10
(D) 12
(E) 15
161. What is the smallest integer n for which 25
n > 5
12 ?
(A) 6
(B) 7
(C) 8
(D) 9
(E) 10
162. Sixty percent of the members of a study group are
women, and 45percent of those women are lawyers.
If one member of the study group is to be selected
at random, what is the probability that the member
selected is a woman lawyer?
(A) 0.10
(B) 0.15
(C) 0.27
(D) 0.33
(E) 0.45
163. Each year for 4 years, a farmer increased the number
of trees in a certain orchard by 1
4 of the number of
trees in the orchard the preceding year. If all of the
trees thrived and there were 6,250 trees in the orchard
at the end of the 4‐year period, how many trees were
in the orchard at the beginning of the 4‐year period?
(A) 1,250
(B) 1,563
(C) 2,250
(D) 2,560
(E) 2,752
400,000
300,000
200,000
100,000
0
number of shipments
1990 1992 1994 1996 1998 2000
year
Number of Shipments of Manufactured Homes
in the United States, 1990–2000
164. According to the chart shown, which of the following is
closest to the median annual number of shipments of
manufactured homes in the United States for the years
from 1990 to 2000, inclusive?
(A) 250,000
(B) 280,000
(C) 310,000
(D) 325,000
(E) 340,000
165. For the positive integers a , b , and k , ab
k means that
ak is a divisor of b , but 1
ak+ is not a divisor of b . If k is
a positive integer and 272,
k then k is equal to
(A) 2
(B) 3
(C) 4
(D) 8
(E) 18
166. A certain characteristic in a large population has a
distribution that is symmetric about the mean m .
If 68 percent of the distribution lies within one
standard deviation d of the mean, what percent of the
distribution is less than m + d ?
(A) 16%
(B) 32%
(C) 48%
(D) 84%
(E) 92%
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5.3 Problem Solving Practice Questions
171
167. Four extra‐large sandwiches of exactly the same size
were ordered for m students, where m > 4. Three
of the sandwiches were evenly divided among the
students. Since 4 students did not want any of the
fourth sandwich, it was evenly divided among the
remaining students. If Carol ate one piece from each
of the four sandwiches, the amount of sandwich that
she ate would be what fraction of a whole extra‐large
sandwich?
(A) 4
(4)
m
mm
+
−
(B) 24
(4)
m
mm
−
−
(C) 44
(4)
m
mm
−
−
(D) 48
(4)
m
mm
−
−
(E) 412
(4)
m
mm
−
−
168. Which of the following equations has 1 + 2 as one of
its roots?
(A) x
2 + 2 x – 1 = 0
(B) x
2 – 2 x + 1 = 0
(C) x
2 + 2 x + 1 = 0
(D) x
2 – 2 x – 1 = 0
(E) x
2 – x – 1 = 0
169. In Country C, the unemployment rate among
construction workers dropped from 16 percent on
September 1, 1992, to 9 percent on September 1,
1996. If the number of construction workers was
20 percent greater on September 1, 1996, than
on September 1, 1992, what was the approximate
percent change in the number of unemployed
construction workers over this period?
(A) 50% decrease
(B) 30% decrease
(C) 15% decrease
(D) 30% increase
(E) 55% increase
170. In a box of 12 pens, a total of 3 are defective. If a
customer buys 2 pens selected at random from the
box, what is the probability that neither pen will be
defective?
(A)
1
6
(B)
2
9
(C) 6
11
(D) 9
16
(E)
3
4
171. At a certain fruit stand, the price of each apple is
40 cents and the price of each orange is 60 cents.
Mary selects a total of 10 apples and oranges from the
fruit stand, and the average (arithmetic mean) price of
the 10 pieces of fruit is 56 cents. How many oranges
must Mary put back so that the average price of the
pieces of fruit that she keeps is 52 cents?
(A) 1
(B) 2
(C) 3
(D) 4
(E) 5
172. A pharmaceutical company received $3 million in
royalties on the rst $20million in sales of the generic
equivalent of one of its products and then $9 million
in royalties on the next $108 million in sales. By
approximately what percent did the ratio of royalties to
sales decrease from the rst $20million in sales to the
next $108 million in sales?
(A) 8%
(B) 15%
(C) 45%
(D) 52%
(E) 56%
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GMAT® Offi cial Guide 2018
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Times at Which the Door
Opened from 8:00 to 10:00
8:00 8:06 8:30 9:05
8:03 8:10 8:31 9:11
8:04 8:18 8:54 9:29
8:04 8:19 8:57 9:31
173. The light in a restroom operates with a 15-minute timer
that is reset every time the door opens as a person
goes in or out of the room. Thus, after someone
enters or exits the room, the light remains on for only
15 minutes unless the door opens again and resets the
timer for another 15 minutes. If the times listed above
are the times at which the door opened from 8:00 to
10:00, approximately how many minutes during this
two-hour period was the light off?
(A) 10
(B) 25
(C) 35
(D) 40
(E) 70
60°
174. The parallelogram shown has four sides of equal
length. What is the ratio of the length of the shorter
diagonal to the length of the longer diagonal?
(A)
1
2
(B) 1
2
(C) 1
22
(D) 1
3
(E) 1
23
175. If p is the product of the integers from 1 to 30,
inclusive, what is the greatest integer k for which
3k is a factor of p ?
(A) 10
(B) 12
(C) 14
(D) 16
(E) 18
176. If n = 3
8 – 2
8 , which of the following is NOT a factor
of n ?
(A) 97
(B) 65
(C) 35
(D) 13
(E) 5
177. In the gure shown, if the area of the shaded region is
3 times the area of the smaller circular region, then the
circumference of the larger circle is how many times
the circumference of the smaller circle?
(A) 4
(B) 3
(C) 2
(D) 3
(E) 2
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5.3 Problem Solving Practice Questions
173
178. Club X has more than 10 but fewer than 40 members.
Sometimes the members sit at tables with 3 members
at one table and 4 members at each of the other tables,
and sometimes they sit at tables with 3 members at
one table and 5 members at each of the other tables.
If they sit at tables with 6 members at each table
except one and fewer than 6 members at that one
table, how many members will be at the table that has
fewer than 6 members?
(A) 1
(B) 2
(C) 3
(D) 4
(E) 5
179. In order to complete a reading assignment on time,
Terry planned to read 90pages per day. However,
she read only 75 pages per day at rst, leaving
690pages to be read during the last 6 days before the
assignment was to be completed. How many days in
all did Terry have to complete the assignment on time?
(A) 15
(B) 16
(C) 25
(D) 40
(E) 46
180. If s >0 and r
s= s , what is r in terms of s ?
(A)
1
s
(B) s
(C)
ss
(D) 3
s
(E) 2
ss−
181. If 3 < x < 100, for how many values of x is 3
x the
square of a prime number?
(A) Two
(B) Three
(C) Four
(D) Five
(E) Nine
182. A researcher plans to identify each participant in a
certain medical experiment with a code consisting of
either a single letter or a pair of distinct letters written
in alphabetical order. What is the least number of
letters that can be used if there are 12 participants,
and each participant is to receive a different code?
(A) 4
(B) 5
(C) 6
(D) 7
(E) 8
y
x
O1
1
2
183. The graph of which of the following equations is a
straight line that is parallel to line ℓ in the gure above?
(A) 3 y – 2 x = 0
(B) 3 y + 2 x = 0
(C) 3 y + 2 x = 6
(D) 2 y – 3 x = 6
(E) 2 y + 3 x = –6
184. An object thrown directly upward is at a height of h feet
after t seconds, where h = –16( t – 3)
2 + 150. At what
height, in feet, is the object 2 seconds after it reaches
its maximum height?
(A) 6
(B) 86
(C) 134
(D) 150
(E) 166
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185. Which of the following is equivalent to the pair of
inequalities x + 6 > 10 and x – 3 ≤ 5?
(A) 2 ≤ x < 16
(B) 2 ≤ x < 4
(C) 2 < x ≤ 8
(D) 4 < x ≤ 8
(E) 4 ≤ x < 16
186. David has d books, which is 3 times as many as Jeff
and 1
2 as many as Paula. How many books do the
three of them have altogether, in terms of d ?
(A)
5
6d
(B)
7
3d
(C)
10
3d
(D)
7
2d
(E)
9
2d
187. There are 8 teams in a certain league and each team
plays each of the other teams exactly once. If each
game is played by 2 teams, what is the total number of
games played?
(A) 15
(B) 16
(C) 28
(D) 56
(E) 64
188. At his regular hourly rate, Don had estimated the labor
cost of a repair job as $336 and he was paid that
amount. However, the job took 4 hours longer than
he had estimated and, consequently, he earned
$2 per hour less than his regular hourly rate. What was
the time Don had estimated for the job, in hours?
(A) 28
(B) 24
(C) 16
(D) 14
(E) 12
189. If p
q < 1, and p and q are positive integers, which of
the following must be greater than 1?
(A) p
q
(B) 2
p
q
(C)
2
p
q
(D) 2
q
p
(E)
q
p
190. To mail a package, the rate is x cents for the rst
pound and y cents for each additional pound, where
x > y . Two packages weighing 3 pounds and 5pounds,
respectively, can be mailed separately or combined as
one package. Which method is cheaper, and how much
money is saved?
(A) Combined, with a savings of x – y cents
(B) Combined, with a savings of y – x cents
(C) Combined, with a savings of x cents
(D) Separately, with a savings of x – y cents
(E) Separately, with a savings of y cents
191. If money is invested at r percent interest, compounded
annually, the amount of the investment will double
in approximately 70
r years. If Pat’s parents invested
$5,000 in a long‐term bond that pays 8 percent
interest, compounded annually, what will be the
approximate total amount of the investment 18years
later, when Pat is ready for college?
(A) $20,000
(B) $15,000
(C) $12,000
(D) $10,000
(E) $9,000
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5.3 Problem Solving Practice Questions
175
192. On a recent trip, Cindy drove her car 290 miles,
rounded to the nearest 10miles, and used 12 gallons
of gasoline, rounded to the nearest gallon. The actual
number of miles per gallon that Cindy’s car got on this
trip must have been between
(A) 290
12.5 and 290
11.5
(B)
295
12 and 285
11.5
(C)
285
12 and 295
12
(D) 285
12.5 and 295
11.5
(E) 295
12.5 and 285
11.5
x
12 34–1–2–4–5 –3 5
0
193. Which of the following inequalities is an algebraic
expression for the shaded part of the number line
above?
(A) | x | ≤ 3
(B) | x | ≤ 5
(C) | x – 2 | ≤ 3
(D) | x – 1 | ≤ 4
(E) | x + 1 | ≤ 4
194. In a small snack shop, the average (arithmetic mean)
revenue was $400 per day over a 10‐day period.
During this period, if the average daily revenue was
$360 for the rst 6 days, what was the average daily
revenue for the last 4days?
(A) $420
(B) $440
(C) $450
(D) $460
(E) $480
195. If y is the smallest positive integer such that
3,150 multiplied by y is the square of an integer,
then y must be
(A) 2
(B) 5
(C) 6
(D) 7
(E) 14
196. If [ x ] is the greatest integer less than or equal to x ,
what is the value of [–1.6] + [3.4] + [2.7]?
(A) 3
(B) 4
(C) 5
(D) 6
(E) 7
197. In the rst week of the year, Nancy saved $1. In each
of the next 51weeks, she saved $1 more than she
had saved in the previous week. What was the total
amount that Nancy saved during the 52 weeks?
(A) $1,326
(B) $1,352
(C) $1,378
(D) $2,652
(E) $2,756
198. In a certain sequence, the term xn is given by the
formula 21
2()
12
xx x
nn n
=−
−− for all 2n≥. If 3
0
x=
and x
1 = 2, what is the value of 3
x?
(A) 2.5
(B) 3.125
(C) 4
(D) 5
(E) 6.75
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199. During a trip, Francine traveled x percent of the total
distance at an average speed of 40 miles per hour
and the rest of the distance at an average speed of
60 miles per hour. In terms of x , what was Francine’s
average speed for the entire trip?
(A)
180
2
x−
(B) 60
4
x+
(C)
300
5
x−
(D) 600
115 x−
(E)
12,000
200x+
200. If n = (33)
43 + (43)
33 , what is the units digit of n ?
(A) 0
(B) 2
(C) 4
(D) 6
(E) 8
201. TeamA and TeamB are competing against each other
in a game of tug-of-war. TeamA, consisting of 3males
and 3females, decides to line up male, female, male,
female, male, female. The lineup that TeamA chooses
will be one of how many different possible lineups?
(A) 9
(B) 12
(C) 15
(D) 36
(E) 720
202. A border of uniform width is placed around a
rectangular photograph that measures 8 inches by
10inches. If the area of the border is 144 square
inches, what is the width of the border, in inches?
(A) 3
(B) 4
(C) 6
(D) 8
(E) 9
203. If 1
25
37
d=× is expressed as a terminating decimal,
how many nonzero digits will d have?
(A) One
(B) Two
(C) Three
(D) Seven
(E) Ten
204. For any positive integer n , the sum of the rst
n positive integers equals (1)
2
nn+. What is the sum of
all the even integers between 99 and 301?
(A) 10,100
(B) 20,200
(C) 22,650
(D) 40,200
(E) 45,150
205. How many prime numbers between 1 and 100 are
factors of 7,150?
(A) One
(B) Two
(C) Three
(D) Four
(E) Five
206. A sequence of numbers a
1 , a
2 , a
3 , . . . is de ned as
follows: a
1 = 3, a
2 = 5, and every term in the sequence
after a
2 is the product of all terms in the sequence
preceding it, e.g., a
3 = ( a
1 )( a
2 ) and a
4 =( a
1 )( a
2 )( a
3 ).
If a
n = t and n > 2, what is the value of a
n + 2 in terms
of t ?
(A) 4 t
(B) t
2
(C) t
3
(D) t
4
(E) t
8
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5.3 Problem Solving Practice Questions
177
207. Last year the price per share of Stock X increased
by k percent and the earnings per share of Stock X
increased by m percent, where k is greater than m .
By what percent did the ratio of price per share to
earnings per share increase, in terms of k and m ?
(A) %
k
m
(B) ( k – m )%
(C)
100( )
100 %
km
k
−
+
(D)
100( )
100 %
km
m
−
+
(E) 100( )
100 %
km
km
−
++
208. Of the 300 subjects who participated in an experiment
using virtual‐reality therapy to reduce their fear of
heights, 40 percent experienced sweaty palms,
30 percent experienced vomiting, and 75percent
experienced dizziness. If all of the subjects
experienced at least one of these effects and
35percent of the subjects experienced exactly two of
these effects, how many of the subjects experienced
only one of these effects?
(A) 105
(B) 125
(C) 130
(D) 180
(E) 195
209. If 1
3
1
m=−
−, then 2
m− is equal to
(A) 9−
(B) 3−
(C) 1
9
−
(D) 1
9
(E) 9
210. A photography dealer ordered 60 Model X cameras to
be sold for $250 each, which represents a 20percent
markup over the dealer’s initial cost for each camera.
Of the cameras ordered, 6 were never sold and
were returned to the manufacturer for a refund of
50 percent of the dealer’s initial cost. What was the
dealer’s approximate pro t or loss as a percent of the
dealer’s initial cost for the 60 cameras?
(A) 7% loss
(B) 13% loss
(C) 7% pro t
(D) 13% pro t
(E) 15% pro t
211. Seven pieces of rope have an average (arithmetic
mean) length of 68centimeters and a median length of
84centimeters. If the length of the longest piece of rope
is 14 centimeters more than 4 times the length of the
shortest piece of rope, what is the maximum possible
length, in centimeters, of the longest piece of rope?
(A) 82
(B) 118
(C) 120
(D) 134
(E) 152
212. What is the difference between the sixth and the fth
terms of the sequence 2, 4, 7, … whose n th term is
21
nn
+−?
(A) 2
(B) 3
(C) 6
(D) 16
(E) 17
213. From the consecutive integers –10 to 10, inclusive,
20integers are randomly chosen with repetitions
allowed. What is the least possible value of the product
of the 20 integers?
(A) (10)
20
−
(B) (10)
10
−
(C) 0
(D) (10)19
−
(E) (10)20
−
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GMAT® Offi cial Guide 2018
178
214. The letters D, G, I, I, and T can be used to form 5‐letter
strings such as DIGIT or DGIIT. Using these letters, how
many 5‐letter strings can be formed in which the two
occurrences of the letter I are separated by at least
one other letter?
(A) 12
(B) 18
(C) 24
(D) 36
(E) 48
215. Last Sunday a certain store sold copies of Newspaper A
for $1.00 each and copies of Newspaper B for $1.25
each, and the store sold no other newspapers that
day. If r percent of the store’s revenue from newspaper
sales was from Newspaper A and if p percent of
the newspapers that the store sold were copies of
Newspaper A, which of the following expresses r in
terms of p ?
(A) 100
125
p
p−
(B) 150
250
p
p−
(C) 300
375
p
p−
(D) 400
500
p
p−
(E) 500
625
p
p−
216.
0.99999999
1.0001
0.99999991
1.0003
−=
(A) 10 8−
(B) 3(10 )
8−
(C) 3(10 )
4−
(D) 2(10 )
4−
(E) 10 4−
217. For the past n days, the average (arithmetic mean)
daily production at a company was 50 units. If today’s
production of 90 units raises the average to 55 units
per day, what is the value of n ?
(A) 30
(B) 18
(C) 10
(D) 9
(E) 7
O1
y
x
1
218. In the coordinate system above, which of the following
is the equation of line?
(A) 23 6xy−=
(B) 23 6xy+=
(C) 32 6xy+=
(D) 23 6xy−=−
(E) 32 6xy−=−
219. If a two‐digit positive integer has its digits reversed,
the resulting integer differs from the original by 27. By
how much do the two digits differ?
(A) 3
(B) 4
(C) 5
(D) 6
(E) 7
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5.3 Problem Solving Practice Questions
179
220. In an electric circuit, two resistors with resistances x
and y are connected in parallel. In this case, if r is the
combined resistance of these two resistors, then the
reciprocal of r is equal to the sum of the reciprocals of
x and y . What is r in terms of x and y ?
(A) xy
(B) xy+
(C) 1
xy+
(D) xy
xy+
(E)
xy
xy
+
221. Xavier, Yvonne, and Zelda each try independently to
solve a problem. If their individual probabilities for
success are 1
4, 1
2, and 5
8, respectively, what is the
probability that Xavier and Yvonne, but not Zelda, will
solve the problem?
(A)
11
8
(B)
7
8
(C) 9
64
(D) 5
64
(E) 3
64
222. If 11
1
1
4xx x
−+=+, then x could be
(A) 0
(B) –1
(C) –2
(D) –3
(E) –4
223. 1
2
1
4
1
16
32 1
⎛
⎝
⎜⎞
⎠
⎟⎛
⎝
⎜⎞
⎠
⎟⎛
⎝
⎜⎞
⎠
⎟
−− −
(A) 1
2
48
⎛
⎝
⎜⎞
⎠
⎟
−
(B) 1
2
11
⎛
⎝
⎜⎞
⎠
⎟
−
(C) 1
2
6
⎛
⎝
⎜⎞
⎠
⎟
−
(D) 1
8
11
⎛
⎝
⎜⎞
⎠
⎟
−
(E) 1
8
6
⎛
⎝
⎜⎞
⎠
⎟
−
a°
224. The gure shown above consists of a shaded 9-sided
polygon and 9unshaded isosceles triangles. For each
isosceles triangle, the longest side is a side of the
shaded polygon and the two sides of equal length are
extensions of the two adjacent sides of the shaded
polygon. What is the value of a?
(A) 100
(B) 105
(C) 110
(D) 115
(E) 120
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GMAT® Offi cial Guide 2018
180
225. List T consists of 30 positive decimals, none of which
is an integer, and the sum of the 30 decimals is S . The
estimated sum of the 30 decimals, E , is de ned as
follows. Each decimal in T whose tenths digit is even
is rounded up to the nearest integer, and each decimal
in T whose tenths digit is odd is rounded down to the
nearest integer; E is the sum of the resulting integers.
If 1
3 of the decimals in T have a tenths digit that is
even, which of the following is a possible value of
E – S ?
I. –16
II. 6
III. 10
(A) I only
(B) I and II only
(C) I and III only
(D) II and III only
(E) I, II, and III
226. If 56
xx−=, then x has how many possible values?
(A) None
(B) One
(C) Two
(D) A nite number greater than two
(E) An in nite number
227. Seed mixture X is 40 percent ryegrass and 60 percent
bluegrass by weight; seed mixture Y is 25 percent
ryegrass and 75 percent fescue. If a mixture of X and
Y contains 30 percent ryegrass, what percent of the
weight of the mixture is X?
(A) 10%
(B)
33 1
3%
(C) 40%
(D) 50%
(E)
66 2
3%
228. How many of the integers that satisfy the inequality
(2)(3)
2
xx
x
++
−≥0 are less than 5?
(A) 1
(B) 2
(C) 3
(D) 4
(E) 5
229. Of the 150 houses in a certain development,
60percent have air-conditioning, 50percent have a
sunporch, and 30percent have a swimming pool. If
5of the houses have all three of these amenities and
5have none of them, how many of the houses have
exactly two of these amenities?
(A) 10
(B) 45
(C) 50
(D) 55
(E) 65
230. The value of 2222
5
14 15 16 17
+++
−−−−
is how many
times the value of 2(17)−?
(A)
3
2
(B)
5
2
(C) 3
(D) 4
(E) 5
181
5.4 Problem Solving Answer Key
5.4 Answer Key
1. E
2. D
3. E
4. A
5. B
6. E
7. C
8. D
9. C
10. E
11. A
12. C
13. B
14. B
15. D
16. E
17. A
18. B
19. D
20. B
21. C
22. D
23. E
24. C
25. C
26. C
27. E
28. D
29. B
30. C
31. C
32. D
33. C
34. A
35. B
36. E
37. E
38. D
39. C
40. E
41. E
42. D
43. D
44. B
45. D
46. D
47. C
48. E
49. B
50. E
51. D
52. B
53. A
54. E
55. D
56. D
57. D
58. B
59. A
60. E
61. A
62. C
63. B
64. C
65. B
66. A
67. B
68. B
69. B
70. D
71. D
72. C
73. E
74. E
75. D
76. B
77. B
78. C
79. B
80. D
81. A
82. D
83. D
84. D
85. E
86. D
87. B
88. D
89. D
90. D
91. C
92. E
93. B
94. E
95. E
96. E
97. D
98. B
99. B
100. B
101. B
102. B
103. E
104. C
105. B
106. A
107. E
108. D
109. A
110. E
111. D
112. B
113. E
114. E
115. D
116. E
117. A
118. E
119. D
120. D
GMAT® Offi cial Guide 2018
182
121. B
122. D
123. D
124. E
125. D
126. C
127. D
128. B
129. A
130. D
131. A
132. E
133. D
134. B
135. A
136. A
137. A
138. E
139. D
140. D
141. D
142. C
143. C
144. A
145. D
146. E
147. A
148. B
149. E
150. E
151. B
152. B
153. C
154. B
155. B
156. C
157. A
158. B
159. B
160. E
161. B
162. C
163. D
164. C
165. B
166. D
167. E
168. D
169. B
170. C
171. E
172. C
173. B
174. D
175. C
176. C
177. C
178. E
179. B
180. D
181. B
182. B
183. A
184. B
185. D
186. C
187. C
188. B
189. E
190. A
191. A
192. D
193. E
194. D
195. E
196. A
197. C
198. C
199. E
200. A
201. D
202. A
203. B
204. B
205. D
206. D
207. D
208. D
209. D
210. D
211. D
212. E
213. E
214. D
215. D
216. D
217. E
218. B
219. A
220. D
221. E
222. C
223. B
224. A
225. B
226. C
227. B
228. D
229. D
230. C
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183
5.5 Problem Solving Answer Explanations
1. The price of a coat in a certain store is $500. If the
price of the coat is to be reduced by $150, by what
percent is the price to be reduced?
(A) 10%
(B) 15%
(C) 20%
(D) 25%
(E) 30%
Arithmetic Percents
A reduction of $150 from $500 represents a
percent decrease of 150
500 100 % 30%×
⎛
⎝
⎜⎞
⎠
⎟=.
erefore, the price of the coat was reduced
by 30%.
e correct answer is E.
2. On a vacation, Rose exchanged $500.00 for euros
at an exchange rate of 0.80euro per dollar and
spent 3
4 of the euros she received. If she exchanged
the remaining euros for dollars at an exchange rate
of $1.20per euro, what was the dollar amount she
received?
(A) $60.00
(B) $80.00
(C) $100.00
(D) $120.00
(E) $140.00
Arithmetic Operations with rational numbers
At the exchange rate of 0.80 euro per dollar,
Rose exchanged $500.00 for (0.80)(500)=
400euros. She spent 3
4(400)=300euros, had
400–300=100euros left, and exchanged them
for dollars at the exchange rate of $1.20 per euro.
erefore, the dollar amount she received was
(1.20)(100)=$120.00.
e correct answer is D.
x
v
x
x
x
x
y
y
y
w
v
w
3. Each of the 12 squares shown is labeled x, y, v, or
w. What is the ratio of the number of these squares
labeled x or y to the number of these squares labeled v
or w?
(A) 1:2
(B) 2:3
(C) 4:3
(D) 3:2
(E) 2:1
Arithmetic Ratio and proportion
By a direct count, there are 8squares labeled
x or y (5 labeled x, 3 labeled y) and there are
4squares labeled v or w (2 labeled v, 2 labeled
w). erefore, the ratio of the number of squares
labeled x or y to the number of squares labeled v
or w is 8:4, which reduces to 2:1.
e correct answer is E.
5.5 Answer Explanations
The following discussion is intended to familiarize you with the most effi cient and effective approaches
to the kinds of problems common to problem solving questions. The particular questions in this chapter
are generally representative of the kinds of problem solving questions you will encounter on the GMAT
exam. Remember that it is the problem solving strategy that is important, not the specifi c details of a
particular question.
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GMAT® Offi cial Guide 2018
184
4.
1
3
1
2
5
6
1
5
1
4
9
20
+−++− =
(A) 0
(B) 2
15
(C)
2
5
(D) 9
20
(E)
5
6
Arithmetic Operations with rational numbers
A number that is divisible by each of the
denominators is 60. erefore, 60 can be used as a
common denominator, which gives the following:
20
60
30
60
50
60
12
60
15
60
27
60
20 30 50 12 15 27
60
0
60 0.
+−++−=
+−++− ==
e correct answer is A.
5. Bouquets are to be made using white tulips and red
tulips, and the ratio of the number of white tulips to
the number of red tulips is to be the same in each
bouquet. If there are 15 white tulips and 85 red tulips
available for the bouquets, what is the greatest number
of bouquets that can be made using all the tulips
available?
(A) 3
(B) 5
(C) 8
(D) 10
(E) 13
Arithmetic Applied problems; Properties of
numbers
Because all the tulips are to be used and the same
number of white tulips will be in each bouquet,
the number of white tulips in each bouquet times
the number of bouquets must equal the total
number of white tulips, or 15. us, the number
of bouquets must be a factor of 15, and so the
number must be 1, 3, 5, or 15. Also, the number
of red tulips in each bouquet times the number
of bouquets must equal the total number of red
tulips, or 85. us, the number of bouquets must
be a factor of 85, and so the number must be 1, 5,
17, or 85. Since the number of bouquets must be
1, 3, 5, or 15, and the number of bouquets must
be 1, 5, 17, or 85, it follows that the number of
bouquets must be 1 or 5, and thus the greatest
number of bouquets that can be made is 5. Note
that each of the 5bouquets will have 3white
tulips, because (5)(3)=15, and each of the
5bouquets will have 17red tulips, because (5)
(17)=85.
e correct answer is B.
6. 125% of 5 =
(A) 5.125
(B) 5.25
(C) 6
(D) 6.125
(E) 6.25
Arithmetic Percents
125% of 5 represents 125
100 ×5, or 1.25×5=6.25.
e correct answer is E.
7. Today Rebecca, who is 34 years old, and her daughter,
who is 8 years old, celebrate their birthdays. How
many years will pass before Rebecca’s age is twice her
daughter’s age?
(A) 10
(B) 14
(C) 18
(D) 22
(E) 26
Algebra Applied problems
Let x be the desired number of years. In x years,
Rebecca will be 34 + x years old and her
daughter will be 8 + x years old. From the given
information, it follows that 34+ x = 2(8 + x ). e
last equation is equivalent to 34 + x = 16 + 2 x ,
which has solution x =18.
e correct answer is C.
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5.5 Problem Solving Answer Explanations
185
8. When traveling at a constant speed of 32miles per
hour, a certain motorboat consumes 24gallons of fuel
per hour. What is the fuel consumption of this boat at
this speed measured in miles traveled per gallon of
fuel?
(A)
2
3
(B)
3
4
(C)
4
5
(D)
4
3
(E)
3
2
Arithmetic Operations with rational numbers
If the motorboat consumes 24 gallons of fuel
in 1hour, then it consumes 1gallon of fuel in
1
24hour. If the motorboat travels 32miles in
1hour, then it travels 32
24 =4
3miles in 1
24hour,
which is the length of time it takes to consume
1gallon of fuel. us, the motorboat travels
4
3miles per gallon of fuel.
e correct answer is D.
9. A case contains c cartons. Each carton contains
b boxes, and each box contains 100 paper clips.
Howmany paper clips are contained in 2 cases?
(A) 100 bc
(B) b
c
100
(C) 200 bc
(D) b
c
200
(E) bc
200
Algebra Simplifying algebraic expressions
Each case has bc boxes, each of which has
100paper clips. e total number of paper clips
in 2 cases is thus 2( )(100) 200 .bc bc=
e correct answer is C.
10. A technician makes a round‐trip to and from a certain
service center by the same route. If the technician
completes the drive to the center and then completes
10percent of the drive from the center, what percent
of the round‐trip has the technician completed?
(A) 5%
(B) 10%
(C) 25%
(D) 40%
(E) 55%
Arithmetic Percents
In completing the drive to the service center, the
technician has completed 50% of the round‐trip.
e drive from the center is the other 50% of
the round‐trip. In completing 10% of the drive
from the center, the technician has completed
an additional 10% of 50%, or 5% of the
round‐trip. us, the technician has completed
50%+5%=55% of the round‐trip.
e correct answer is E.
11. Raffle tickets numbered consecutively from 101
through 350 are placed in a box. What is the
probability that a ticket selected at random will have a
number with a hundreds digit of 2?
(A)
2
5
(B)
2
7
(C)
33
88
(D) 99
250
(E)
100
249
Arithmetic Probability
ere are 250 integers from 101 to 350 inclusive,
100 of which (that is, 200 through 299) have a
hundreds digit of 2. erefore, the probability that
a ticket selected from the box at random will have
a hundreds digit of 2 can be expressed as 100
250
2
5
=.
e correct answer is A.
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12. When Leo imported a certain item, he paid a 7 percent
import tax on the portion of the total value of the item in
excess of $1,000. If the amount of the import tax that
Leo paid was $87.50, what was the total value of the item?
(A) $1,600
(B) $1,850
(C) $2,250
(D) $2,400
(E) $2,750
Algebra First-degree equations
Letting x represent the total value of the item,
convert the words to symbols and solve the equation.
7% of value in excess of $1,000 87.50
0.07( 1,000) 87.50
1, 000 1, 250
2, 250
x
x
x
=
−=
−=
=
e correct answer is C.
13. A collection of 16coins, each with a face value of either
10cents or 25cents, has a total face value of $2.35.
How many of the coins have a face value of 25cents?
(A) 3
(B) 5
(C) 7
(D) 9
(E) 11
Algebra First-degree equations
Let x represent the number of coins each with
a face value of 25cents. en, since there are
16coins in all, 16– x represents the number of
coins each with a face value of 10cents. e total
face value of the coins is $2.35 or 235cents so,
25 x +10(16– x ) =235 given
25 x +160–10 x =235 distributive property
15 x +160 =235 combine like terms
15 x =75 subtract 160 from both sides
x =5 divide both sides by 15
erefore, 5 of the coins have a face value of
25cents.
e correct answer is B.
14. The numbers of cars sold at a certain dealership on
six of the last seven business days were 4, 7, 2, 8, 3,
and 6, respectively. If the number of cars sold on the
seventh business day was either 2, 4, or 5, for which
of the three values does the average (arithmetic mean)
number of cars sold per business day for the seven
business days equal the median number of cars sold
per day for the seven days?
I. 2
II. 4
III. 5
(A) II only
(B) III only
(C) I and II only
(D) II and III only
(E) I, II, and III
Arithmetic Statistics
Listed in numerical order, the given numbers are
2, 3, 4, 6, 7, and 8. If the seventh number were 2
or 4, then the numbers in numerical order would
be 2, 2, 3, 4, 6, 7, and 8 or 2, 3, 4, 4, 6, 7, and 8.
In either case the median would be 4 and the
average would be 2234678
7
32
7or
++++++=
2344678
7
34
7
++++++=, neither of which
equals 4. So, for neither of the values in I or
II does the average equal the median. If the
seventh number were 5, then the numbers in
numerical order would be 2, 3, 4, 5, 6, 7, and 8.
e median would be 5 and the average would
be 2345678
7
35
75.
++++++== us, for the
value in III, the average equals the median.
e correct answer is B.
15. If it is assumed that 60 percent of those who receive a
questionnaire by mail will respond and 300responses
are needed, what is the minimum number of
questionnaires that should be mailed?
(A) 400
(B) 420
(C) 480
(D) 500
(E) 600
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5.5 Problem Solving Answer Explanations
187
Arithmetic Percents
From the given information, 60% of the
minimum number of questionnaires is equal to
300. is has the form “60% of what number
equals 300,” and the number can be determined
by dividing 300 by 60%. Performing the
calculation gives 300 60
100 300 100
60 500.÷=×=
e correct answer is D.
16. If 1 < x < y < z, which of the following has the greatest
value?
(A) z(x + 1)
(B) z(y + 1)
(C) x(y + z)
(D) y(x + z)
(E) z(x + y)
Algebra Inequalities
is problem can be solved by calculating each
of the options for a xed and appropriate choice
of values for each of the variables. For example, if
x=2, y=3, and z=4, then 1<x<y<z and the
values of the options are as follows:
A z(x+1)=4(2+1)=12
B z(y+1)=4(3+1)=16
C x(y+z)=2(3+4)=14
D y(x+z)=3(2+4)=18
E z(x+y)=4(2+3)=20
is problem can also be solved by the use of
algebraic ordering principles in a way that does
not assume the same answer option is true
for each choice of values of x, y, and z such
that 1<x<y<z. First, note that neither the
value of the expression in A nor the value of
the expression in B can ever have the greatest
value, since the value of the expression in E is
greater than the value of the expression in A
(because y>1) and the value of the expression
in E is greater than the value of the expression
in B (because x>1). Also, the value of the
expression in D is greater than the value of the
expression in C, since y>x implies yz>xz,
which implies xy+yz>xy+xz, which implies
y(x+z)>x(y+z), and so the value of the
expression in C cannot be the greatest. Finally,
the value of the expression in E is greater than
the value of the expression in D, since z>y
implies xz>xy, which implies xz+yz>xy+yz,
which implies z(x+y)>y(x+z), and so the value
of the expression in D cannot be the greatest.
Since none of the values of the expressions in A,
B, C, or D can be the greatest, it follows that the
value of the expression in E is the greatest.
e correct answer is E.
17. A rectangular garden is to be twice as long as it is
wide. If 360 yards of fencing, including the gate, will
completely enclose the garden, what will be the length
of the garden, in yards?
(A) 120
(B) 140
(C) 160
(D) 180
(E) 200
Geometry Quadrilaterals; Perimeter
Let the width of the rectangle be x . en the
length is 2 x . Since the perimeter of a rectangle is
twice the sum of the length and width, it follows
that
360 2 2
360 6
120 2
xx
x
x
(
)
=+
=
=
So, the length is 120.
e correct answer is A.
18. A rectangular floor that measures 8 meters by
10meters is to be covered with carpet squares that
each measure 2 meters by 2 meters. If the carpet
squares cost $12 apiece, what is the total cost for the
number of carpet squares needed to cover the floor?
(A) $200
(B) $240
(C) $480
(D) $960
(E) $1,920
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Geometry Area (Rectangles)
e area of the oor is (10 m)(8 m) = 80 m
2 and
the area of each carpet square is (2 m)(2 m) = 4 m
2 .
erefore, the number of carpet squares needed
to cover the oor is 80
4 = 20, and these 20 carpet
squares have a total cost of (20)($12) = $240.
e correct answer is B.
19. If 893 × 78 = p , which of the following is equal to
893 × 79?
(A) p + 1
(B) p + 78
(C) p + 79
(D) p + 893
(E) p + 894
Arithmetic Properties of numbers
893 × 79 = 893 × (78 + 1) since 79 = 78 + 1
= (893 × 78) + 893 distributive property
= p + 893 since p = 893 × 78
e correct answer is D.
20. Thabo owns exactly 140books, and each book is
either paperback ction, paperback non ction, or
hardcover non ction. If he owns 20more paperback
non ction books than hardcover non ction books, and
twice as many paperback ction books as paperback
non ction books, how many hardcover non ction
books does Thabo own?
(A) 10
(B) 20
(C) 30
(D) 40
(E) 50
Algebra Simultaneous fi rst-degree equations
Let F represent the number of paperback ction
books that abo owns; N
p , the number of
paperback non ction books; and N
h , the number
of hardcover non ction books. It is
given that F + N
p + N
h =140, N
p = N
h +20, and
F =2 N
p =2( N
h +20). It follows that
F + N
p + N
h =140 given
2( N
h +20)+( N
h +20)+ N
h =140 by substitution
4 N
h +60 =140 combine like
terms
4 N
h = 80 subtract 60
from both sides
N
h = 20 divide both
sides by 4
e correct answer is B.
21. If the average (arithmetic mean) of the four numbers 3,
15, 32, and ( N + 1) is 18, then N =
(A) 19
(B) 20
(C) 21
(D) 22
(E) 29
Arithmetic Statistics
From the given information and the
de nition of average, it follows that
+++ +=+=
NN31532( 1)
418, or 51
418.
Multiplying both sides of the last equation by 4
gives 51 + N = 72. erefore, N = 72 – 51 = 21.
e correct answer is C.
22. Abdul, Barb, and Carlos all live on the same straight
road, on which their school is also located. The school
is halfway between Abdul’s house and Barb’s house.
Barb’s house is halfway between the school and
Carlos’s house. If the school is 4 miles from Carlos’s
house, how many miles is Abdul’s house from Carlos’s
house?
(A) 11
3
(B) 2
(C) 4
(D) 6
(E) 8
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5.5 Problem Solving Answer Explanations
189
Geometry Applied problems
In the diagram, A represents the location of
Abdul’s house, S represents the location of the
school, B represents the location of Barb’s house,
and C represents the location of Carlos’s house.
Because the school is halfway between Abdul’s
house and Barb’s house, S is the midpoint of ,AB
and because Barb’s house is halfway between
the school and Carlos’s house, B is the midpoint
of SC. erefore, AS=SB=BC. Finally, since
SC=4, it follows that AS=SB=BC=2 and
hence AC=2+2+2=6.
A
SB
C
e correct answer is D.
23. During a certain time period, Car X traveled north
along a straight road at a constant rate of 1 mile per
minute and used fuel at a constant rate of 5 gallons
every 2 hours. During this time period, if Car X used
exactly 3.75 gallons of fuel, how many miles did Car X
travel?
(A) 36
(B) 37.5
(C) 40
(D) 80
(E) 90
Arithmetic Applied problems
e car traveled at a rate of
1mi
min 1mi
min 60 min
hr 60 mi
hr
=⎛
⎝
⎜⎞
⎠
⎟⎛
⎝
⎜⎞
⎠
⎟= using fuel
at a rate of 5gallons every 2hours, or 5
2
gal
hr . If
the usage rate in miles per gallon was known,
then that usage rate times 3.75gallons would give
the number of miles.
One approach to nding this usage rate
is to consider whether multiplying or
dividing the known rates 60 mi
hr and 5
2
gal
hr
will lead to unit cancellations that result in
miles per gallon. e following calculation
shows that dividing these two known rates
leads to the appropriate unit cancellations:
60 mi
hr
5
2
gal
hr 60 mi
hr
2
5
hr
gal 24 mi
gal .÷= ×=
erefore, after using 3.75gal of fuel, the car has
traveled 24 mi
gal 3.75 gal 90 miles.×=
e correct answer is E.
24. Cheryl purchased 5 identical hollow pine doors and
6identical solid oak doors for the house she is
building. The regular price of each solid oak door
was twice the regular price of each hollow pine door.
However, Cheryl was given a discount of 25% off the
regular price of each solid oak door. If the regular price
of each hollow pine door was $40, what was the total
price of all 11doors?
(A) $320
(B) $540
(C) $560
(D) $620
(E) $680
Algebra Applied problems; Percents
e price of each pine door is $40, so the price of
5pine doors is 5($40)=$200. e price of each
oak door is twice that of a pine door, and thus
$80, which becomes (0.75)($80)=$60 when the
25% discount is applied. erefore, the price of
6oak doors at the 25% discount is 6($60)=$360,
and hence the total price of all 11doors is
$200+$360=$560.
e correct answer is C.
25. If y1
2
11
2
−<, which of the following could be a value
of y ?
(A) −11
(B) 11
2
−
(C)
11
2
(D) 11
(E) 22
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Algebra Inequalities; Absolute value
Since 1
2
11
2
y−< is equivalent to
11
2
1
2
11
2,or 10
2
12
2,yy−<−< −<< select the
value that lies between 10
25and 12
26.−=− =
at value is 11
2.
e correct answer is C.
B
CD
120°
A
26. In the gure shown, AC = 2 and BD = DC = 1. What is
the measure of angle ABD ?
(A) 15°
(B) 20°
(C) 30°
(D) 40°
(E) 45°
Geometry Triangles
Since AC=AD+DC, and it is given that AC=2
and DC=1, it follows that AD=1. erefore,
AD=BD=1 and ΔABD is an isosceles triangle
where the measure of ∠ABD is equal to the
measure of ∠BAD. Letting x° be the common
degree measure of these two angles, it follows that
x°+x°+120°=180°, or 2x°=60°, or x°=30°.
e correct answer is C.
27. If km
22
=, which of the following must be true?
(A) k = m
(B) k = − m
(C) k = |m|
(D) k = − |m|
(E) |k| = |m|
Algebra Simplifying algebraic expressions
One method of solving this is to rst take
the nonnegative square root of both sides of
the equation 22
km= and then make use of the
fact that =
2
uu
. Doing this gives | k | = | m |.
Alternatively, if ( k , m ) is equal to either of
the pairs (1,1) or (–1,1), then 22
km= is true.
However, each of the answer choices except
| k | = | m | is false for at least one of these two
pairs.
e correct answer is E.
28. Makoto, Nishi, and Ozuro were paid a total of $780
for waxing the oors at their school. Each was paid in
proportion to the number of hours he or she worked. If
Makoto worked 15hours, Nishi worked 20hours, and
Ozuro worked 30hours, how much was Makoto paid?
(A) $52
(B) $117
(C) $130
(D) $180
(E) $234
Arithmetic Ratio and proportion
Makoto, Nishi, and Ozuro worked a total of
15+20+30=65hours and were paid a total of
$780. Each was paid in proportion to the number
of hours he or she worked. erefore, Makoto was
paid 15
65($780)=$180.
e correct answer is D.
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5.5 Problem Solving Answer Explanations
191
6
8
PQ
R
29. The gure above shows a path around a triangular
piece of land. Mary walked the distance of 8 miles
from P to Q and then walked the distance of 6miles
from Q to R . If Ted walked directly from P to R , by what
percent did the distance that Mary walked exceed the
distance that Ted walked?
(A) 30%
(B) 40%
(C) 50%
(D) 60%
(E) 80%
Geometry Pythagorean theorem
Mary walked a distance of 6 + 8 = 14 miles.
e distance that Ted walked, PR , can be
found by using the Pythagorean theorem
6 8 ( ) , or ( ) 100.
22 2 2
PR PR+= = Taking square
roots, it follows that Ted walked 10 miles.
erefore, the distance Mary walked exceeded the
distance Ted walked by 14 – 10 = 4 miles and 4 is
40% of 10.
e correct answer is B.
30. At a supermarket, John spent 1
2 of his money on fresh
fruits and vegetables, 1
3 on meat products, and 1
10
on bakery products. If he spent the remaining $6 on
candy, how much did John spend at the supermarket?
(A) $60
(B) $80
(C) $90
(D) $120
(E) $180
Arithmetic Fractions
e amount spent was
1
2
1
3
1
10
15
30
10
30
3
30
28
30
14
15
++=++== of the total
so the $6 left was 1
15 of the total. It follows that
the total is (15)($6) = $90.
e correct answer is C.
31. If (1 – 1.25) N = 1, then N =
(A) –400
(B) –140
(C) –4
(D) 4
(E) 400
Algebra Operations with rational numbers
Since (1 – 1.25) N = –0.25 N = 1
4
− N , the equation
becomes – 1
4 N = 1, which has solution N = –4.
e correct answer is C.
32. A carpenter constructed a rectangular sandbox with
a capacity of 10 cubic feet. If the carpenter were to
make a similar sandbox twice as long, twice as wide,
and twice as high as the rst sandbox, what would be
the capacity, in cubic feet, of the second sandbox?
(A) 20
(B) 40
(C) 60
(D) 80
(E) 100
Geometry Volume
When all the dimensions of a three‐dimensional
object are changed by a factor of 2, the
capacity, or volume, changes by a factor of
(2)(2)(2)=2
3 =8. us the capacity of the second
sandbox is 10(8)=80 cubic feet.
e correct answer is D.
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33. The quotient when a certain number is divided by 2
3 is
9
2. What is the number?
(A) 4
27
(B)
1
3
(C) 3
(D) 6
(E) 27
4
Arithmetic Operations with rational numbers
Recall the de nition of division: a÷b=c means
a=bc. For example, if a certain number divided
by 2 equals 3, then the number is 2×3=6. For
this problem, a certain number divided by 2
3
equals 9
2, so the number is 2
3
9
23.×=
is problem can also be solved by algebra. Let N
be the number. en 2
3
9
2,
N= or 2
3
9
23.N=×=
e correct answer is C.
34. If a sphere with radius r is inscribed in a cube with
edges of length e, which of the following expresses the
relationship between r and e?
(A) r = 1
2e
(B) r = e
(C) r = 2e
(D) r = e
(E) r = 1
4
2
e
Geometry Volume
A sphere inscribed in a cube touches, but does
not extend beyond, each of the 6sides of the
cube, and thus the diameter of the sphere is equal
to the distance between a pair of opposite sides of
the cube, which is equal to the edge length of the
cube. erefore, the radius of the sphere is equal
to half the edge length of the cube, or 1
2.
r
e=
e correct answer is A.
35. If 2 x + y = 7 and x + 2 y = 5, then xy
3
+=
(A) 1
(B)
4
3
(C)
17
5
(D)
18
5
(E) 4
Algebra Simultaneous equations
Adding the equations 2 x + y = 7 and x + 2 y = 5
gives 3 x + 3 y = 12, or x + y = 4. Dividing both
sides of the last equation by 3 gives 3
4
3.
xy+=
e correct answer is B.
36. CityX has a population 4times as great as the
population of CityY, which has a population twice as
great as the population of CityZ. What is the ratio of
the population of CityX to the population of CityZ?
(A) 1:8
(B) 1:4
(C) 2:1
(D) 4:1
(E) 8:1
Arithmetic Ratio and Proportion
Let X , Y , and Z be the populations of CitiesX,
Y, and Z, respectively. It is given that X =4 Y ,
and Y =2 Z or Z =2
Y. en,
X
Z=4
2
Y
Y=
(4 Y ) 2
Y
⎛
⎝
⎜⎞
⎠
⎟=8
1.
e correct answer is E.
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193
Tides at Bay Cove on July 13
11:30 a.m.
2.2 ft
4:30 a.m.
0.3 ft
6 p.m.
–0.5 ft
6 a.m.
–1
0
1
2
3
noon midnight
time
height of tide
37. The graph above shows the height of the tide, in feet,
above or below a baseline. Which of the following is
closest to the difference, in feet, between the heights
of the highest and lowest tides on July 13 at Bay Cove?
(A) 1.7
(B) 1.9
(C) 2.2
(D) 2.5
(E) 2.7
Arithmetic Interpretation of graphs and tables
From the graph, the highest tide is 2.2 ft above
the baseline and the lowest tide is 0.5 ft below the
baseline. erefore, the di erence between the
heights of the highest tide and the lowest tide
is [2.2 – (–0.5)] ft = (2.2 + 0.5) ft = 2.7 ft.
e correct answer is E.
38. A manufacturer of a certain product can expect that
between 0.3 percent and 0.5 percent of the units
manufactured will be defective. If the retail price is
$2,500 per unit and the manufacturer offers a full
refund for defective units, how much money can the
manufacturer expect to need to cover the refunds on
20,000 units?
(A) Between $15,000 and $25,000
(B) Between $30,000 and $50,000
(C) Between $60,000 and $100,000
(D) Between $150,000 and $250,000
(E) Between $300,000 and $500,000
Arithmetic Applied problems
e expected number of defective units is
between 0.3% and 0.5% of 20,000, or between
(0.003)(20,000) = 60 and (0.005)(20,000) = 100.
Since each unit has a retail price of $2,500, the
amount of money needed to cover the refunds
for the expected number of defective units is
between 60($2,500) and 100($2,500), or between
$150,000 and $250,000.
e correct answer is D.
house
patio
40ft
35ft
20ft
15ft
39. A flat patio was built alongside a house as shown in the
gure above. If all angles shown are right angles, what
is the area of the patio in square feet?
(A) 800
(B) 875
(C) 1,000
(D) 1,100
(E) 1,125
Geometry Area
20
15
40
35
20
e area of the patio can be calculated by
imagining the patio to be a rectangle of dimensions
40 ft by 35 ft that has a lower‐left square corner of
dimensions 20 ft by 20 ft covered up, as shown in
the gure above. e area of the patio will be the
area of the uncovered part of the rectangle, and
therefore the area of the patio, in square feet, is
(40)(35) – (20)(20) = 1,400 – 400 = 1,000.
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20
15
40 40
35
20
20
15 35
20
Alternatively, the area of the patio can be
calculated by dividing the patio into two
rectangles and adding the areas of the two
rectangles. is can be done in two ways:
by using rectangles of dimensions 20 ft by
35 ft and 20 ft by 15 ft, as shown in the gure
above on the left (for a total area of
700 ft
2 + 300 ft
2 = 1,000 ft
2 ), or by using
rectangles of dimensions 40 ft by 15 ft
and 20 ft by 20 ft, as shown in the gure
above on the right (for a total area of
600 ft
2 + 400 ft
2 = 1,000 ft
2 ).
e correct answer is C.
40. The sum of the weekly salaries of 5 employees is
$3,250. If each of the 5salaries is to increase by
10percent, then the average (arithmetic mean) weekly
salary per employee will increase by
(A) $52.50
(B) $55.00
(C) $57.50
(D) $62.50
(E) $65.00
Arithmetic Applied problems; Percents
Let S1, S2, S3, S4, and S5 be the salaries,
in dollars, of the 5employees. Since
the sum of the 5salaries is 3,250, then
S1+S2+S3+S4+S5=3,250 and the average
salary is 5
12 3 4 5
SS S S S++++=3, 250
5=650.
After each salary is increased by 10%, the salaries
will be (1.1)S1, (1.1)S2, (1.1)S3, (1.1)S4, and
(1.1)S5 and the average salary, in dollars, will be
(1.1) (1.1) (1.1) (1.1) (1.1)
5
12345
SSSSS++++=
1.1×5
12 3 45
SS S SS++ ++
⎛
⎝
⎜⎞
⎠
⎟=1.1×650=715.
erefore, the increase in the average salary is
$715–$650=$65.
e correct answer is E.
41. A student’s average (arithmetic mean) test score on
4 tests is 78. What must be the student’s score on a
5th test for the student’s average score on the 5 tests
to be 80?
(A) 80
(B) 82
(C) 84
(D) 86
(E) 88
Arithmetic Statistics
e average of the student’s rst 4 test scores
is 78, so the sum of the rst 4 test scores is
4 78 312.
()
= If x represents the fth test score,
then the sum of all 5 test scores is 312 x+ and
the average of all 5 test scores is 312
5
x+. But the
average of all 5 test scores is 80 so
312
580
312 400
88
x
x
x
+=
+=
=
e correct answer is E.
42. Last week Chris earned x dollars per hour for the rst
40hours worked plus 22dollars per hour for each
hour worked beyond 40hours. If last week Chris
earned a total of 816dollars by working 48hours,
what is the value of x?
(A) 13
(B) 14
(C) 15
(D) 16
(E) 17
Algebra Applied problems
Chris worked 40hours at a rate of $xper hour,
48–40=8hours at a rate of $22per hour, and
earned a total of $816.
40x + 8(22) =816 given information
40x + 176 =816 multiply 8 and 22
40x=640 subtract 176 from both sides
x=16 divide both sides by 40
e correct answer is D.
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5.5 Problem Solving Answer Explanations
195
B
C
A
(
y
+ 10)°
y
°
43. In the gure above, what is the ratio of the measure of
angle B to the measure of angle A ?
(A) 2 to 3
(B) 3 to 4
(C) 3 to 5
(D) 4 to 5
(E) 5 to 6
Geometry Angles
Because the sum of the degree measures of the
three interior angles of a triangle is 180, it follows
that y + ( y + 10) + 90 = 180. erefore, 2 y = 80,
and hence y = 40. e ratio of the measure of
angle B to the measure of angle A can now be
determined: 10
y
y+=40
50=4
5.
e correct answer is D.
44. If n is a prime number greater than 3, what is the
remainder when n
2 is divided by 12?
(A) 0
(B) 1
(C) 2
(D) 3
(E) 5
Arithmetic Properties of numbers
e simplest way to solve this problem is to
choose a prime number greater than 3 and divide
its square by 12 to see what the remainder is. For
example, if n = 5, then n
2 = 25, and the remainder
is 1 when 25 is divided by 12. A second prime
number can be used to check the result. For
example, if n = 7, then n
2 = 49, and the remainder
is 1 when 49 is divided by 12. Because only one of
the answer choices can be correct, the remainder
must be 1.
For the more mathematically inclined, consider the
remainder when each prime number n greater than
3 is divided by 6. e remainder cannot be 0 because
that would imply that n is divisible by 6, which is
impossible since n is a prime number. e remainder
cannot be 2 or 4 because that would imply that n is
even, which is impossible since n is a prime number
greater than 3. e remainder cannot be 3 because
that would imply that n is divisible by 3, which is
impossible since n is a prime number greater than
3. erefore, the only possible remainders when a
prime number n greater than 3 is divided by 6 are
1 and 5. us, n has the form 6 q + 1 or 6 q + 5,
where q is an integer, and, therefore, n
2 has the
form 36 q
2 + 12 q + 1 = 12(3 q
2 + q ) + 1 or
36 q
2 + 60 q + 25 = 12(3 q
2 + 5 q + 2) + 1. In either
case, n
2 has a remainder of 1 when divided by 12.
e correct answer is B.
45.
+
−
+
=
1
11
3
1
11
2
(A) 1
3
−
(B) 1
6
−
(C) 1
12
−
(D) 1
12
(E)
1
3
Arithmetic Operations with rational numbers
Perform the arithmetic calculations as follows:
1
11
3
1
11
2
1
4
3
1
3
2
3
4
2
3
9
12
8
12
98
12
1
12
+−+=−
=−
=−
=−
=
e correct answer is D.
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46. The positive two‐digit integers x and y have the same
digits, but in reverse order. Which of the following must
be a factor of x + y ?
(A) 6
(B) 9
(C) 10
(D) 11
(E) 14
Arithmetic Properties of numbers
Let m and n be digits. If x = 10 m + n , then
y = 10 n + m . Adding x and y gives
x + y = (10 m + n ) + (10 n + m ) = 11 m + 11 n =
11( m + n ), and therefore 11 is a factor of x + y .
e correct answer is D.
47. In a certain sequence of 8 numbers, each number
after the rst is 1 more than the previous number. If
the rst number is –5, how many of the numbers in the
sequence are positive?
(A) None
(B) One
(C) Two
(D) Three
(E) Four
Arithmetic Sequences
e sequence consists of eight consecutive
integers beginning with –5:
5, 4, 3, 2, 1, 0, 1, 2−− − − −
In this sequence exactly two of the numbers are
positive.
e correct answer is C.
48. A total of s oranges are to be packaged in boxes that
will hold r oranges each, with no oranges left over.
When n of these boxes have been completely lled,
what is the number of boxes that remain to be lled?
(A) s – nr
(B) s – n
r
(C) rs – n
(D)
s
n – r
(E)
s
r – n
Algebra Algebraic expressions
If s oranges are packed r oranges to a box with no
oranges left over, then the number of boxes that
will be lled is s
r. If n of these boxes are already
lled, then s
r– n boxes remain to be lled.
e correct answer is E.
49. If 0 < a < b < c , which of the following statements must
be true?
I. 2 a > b + c
II. c – a > b – a
III. c
a
b
a
<
(A) I only
(B) II only
(C) III only
(D) I and II
(E) II and III
Algebra Inequalities
Given 0 < a < b < c , Statement I is not necessarily
true. If, for example, a =1, b =2, and c =3, then
0 < a < b < c , but 2 a =2(1) < 2+3= b + c .
Given 0 < a < b < c , then c > b , and subtracting
a from both sides gives c – a > b – a . erefore,
Statement II is true.
Given 0 < a < b < c , Statement III is not
necessarily true. If, for example, a =1, b =2, and
c =3, then 0 < a < b < c , but c
a=3
1>2
1=b
a.
e correct answer is B.
50. In the xy-plane, the origin O is the midpoint of line
segment PQ. If the coordinates of P are (r,s), what are
the coordinates of Q?
(A) (r,s)
(B) (s,–r)
(C) (–s,–r)
(D) (–r,s)
(E) (–r,–s)
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5.5 Problem Solving Answer Explanations
197
Algebra Coordinate geometry
Let (x,y) be the coordinates of Q. e midpoint
of (r,s) and (x,y) is 2,2
rx
sy
++
⎛
⎝
⎜⎞
⎠
⎟. Since the
midpoint is (0,0), it follows that 2
rx+=0 and
2
sy+=0. erefore, r+x=0 and s+y=0, or
x=–r and y=–s, or (x,y)=(–r,–s).
is problem can also be solved by observing that
Q is the re ection of P about the origin, and so
Q=(–r,–s) (i.e., change the sign of each of the
coordinates of P to obtain the coordinates of Q).
e correct answer is E.
51. Which of the following equations is NOT equivalent to
10 y
2 = ( x + 2)( x – 2)?
(A) 30 y
2 = 3 x
2 – 12
(B) 20 y
2 = (2 x – 4)( x + 2)
(C) 10 y
2 + 4 = x
2
(D) 5 y
2 = x
2 – 2
(E)
yx4
10
22
=−
Algebra Simplifying algebraic expressions
When x = 2 or x = –2, the equation becomes
10 y
2 = 0, or y = 0. Since, in the equation given in
(D), y does not become 0 when x = 2, it follows
that the equation given in (D) is not equivalent
to the given equation. Alternatively, when each of
the equations given in (A) through (E) is solved
for 10 y
2 in terms of x , only the resulting equation
in (D) fails to give an expression in terms of x
that is equivalent to ( x + 2)( x – 2) = x
2 – 4.
e correct answer is D.
Monday Tuesday Wednesday Thursday
Company A 45 55 50 50
Company B 10 30 30 10
Company C 34 28 28 30
Company D 39 42 41 38
Company E 50 60 60 70
52. The table shows the numbers of packages shipped
daily by each of ve companies during a 4‐day period.
The standard deviation of the numbers of packages
shipped daily during the period was greatest for which
of the ve companies?
(A) A
(B) B
(C) C
(D) D
(E) E
Arithmetic Statistics
Since the standard deviation of a data set is a
measure of how widely the data are scattered
about their mean, nd the mean number of
packages shipped by each company and then
determine the company for which the data is
most widely scattered about its mean.
For CompanyA, the mean number of packages
shipped is 45 55 2(50)
4
++ =50. Two of the data
points are each 50 and the other two each di er
from 50 by 5.
For CompanyB, the mean number of packages
shipped is 2(10) 2(30)
4
+=20. Each of the data
points di ers from 20 by 10. us, the data for
CompanyB is more widely scattered about its
mean of 20 than the data for CompanyA is
about its mean of 50.
For CompanyC, the mean number of packages
shipped is 34 2(28) 30
4
++
=30. One data point
is 30, two others each di er from 30 by only 2,
and the fourth data point di ers from 30 by only 4.
erefore, the data for CompanyC is not as
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GMAT® Offi cial Guide 2018
198
widely scattered about its mean of 30 as the data
for CompanyB is about its mean of 20.
For CompanyD, the mean number of packages
shipped is 39 42 41 38
4
+++
=40. Two of
the data points each di er from 40 by only 1
and the other two each di er from 40 by only
2. erefore, the data for CompanyD is not as
widely scattered about its mean of 40 as the data
for CompanyB is about its mean of 20.
For CompanyE, the mean number of packages
shipped is 50 2(60) 70
4
++
=60. Two of the
data points are each 60 and the other two each
di er from 60 by 10. erefore, the data for
CompanyE is not as widely scattered about its
mean of 60 as the data for CompanyB is about
its mean of 20.
us, the data for CompanyB is most widely
scattered about its mean and, therefore, the
standard deviation of the number of packages
shipped daily by the ve companies is greatest for
CompanyB.
For those interested, the standard deviations for
the ve companies can be calculated as follows:
For A: (45 50) (55 50) 2(50 50)
4
22 2
−+−+−
=2(25)
4=25
2=12.5.
For B: 2(10 20) 2(30 20)
4
22
−+−=4(100)
4
=100.
For C: (34 30) 2(28 30) (30 30)
4
222
−+−+−
=24
4=6.
For D:
(39 40) (42 40) (41 40) (38 40)
4
2222
−+−+−+−
=10
4=2.5.
For E: (50 60) 2(60 60) (70 60)
4
222
−+−+−
=200
4=50 .
e correct answer is B.
53. CompanyQ plans to make a new product next year
and sell each unit of this new product at a selling price
of $2. The variable costs per unit in each production
run are estimated to be 40% of the selling price, and
the xed costs for each production run are estimated
to be $5,040. Based on these estimated costs, how
many units of the new product will CompanyQ need to
make and sell in order for their revenue to equal their
total costs for each production run?
(A) 4,200
(B) 3,150
(C) 2,520
(D) 2,100
(E) 1,800
Algebra Applied problems
Let x be the desired number of units to be sold
at a price of $2each. en the revenue for selling
these units is $2x, and the total cost for selling
these units is (40%)($2.00)x=$0.80x plus a xed
cost of $5,040.
revenue =total cost given requirement
2x=0.8x + 5,040 given information
1.2x=5,040 subtract 0.8x from both
sides
x=4,200 divide both sides by 1.2
e correct answer is A.
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5.5 Problem Solving Answer Explanations
199
54. The dial shown above is divided into equal‐sized intervals.
At which of the following letters will the pointer stop if it
is rotated clockwise from S through 1,174intervals?
(A) A
(B) B
(C) C
(D) D
(E) E
Arithmetic Properties of numbers
ere are 8 intervals in each complete revolution.
Dividing 8 into 1,174 gives 146 with remainder
6. erefore, 1,174 intervals is equivalent
to 146complete revolutions followed by an
additional 6 intervals measured clockwise
from S , which places the pointer at E .
e correct answer is E.
Estimated Number of Home-Schooled
Students by State, January 2001
State Number (in thousands)
A 181
B 125
C 103
D 79
E 72
55. According to the table shown, the estimated number
of home-schooled students in State A is approximately
what percent greater than the number in State D?
(A) 25%
(B) 55%
(C) 100%
(D) 125%
(E) 155%
Arithmetic Percents
e percent increase from the number in StateD
to the number in StateA is
=181,000 79, 000
79,000 100 %
−×
⎛
⎝
⎜⎞
⎠
⎟expression for
percent increase
=181 79
79 100 %
−×
⎛
⎝
⎜⎞
⎠
⎟reduce fraction
=102
79 100 %×
⎛
⎝
⎜⎞
⎠
⎟subtract
≈100
80 100 %×
⎛
⎝
⎜⎞
⎠
⎟approximate
=(1.25 × 100)% divide
=125% multiply
e correct answer is D.
x
y
O
IVIII
II I
56. The graph of the equation xy = k , where k < 0, lies in
which two of the quadrants shown above?
(A) I and II
(B) I and III
(C) II and III
(D) II and IV
(E) III and IV
Algebra Coordinate geometry
If a point lies on the graph of xy = k , then the
product of the point’s x ‐ and y ‐coordinates is k .
Since k is negative, it follows that for any such point,
the product of the point’s x ‐ and y ‐coordinates is
negative. erefore, for any such point, the point’s
x ‐ and y ‐coordinates have opposite signs, and hence
the point must be in quadrant II or in quadrant IV.
e correct answer is D.
S
AE
D
C
B
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GMAT® Offi cial Guide 2018
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57. When n liters of fuel were added to a tank that was
already 1
3 full, the tank was lled to 7
9 of its capacity. In
terms of n , what is the capacity of the tank, in liters?
(A)
10
9n
(B)
4
3n
(C)
3
2n
(D)
9
4n
(E) n
7
3
Algebra Applied problems
Let C represent the capacity of the tank, in liters.
It follows that
1
3 C + n =7
9 C given
n =7
9 C –1
3 C subtract 1
3 C from both
sides
n =4
9 C combine like terms
9
4 n = C divide both sides by 4
9
e correct answer is D.
w ft
w ft
100 ft
150 ft
Note: Not drawn to scale.
58. The smaller rectangle in the gure above represents
the original size of a parking lot before its length and
width were each extended by w feet to make the larger
rectangular lot shown. If the area of the enlarged lot is
twice the area of the original lot, what is the value of w ?
(A) 25
(B) 50
(C) 75
(D) 100
(E) 200
Geometry Area
From the given information it follows that
(100 + w )(150 + w ) = 2(100)(150), or
(100 + w )(150 + w ) = (200)(150). is is a
quadratic equation that can be solved by several
methods. One method is by inspection. e left
side is clearly equal to the right side when w = 50.
Another method is by factoring. Expanding the left
side gives (100)(150) + 250 w + w
2 = (200)(150), or
w
2 + 250 w – (100)(150) = 0. Factoring the left
side gives ( w – 50)( w + 300) = 0, which has
w = 50 as its only positive solution.
e correct answer is B.
59. 1
0.75 1−=
(A) –4
(B) –0.25
(C) 0.25
(D) 0.75
(E) 4
Arithmetic Operations with rational numbers
Perform the arithmetic calculations as follows:
−=−
=−
=−
1
0.75 1
1
3
41
1
1
4
4
e correct answer is A.
60. Kevin invested $8,000for one year at a simple annual
interest rate of 6percent and invested $10,000for
one year at an annual interest rate of 8percent
compounded semiannually. What is the total amount of
interest that Kevin earned on the two investments?
(A) $880
(B) $1,088
(C) $1,253
(D) $1,280
(E) $1,296
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5.5 Problem Solving Answer Explanations
201
Arithmetic Applied problems
e amount of interest after one year is the total
value of the investment after one year minus the
total initial value of the investment. e total
value of the investment after one year is
$8,000(1.06) + $10,000(1.04)2 = $8,480 + $10,816,
so the amount of interest is ($8,480 + $10,816) –
($8,000 + $10,000) = $480 + $816 = $1,296.
e correct answer is E.
61. The harvest yield from a certain apple orchard was
350bushels of apples. If x of the trees in the orchard
each yielded 10 bushels of apples, what fraction of the
harvest yield was from these x trees?
(A) x
35
(B) x
135
−
(C) 10 x
(D) 35 – x
(E) 350 – 10 x
Algebra Algebraic expressions
Since each of the x trees yielded 10bushels, the
total number of bushels yielded by these trees
was 10 x . Since the yield of the entire orchard was
350bushels, 10
350
x=35
x was the fraction of the
total yield from these x trees.
e correct answer is A.
62. If n is an integer, which of the following must be even?
(A) n + 1
(B) n + 2
(C) 2 n
(D) 2 n + 1
(E) n
2
Arithmetic Properties of integers
A quick look at the answer choices reveals the
expression 2 n in answer choice C. 2 n is a multiple
of 2 and hence must be even.
Since only one answer choice can be correct,
the other answer choices need not be checked.
However, for completeness:
A n + 1 is odd if n is even and even if n is odd.
erefore, it is not true that n + 1 must be
even.
B n + 2 is even if n is even and odd if n is odd.
erefore, it is not true that n + 2 must be
even.
D 2 n +1 is odd whether n is even or odd.
erefore, it is not true that 2 n + 1 must be
even.
E n
2 is even if n is even and odd if n is odd.
erefore, it is not true that n
2 must be
even.
e correct answer is C.
63. The sum 7
8
1
9
+ is between
(A) 1
2and 3
4
(B) 3
4and 1
(C) 1 and 11
4
(D) 11
4and 11
2
(E) 11
2and 2
Arithmetic Operations with rational numbers
Since 1
9
1
8,7
8
1
9
7
8
1
81<+<+=, and answer
choices C, D, and E can be eliminated. Since
7
8
6
8
3
4,7
8
1
9
3
4
>= +>, and answer choice A can
be eliminated. us, 3
4
7
8
1
91.<+<
e correct answer is B.
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64. Car X averages 25.0 miles per gallon of gasoline and
Car Y averages 11.9miles per gallon. If each car is
driven 12,000 miles, approximately how many more
gallons of gasoline will Car Y use than Car X?
(A) 320
(B) 480
(C) 520
(D) 730
(E) 920
Arithmetic Applied problems
Car X uses 1 gallon of gasoline for every 25 miles
it is driven, so Car X uses 1
25 of a gallon for
every 1 mile it is driven. erefore Car X will
use 12,000 1
25
()
⎛
⎝
⎜⎞
⎠
⎟=480gallons of gasoline
when it is driven 12,000 miles. Car Y uses
1gallon of gasoline for every 11.9 or 119
10 miles
it is driven, so Car Y uses 10
119 of a gallon for
every 1 mile it is driven. erefore Car Y will use
12,000 10
119 12,000 10
120 1,000
() ()
⎛
⎝
⎜⎞
⎠
⎟≈⎛
⎝
⎜⎞
⎠
⎟= gallons
of gasoline when it is driven 12,000miles. us,
Car Y will use approximately 1,000–480 = 520
more gallons of gasoline than Car X.
e correct answer is C.
65. If y is an integer, then the least possible value of
|23 – 5 y | is
(A) 1
(B) 2
(C) 3
(D) 4
(E) 5
Arithmetic Absolute value; Operations with
integers
Since y is an integer, 23 − 5 y is also an integer.
e task is to nd the integer y for which |23 − 5 y |
is the least. If y ≥ 0, −5 y ≤ 0, and 23 − 5 y ≤ 23. On
the other hand, if y ≤0, −5 y ≥ 0, and 23 − 5 y ≥ 23.
erefore, the least possible value of |23 – 5 y |
occurs at a nonnegative value of y . From the chart
below, it is clear that the least possible integer
value of |23 − 5 y | is 2, which occurs when y = 5.
y|23 – 5y|
023
118
213
3 8
4 3
5 2
6 7
712
Alternatively, since |23 – 5 y | ≥ 0, the minimum
possible real value of |23 – 5 y | is 0. e integer
value of y for which |23 – 5 y | is least is the
integer closest to the solution of the equation
23 – 5 y = 0. e solution is ==
23
54.6y and the
integer closest to 4.6 is 5.
e correct answer is B.
66. 80 125+=
(A)
95
(B)
20 5
(C)
41 5
(D) 205
(E) 100
Arithmetic Operations with radical expressions
Rewrite each radical in the form ab, where a
and b are positive integers and b is as small as
possible, and then add.
80 125 16(5) 25(5)
16 5 25 5
45 55
95
()( )()
()
+= +
=+
=+
=
e correct answer is A.
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5.5 Problem Solving Answer Explanations
203
ykx3=+
67. In the equation above, k is a constant. If y = 17 when
x = 2, what is the value of y when x = 4 ?
(A) 34
(B) 31
(C) 14
(D) 11
(E) 7
Algebra First-degree equations
If 3ykx=+ and 17y= when 2x=, then
17 = 2 k + 3
14 = 2 k
7 = k
erefore, 73yx=+. When x = 4,
7(4) 3 31y=+=.
e correct answer is B.
68. Which of the following is greatest?
(A) 10 3
(B) 94
(C) 85
(D) 76
(E) 67
Arithmetic Operations on radical expressions
Since all the expressions represent positive
numbers, the expression that has the greatest
squared value will be the expression that has the
greatest value.
10 3 2
()
=100×3=300 (not greatest)
94
2
()
=81×4=324 (greatest)
85
2
()
=64×5=320 (not greatest)
76
2
()
=49×6=294 (not greatest)
67
2
()
=36×7=252 (not greatest)
e correct answer is B.
69. Al and Ben are drivers for SD Trucking Company. One
snowy day, Ben left SD at 8:00 a.m. heading east and
Al left SD at 11:00a.m. heading west. At a particular
time later that day, the dispatcher retrieved data
from SD’s vehicle tracking system. The data showed
that, up to that time, Al had averaged 40miles per
hour and Ben had averaged 20miles per hour. It also
showed that Al and Ben had driven a combined total
of 240miles. At what time did the dispatcher retrieve
data from the vehicle tracking system?
(A) 1:00 p.m.
(B) 2:00 p.m.
(C) 3:00 p.m.
(D) 5:00 p.m.
(E) 6:00 p.m.
Algebra Applied problems
Let t be the number of hours after 8:00a.m.
that Ben drove. en, in thours, Ben
drove 20tmiles and Al, who began driving
3hours after Ben began driving, drove
40(t–3)miles. erefore, their combined
total distance at that time can be expressed as
(20t+40t–120)miles=(60t–120)miles.
It follows that 60t–120=240, or 60t =360,
or t=6, which corresponds to 6hours after
8:00a.m. or 2:00p.m.
e correct answer is B.
70. Of the land owned by a farmer, 90 percent was
cleared for planting. Of the cleared land, 40 percent
was planted with soybeans and 50 percent of the
cleared land was planted with wheat. If the remaining
720acres of cleared land was planted with corn, how
many acres did the farmer own?
(A) 5,832
(B) 6,480
(C) 7,200
(D) 8,000
(E) 8,889
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Arithmetic Applied problems; Percents
Corn was planted on 100% – (40% + 50%) = 10%
of the cleared land, and the cleared land
represents 90% of the farmer’s land. erefore,
corn was planted on 10% of 90%, or
(0.10)(0.90) = 0.09 = 9%, of the farmer’s land. It
is given that corn was planted on 720 acres, so if
x is the number of acres the farmer owns, then
0.09 x = 720 and 720
0.09 8,000x== .
e correct answer is D.
71. At the start of an experiment, a certain population
consisted of 3 animals. At the end of each month after
the start of the experiment, the population size was
double its size at the beginning of that month. Which of
the following represents the population size at the end
of 10 months?
(A) 2
3
(B) 3
2
(C) 2(3
10 )
(D) 3(2
10 )
(E) 3(10
2 )
Arithmetic Applied problems; Sequences
e population doubles each month, so multiply
the previous month’s population by 2 to get
the next month’s population. us, at the end
of the 1st month the population will be (3)(2),
at the end of the 2nd month the population
will be (3)(2)(2), at the end of the 3rd month
the population will be (3)(2)(2)(2), and so on.
erefore, at the end of the 10th month the
population will be the product of 3 and ten
factors of 2, which equals 3(2
10 ).
e correct answer is D.
72. If
1
3
1
4
1
5
1
6
1
9
1
12
1
15
1
18 ,r+++
⎛
⎝
⎜⎞
⎠
⎟= +++
⎛
⎝
⎜⎞
⎠
⎟ then r =
(A)
1
3
(B)
4
3
(C) 3
(D) 4
(E) 12
Arithmetic Operations with rational numbers
1
3
1
4
1
5
1
6
+++
⎛
⎝
⎜⎞
⎠
⎟=1
9
1
12
1
15
1
18
r+++
⎛
⎝
⎜⎞
⎠
⎟
1
3
1
4
1
5
1
6
+++
⎛
⎝
⎜⎞
⎠
⎟=1
3
1
3
1
4
1
5
1
6
r⎛
⎝
⎜⎞
⎠
⎟+++
⎛
⎝
⎜⎞
⎠
⎟
1=1
3
r⎛
⎝
⎜⎞
⎠
⎟
3=r
Alternatively,
1
3
1
4
1
5
1
6
+++
⎛
⎝
⎜⎞
⎠
⎟=1
9
1
12
1
15
1
18
r+++
⎛
⎝
⎜⎞
⎠
⎟
20
60
15
60
12
60
10
60
+++
⎛
⎝
⎜⎞
⎠
⎟=20
180
15
180
12
180
10
180
r+++
⎛
⎝
⎜⎞
⎠
⎟
20 15 12 10
60
+++
⎛
⎝
⎜⎞
⎠
⎟=20 15 12 10
180
r+++
⎛
⎝
⎜⎞
⎠
⎟
20 15 12 10
60
+++
⎛
⎝
⎜⎞
⎠
⎟180
20 15 12 10+++
⎛
⎝
⎜⎞
⎠
⎟= r
180
60 =r
3=r
e correct answer is C.
73. If x and y are positive integers such that y is a multiple
of 5 and 3 x +4 y =200, then x must be a multiple of
which of the following?
(A) 3
(B) 6
(C) 7
(D) 8
(E) 10
Arithmetic Properties of numbers
Since it is given that y is a multiple of 5,
let y =5 q , where q is a positive integer. It is
given that 3 x +4 y =200, so 3 x +4(5 q )=200
or 3 x +20 q =200. It follows that
3 x =200–20 q =20(10– q ). Since 3 is prime and
is not a factor of 20, then 3 must be a factor of
10– q , which means the only possible values
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5.5 Problem Solving Answer Explanations
205
of q are 1, 4, and 7. is is summarized in the
following table.
q 10– q 20(10– q )3xx
1 9 180 180 60
4 6 120 120 40
7 3 60 60 20
In each case, the value of x is a multiple of 10.
Alternatively, since 3 x =20(10– q ), the factors
of the product of 3 and x must correspond to the
factors of the product of 20 and (10– q ). Since
the factors of 20 include 10, then x must have a
factor of 10, which means that x is a multiple of 10.
e correct answer is E.
74. Which of the following expressions can be written as
an integer?
I. 82 82 2
()
+
II.
(82) 82
()
III. 82 82
82
()()
(A) None
(B) I only
(C) III only
(D) I and II
(E) I and III
Arithmetic Operations with radical expressions
Expression I represents an integer because
82 82 2 82 (4)(82)
22
()()
+= = .
Expression II does not represent an integer
because (82) 82 823
= and 82
3 = 2
3 × 41
3 is
not a perfect square. Regarding this last assertion,
note that the square of any integer has the
property that each of its distinct prime factors is
repeated an even number of times. For example,
24
2 = (2
3 × 3)
2 = 2
6 × 3
2 has the prime factor 2
repeated 6 times and the prime factor 3 repeated
twice. Expression III represents an integer,
because 82 82
82
82
82 1
()()
==
.
e correct answer is E.
75. Four staff members at a certain company worked
on a project. The amounts of time that the four staff
members worked on the project were in the ratio 2 to
3 to 5 to 6. If one of the four staff members worked
on the project for 30 hours, which of the following
CANNOT be the total number of hours that the four
staff members worked on the project?
(A) 80
(B) 96
(C) 160
(D) 192
(E) 240
Arithmetic Ratio and proportion
For a certain value of x , the numbers of hours
worked on the project by the four sta members are
2 x , 3 x , 5 x , and 6 x , for a total of 16 x . It is given that
one of these four numbers is equal to 30. If 2 x = 30,
then x = 15 and 16 x = 16(15) = 240, which is (E).
If 3 x = 30, then x = 10 and 16 x = 16(10) = 160,
which is (C). If 5 x = 30, then x = 6 and
16 x = 16(6) = 96, which is (B). If 6 x = 30, then
x = 5 and 16 x = 16(5) = 80, which is (A).
e correct answer is D.
76. Pumping alone at their respective constant rates, one
inlet pipe lls an empty tank to 1
2 of capacity in 3 hours
and a second inlet pipe lls the same empty tank to
2
3 of capacity in 6 hours. How many hours will it take
both pipes, pumping simultaneously at their respective
constant rates, to ll the empty tank to capacity?
(A) 3.25
(B) 3.6
(C) 4.2
(D) 4.4
(E) 5.5
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Arithmetic Applied problems
e rst pipe can ll 1
2 of the tank in 3 hours,
which is equivalent to the rate of lling
1
231
6
÷= of the tank per hour. e second
pipe can ll 2
3 of the tank in 6hours, which is
equivalent to the rate of lling 2
361
9
÷= of the
tank per hour. Together, they can ll the tank at
a rate of 1
6
1
9
5
18
+= of the tank per hour. us,
when both pipes are used at the same time, they
will ll the tank in 18
53.6= hours.
e correct answer is B.
77. In the xy ‐coordinate plane, which of the following points
must lie on the line kx + 3 y = 6 for every possible value
of k ?
(A) (1,1)
(B) (0,2)
(C) (2,0)
(D) (3,6)
(E) (6,3)
Algebra Coordinate geometry
Substituting the various answer choices for ( x,y )
into kx + 3 y = 6 gives the following equations:
A k + 3 = 6
B 0 + 3(2) = 6
C 2 k + 3(0) = 6
D 3 k + 3(6) = 6
E 6 k + 3(3) = 6
Each of these, except for the equation in B, holds
for only one value of k . e equation in B does
not include k and therefore holds for every value
of k .
e correct answer is B.
78. If x
2 − 2 < 0, which of the following speci es all the
possible values of x ?
(A) 0 < x < 2
(B) 0 < x < 2
(C) x22−<<
(D) −2 < x < 0
(E) −2 < x < 2
Algebra Inequalities
e corresponding equality 20
2
x−= has two
solutions, 2x= and 2x=− , and thus there are
three intervals to test for inclusion in the solution
of the inequality: 2x<− , 22x−<<, and
2x>. Choose x = –2, x = 0, and x =2 from
these intervals, respectively, to test whether the
inequality holds. en for these choices, the
inequality becomes (–2)
2 – 2 < 0 (False),
(0)
2 – 2 < 0 (True), and (2)
2 – 2 < 0 (False).
erefore, the solution consists of only the
interval 22x−<<. Alternatively, the graph
of y=x
2 – 2 is easily seen to be a parabola that
opens upward with vertex at (0, –2) and
x ‐intercepts at 2x= and 2x=− . e solution
to the inequality is the set of the x ‐coordinates
of the portion of this parabola that lies below the
x ‐axis, which is 22x−<<.
e correct answer is C.
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5.5 Problem Solving Answer Explanations
207
Book number Pages in book Total pages read
1 253 253
2 110 363
3 117 480
4 170 650
5 155 805
6 50 855
7 205 1,060
8 70 1,130
9 165 1,295
10 105 1,400
11 143 1,543
12 207 1,750
79. Shawana made a schedule for reading books during
4weeks (28days) of her summer vacation. She has
checked out 12books from the library. The number of
pages in each book and the order in which she plans to
read the books are shown in the table above. She will
read exactly 50pages each day. The only exception
will be that she will never begin the next book on the
same day that she nishes the previous one, and
therefore on some days she may read fewer than
50pages. At the end of the 28thday, how many books
will Shawana have nished?
(A) 7
(B) 8
(C) 9
(D) 10
(E) 11
Arithmetic Operations with integers
Book 1: 6days—50 pages on each of Days 1–5, 3
pages on Day 6 [5(50)+3=253]
Book 2: 3days—50 pages on each of Days 7 and
8, 10 pages on Day 9 [2(50)+10=110]
Book 3: 3days—50 pages on each of Days 10 and
11, 17 pages on Day 12 [2(50)+17=117]
Book 4: 4days—50 pages on each of Days 13–15,
20 pages on Day 16 [3(50)+20=170]
Book 5: 4days—50 pages on each of Days 17–19,
5 pages on Day 20 [3(50)+5=155]
Book 6: 1day—50 pages on Day 21 [1(50)=50]
Book 7: 5days—50 pages on each of Days 22–25,
5 pages on Day 26 [4(50)+5=205]
Book 8: 2days—50 pages on Day 27, 20 pages on
Day 28 [50+20=70]
At this point, Shawana has read on a total of
28days and has nished 8books.
e correct answer is B.
80. In Western Europe, x bicycles were sold in each of
the years 1990 and 1993. The bicycle producers of
Western Europe had a 42percent share of this market
in 1990 and a 33 percent share in 1993. Which of the
following represents the decrease in the annual number
of bicycles produced and sold in Western Europe from
1990 to 1993?
(A) 9% of x
100
(B) 14% of x
100
(C) 75% of x
100
(D) 9% of x
(E) 14% of x
Arithmetic Percents
Of the x bicycles sold in Western Europe in
1990, 42% of them were produced in Western
Europe. It follows that the number of bicycles
produced and sold in Western Europe in 1990
was 0.42 x . Similarly, of the x bicycles sold in
Western Europe in 1993, 33% were produced in
Western Europe. It follows that the number of
bicycles produced and sold in Western Europe
in 1993 was 0.33 x . erefore, the decrease in
the annual number of bicycles produced and
sold in Western Europe from 1990 to 1993 was
0.42 x –0.33 x =0.09 x , which is 9% of x .
e correct answer is D.
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81. If k is a positive integer, what is the remainder when
(k+2)(k3–k) is divided by 6?
(A) 0
(B) 1
(C) 2
(D) 3
(E) 4
Algebra Properties of numbers
Since k can be any positive integer, the remainder
must be the same regardless of the value of k. If
k=2, for example, then (k+2)(k3–k)=
(2+2)(23–2)=(4)(6), which is a multiple of 6,
and therefore, the remainder when divided by
6 is 0.
Alternatively, factor the given expression:
(k+2)(k3–k)=(k+2)(k)(k2–1)
=(k+2)(k)(k+1)(k–1)
Now, rearrange the factors in ascending order
(k–1)(k)(k+1)(k+2), and observe that for any
positive integer k, the factors are 4consecutive
integers, two of which are even and one of which
is divisible by 3. erefore, (k+2)(k3–k) is
divisible by both 2 and 3. us, (k+2)(k3–k) is
divisible by 6 with 0 remainder.
e correct answer is A.
82. Which of the following fractions is closest to 1
2?
(A)
4
7
(B)
5
9
(C) 6
11
(D) 7
13
(E) 9
16
Arithmetic Fractions
Find the distance between each fraction and 1
2:
4
7
1
2
8
14
7
14
1
14
−= − =
5
9
1
2
10
18
9
18
1
18
−= − =
6
11
1
2
12
22
11
22
1
22
−= − =
7
13
1
2
14
26
13
26
1
26
−= − =
9
16
1
2
9
16
8
16
1
16
−= − =
Each distance is the reciprocal of a positive
integer, the greatest of which is 26. erefore, 1
26
is the least of the distances and 7
13 is the fraction
closest to 1
2.
Alternatively, asking which fraction is closest to
1
2 is equivalent to asking which of the fractions,
when doubled, is closest to 1. e fractions after
doubling are 8
7, 10
9, 12
11, 14
13, and 18
16=9
8. Each of
these fractions can be expressed as 1n
n
+=1+1
n
for some integer n . Of these fractions, the one
closest to 1 is the one for which 1
n is least, or in
other words, the one for which n is greatest. at
fraction is 14
13, and therefore the closest of the
original fractions to 1
2 is 1
2
14
13
⎛
⎝
⎜⎞
⎠
⎟⎛
⎝
⎜⎞
⎠
⎟=7
13.
e correct answer is D.
83. If p ≠0 and p – p
p
12
−=r
p, then r =
(A) p + 1
(B) 2 p – 1
(C) p
2 + 1
(D) 2 p
2 – 1
(E) p
2 + p – 1
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5.5 Problem Solving Answer Explanations
209
Algebra Simplifying algebraic expressions
p – 12
p
p
−=r
p
given
p
2 –(1– p
2 ) = r multiply both sides by p
2 p
2 –1 = r combine like terms
e correct answer is D.
84. If the range of the six numbers 4, 3, 14, 7, 10, and
x is 12, what is the difference between the greatest
possible value of x and the least possible value of x ?
(A) 0
(B) 2
(C) 12
(D) 13
(E) 15
Arithmetic Statistics
e range of the six numbers 3, 4, 7, 10, 14, and
x is 12. If x were neither the greatest nor the
least of the six numbers, then the greatest and
least of the six numbers would be 14 and 3. But,
this cannot be possible because the range of the
six numbers would be 14–3=11 and not 12 as
stated. erefore, x must be either the greatest or
the least of the six numbers. If x is the greatest
of the six numbers, then 3 is the least, and
x –3=12. It follows that x =15. On the other
hand, if x is the least of the six numbers, then 14
is the greatest, and 14– x =12. It follows that
x =2. us, there are only two possible values of
x , namely 15 and 2, and so the di erence between
the greatest and least possible values of x is
15–2=13.
e correct answer is D.
85. What number is 108 more than two-thirds of itself?
(A) 72
(B) 144
(C) 162
(D) 216
(E) 324
Algebra First-degree equations
Let x be the number that is 108 more than two-
thirds of itself. en, 108+2
3x=x. Solve for x as
follows:
108+2
3x=x
108 =1
3x
324 =x
e correct answer is E.
86. A doctor prescribed 18cubic centimeters of a certain
drug to a patient whose body weight was 120pounds.
If the typical dosage is 2cubic centimeters per
15pounds of body weight, by what percent was the
prescribed dosage greater than the typical dosage?
(A) 8%
(B) 9%
(C) 11%
(D) 12.5%
(E) 14.8%
Arithmetic Percents
If the typical dosage is 2cubic centimeters per
15pounds of body weight, then the typical
dosage for a person who weighs 120pounds
is 2 120
15
⎛
⎝
⎜⎞
⎠
⎟=2(8)=16cubic centimeters. e
prescribed dosage of 18cubic centimeters is,
therefore, 18 16
16 100
−
⎛
⎝
⎜⎞
⎠
⎟×
⎛
⎝
⎜⎞
⎠
⎟% or 12.5% greater
than the typical dosage.
e correct answer is D.
87. Company P had 15 percent more employees in
December than it had in January. If Company P had
460 employees in December, how many employees
did it have in January?
(A) 391
(B) 400
(C) 410
(D) 423
(E) 445
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Arithmetic Percents
It is given that 460 is 115% of the number of
employees in January. erefore, the number of
employees in January was
460
1.15
460
1.15
100
100
460
115 100 4 100 400.
()()()
=⎛
⎝
⎜⎞
⎠
⎟=⎛
⎝
⎜⎞
⎠
⎟==
e correct answer is B.
88. The function f is de ned by fx x() 10=− for all
positive numbers x . If u = f ( t ) for some positive
numbers t and u , what is t in terms of u ?
(A) u10+
(B) u10 2
()
+
(C) u10
2+
(D) ( u + 10)
2
(E) ( u
2 + 10)
2
Algebra Functions
e question can be answered by solving
ut=–10 for t in terms of u . Adding 10 to both
sides of this equation gives 10ut+=. Squaring
both sides of the last equation gives ( u + 10)
2 = t ,
which gives t in terms of u .
e correct answer is D.
89. A glass was lled with 10 ounces of water, and
0.01ounce of the water evaporated each day during a
20‐day period. What percent of the original amount of
water evaporated during this period?
(A) 0.002%
(B) 0.02%
(C) 0.2%
(D) 2%
(E) 20%
Arithmetic Percents
Since 0.01 ounce of water evaporated each day for
20 days, a total of 20(0.01) = 0.2 ounce evaporated.
en, to nd the percent of the original amount of
water that evaporated, divide the amount that
evaporated by the original amount and multiply
by 100 to convert the decimal to a percent. us,
0.2
10 100 0.02 100×= × or 2%.
e correct answer is D.
90. If m and p are positive integers and m2 + p2 < 100,
what is the greatest possible value of mp?
(A) 36
(B) 42
(C) 48
(D) 49
(E) 51
Arithmetic Operations with integers
Trying various integer values for m and
corresponding values of p that satisfy
m2+p2<100 might be the quickest way to solve
this problem. First, m<10 and p<10; otherwise,
m2+p2<100 is not true.
If m=9, then for m2+p2<100 to be true,
p<100 81−= 19, so p≤4, and the greatest
possible value for mp is (9)(4)=36.
Similarly, if m=8, then p<100 64−= 36, so
p≤5, and the greatest possible value for mp is
(8)(5)=40.
If m=7, then p<100 49−= 51, so p≤7, and
the greatest possible value for mp is (7)(7)=49.
If m=6, then p<100 36−= 64, so p≤7, and
the greatest possible value for mp is (6)(7)=42.
If m≤5 and p≤9, it follows that mp≤45.
us, the greatest possible value for mp is 49.
e correct answer is D.
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5.5 Problem Solving Answer Explanations
211
91. If = x
y
c
d
d
c
b
a
and==, which of the following must be
true?
=
=
=
y
x
b
a
x
a
y
b
y
a
x
b
I.
II.
III.
(A) I only
(B) II only
(C) I and II only
(D) I and III only
(E) I, II, and III
Algebra Ratio and proportion
Equation I is true:
x
y
c
d
= given
y
x
d
c
= take reciprocals
d
c
b
a
= given
y
x
b
a
= use last two equations
Equation II is true:
y
x
b
a
= Equation I (shown true)
ybx
a
= multiply both sides by x
y
b
x
a
= divide both sides by b
Equation III is false, since otherwise it would
follow that:
ybx
a
= from above
2
y
a
bx
a
= divide both sides by a
2
x
b
bx
a
= use Equation III (assumed true)
xbx
a
2
2
= multiply both sides by b
From this it follows that Equation III will hold
only if 1
2
2
b
a=, which can be false. For example,
if x = a = c = 1 and y = b = d = 2 (a choice of
values for which and
x
y
c
d
d
c
b
a
== are true), then
1
2
2
b
a≠ and Equation III is 2
1
1
2
=, which is false.
e correct answer is C.
92. If k is an integer and (0.0025)(0.025)(0.00025) × 10
k
is an integer, what is the least possible value of k ?
(A) –12
(B) –6
(C) 0
(D) 6
(E) 12
Arithmetic Properties of numbers
Let N = (0.0025)(0.025)(0.00025) × 10
k .
Rewriting each of the decimals as an
integer times a power of 10 gives
N = (25 × 10
−4 )(25 × 10
−3 )(25 × 10
−5 ) × 10
k =
(25)
3 × 10
k
− 12 . Since the units digit of (25)
3 is
5, it follows that if k = 11, then the tenths digit
of N would be 5, and thus N would not be an
integer; and if k = 12, then N would be
(25)
3 × 10
0 = (25)
3 , which is an integer. erefore,
the least value of k such that N is an integer is 12.
e correct answer is E.
93. If a ( a + 2) = 24 and b ( b + 2) = 24, where a ≠ b , then
a + b =
(A) –48
(B) –2
(C) 2
(D) 46
(E) 48
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Algebra Second-degree equations
a ( a + 2) =24 given
a
2 + 2 a = 24 use distributive property
a
2 + 2 a – 24 = 0 subtract 24 from both sides
( a + 6)( a – 4) = 0 factor
So, a + 6 = 0, which means that a = – 6, or
a – 4 = 0, which means a = 4. e equation with
the variable b has the same solutions, and so
b = – 6 or b = 4.
Since a ≠ b, then a = – 6 and b = 4, which means
a + b = − 6 + 4 = − 2, or a = 4 and b = − 6, which
means that a + b = 4 + ( − 6) = − 2
e correct answer is B.
94. In a recent election, Ms. Robbins received 8,000votes
cast by independent voters, that is, voters not
registered with a speci c political party. She also
received 10 percent of the votes cast by those voters
registered with a political party. If N is the total number
of votes cast in the election and 40 percent of the
votes cast were cast by independent voters, which of
the following represents the number of votes that Ms.
Robbins received?
(A) 0.06 N + 3,200
(B) 0.1 N + 7,200
(C) 0.4 N + 7,200
(D) 0.1 N + 8,000
(E) 0.06 N + 8,000
Algebra Percents
If N represents the total number of votes cast and
40% of the votes cast were cast by independent
voters, then 60% of the votes cast, or 0.6 N votes,
were cast by voters registered with a political
party. Ms. Robbins received 10% of these, and so
Ms. Robbins received (0.10)(0.6 N ) = 0.06 N votes
cast by voters registered with a political party.
us, Ms. Robbins received 0.06 N votes cast
by voters registered with a political party and
8,000votes cast by independent voters, so she
received 0.06 N + 8,000 votes in all.
e correct answer is E.
B
CA
95. In the gure shown, the triangle is inscribed in the
semicircle. If the length of line segment AB is 8 and the
length of line segment BC is 6, what is the length of
arc ABC ?
(A) 15π
(B) 12π
(C) 10π
(D) 7π
(E) 5π
Geometry Circles, triangles
Because ΔABC is inscribed in a semicircle,
∠ ABC is a right angle. Applying the Pythagorean
theorem gives ( AB )
2 + ( BC )
2 = ( AC )
2 . en
substituting the given lengths, 8
2 + 6
2 = ( AC )
2 ,
and so ( AC )
2 = 100 and AC = 10. us, the
diameter of the circle is 10, the circumference of
the entire circle is 10π, and the length of arc ABC
is half the circumference of the circle, or 5π.
e correct answer is E.
96. A manufacturer makes and sells 2products, P and Q.
The revenue from the sale of each unit of P is $20.00
and the revenue from the sale of each unit of Q is
$17.00. Last year the manufacturer sold twice as
many units of Q as P. What was the manufacturer’s
average (arithmetic mean) revenue per unit sold of
these 2products last year?
(A) $28.50
(B) $27.00
(C) $19.00
(D) $18.50
(E) $18.00
Arithmetic Statistics
Let x represent the number of units of ProductP
the manufacturer sold last year. en 2x
represents the number of units of ProductQ
the manufacturer sold last year, and x+2x=3x
represents the total number of units of ProductsP
and Q the manufacturer sold last year. e total
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5.5 Problem Solving Answer Explanations
213
revenue from the sale of ProductsP and Q was
$(20x)+$(17(2x))=$(54x), so the average
revenue per unit sold was $(54 )
3
x
x=$18.
e correct answer is E.
97. On a certain day, orangeade was made by mixing a
certain amount of orange juice with an equal amount
of water. On the next day, orangeade was made by
mixing the same amount of orange juice with twice
the amount of water. On both days, all the orangeade
that was made was sold. If the revenue from selling
the orangeade was the same for both days and if the
orangeade was sold at $0.60 per glass on the rst
day, what was the price per glass on the second day?
(A) $0.15
(B) $0.20
(C) $0.30
(D) $0.40
(E) $0.45
Arithmetic Applied problems
e ratio of the amount of orangeade made and
sold on the rst day to amount of orangeade
made and sold on the second day is 2:3, because
the orangeade on the rst day was 1 part orange
juice and 1 part water, while on the second day it
was 1 part orange juice and 2 parts water. us,
the ratio of the number of glasses of orangeade
made and sold on the rst day to the number of
glasses of orangeade made and sold on the second
day is 2:3. Since the revenues for each day were
equal and 2 glasses were sold on the rst day for
every 3 glasses that were sold on the second day,
2($0.60) = 3 p, where p represents the price per
glass at which the orangeade was sold on the
second day. erefore, 2
3$0.60 $0.40p
()
=⎛
⎝
⎜⎞
⎠
⎟=.
e correct answer is D.
98. A worker carries jugs of liquid soap from a production
line to a packing area, carrying 4 jugs per trip. If the
jugs are packed into cartons that hold 7 jugs each,
how many jugs are needed to ll the last partially lled
carton after the worker has made 17 trips?
(A) 1
(B) 2
(C) 4
(D) 5
(E) 6
Arithmetic Remainders
Carrying 4jugs per trip, the worker carries a
total of 4(17)=68jugs in 17 trips. At 7jugs per
carton, these jugs will completely ll 9cartons
with 5jugs left over since (9)(7)+5=68. To ll
the 10th carton, 7–5=2jugs are needed.
e correct answer is B.
w
w
99. The gure shown above represents a modern painting
that consists of four differently colored rectangles,
each of which has length ℓ and width w. If the area of
the painting is 4,800 square inches, what is the width,
in inches, of each of the four rectangles?
(A) 15
(B) 20
(C) 25
(D) 30
(E) 40
Geometry Area
From the gure, ℓ = 3 w , and the area of the
painting is ℓ( w + ℓ). Substituting 3 w for ℓ gives
3 w ( w + 3 w ) = 3 w (4 w ) = 12 w
2 . It is given that
the area is 4,800 square inches, so 12 w
2 = 4,800,
w
2 =400, and w = 20.
e correct answer is B.
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GMAT® Offi cial Guide 2018
214
100. A certain fruit stand sold apples for $0.70 each and
bananas for $0.50 each. If a customer purchased
both apples and bananas from the stand for a total of
$6.30, what total number of apples and bananas did
the customer purchase?
(A) 10
(B) 11
(C) 12
(D) 13
(E) 14
Algebra First-degree equations; Operations
with integers
If each apple sold for $0.70, each banana sold for
$0.50, and the total purchase price was $6.30, then
0.70 x + 0.50 y = 6.30, where x and y are positive
integers representing the number of apples and
bananas, respectively, the customer purchased.
0.70 x + 0.50 y = 6.30
0.50 y = 6.30 –0.70 x
0.50 y = 0.70(9– x )
y = 7
59x
()
−
Since y must be an integer, 9– x must be
divisible by 5. Furthermore, both x and y must be
positive integers. For x = 1, 2, 3, 4, 5, 6, 7, 8, the
corresponding values of 9– x are 8, 7, 6, 5, 4, 3, 2,
and 1. Only one of these, 5, is divisible by 5.
erefore, x = 4 and 7
594 7y
()
=−= and the
total number of apples and bananas the customer
purchased is 4 + 7 = 11.
e correct answer is B.
101. In the xy ‐plane, what is the slope of the line with
equation 3 x + 7 y = 9?
(A) 7
3
−
(B) 3
7
−
(C)
3
7
(D) 3
(E) 7
Algebra Coordinate geometry
Since the given equation of the line is equivalent
to 7 y = –3 x + 9, or 3
7
9
7
yx=− + , the slope of the
line is 3
7
−. Alternatively, choose 2 points lying on
the line and then use the slope formula for these
2 points. For example, substitute x = 0 in
7 y = –3 x + 9 and solve for y to get 0, 9
7
⎛
⎝
⎜⎞
⎠
⎟,
substitute y = 0 in 7 y = –3 x + 9 and solve for x
to get (3,0), then use the slope formula to get
−
−=−=−
9
70
03
9
7
3
3
7.
e correct answer is B.
102. Working simultaneously and independently at an
identical constant rate, 4machines of a certain type
can produce a total of x units of product P in 6days.
How many of these machines, working simultaneously
and independently at this constant rate, can produce a
total of 3 x units of productP in 4 days?
(A) 24
(B) 18
(C) 16
(D) 12
(E) 8
Algebra Applied problems
De ne a machine day as 1 machine working for
1 day. en, 4 machines each working 6 days is
equivalent to (4)(6) = 24 machine days. us,
x units of product P were produced in 24 machine
days, and 3 x units of product P will require
(3)(24) = 72machine days, which is equivalent
to 72
418= machines working independently and
simultaneously for 4 days.
e correct answer is B.
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5.5 Problem Solving Answer Explanations
215
103. At a certain school, the ratio of the number of second
graders to the number of fourth graders is 8 to 5, and
the ratio of the number of rst graders to the number
of second graders is 3 to 4. If the ratio of the number
of third graders to the number of fourth graders is 3
to 2, what is the ratio of the number of rst graders to
the number of third graders?
(A) 16 to 15
(B) 9 to 5
(C) 5 to 16
(D) 5 to 4
(E) 4 to 5
Arithmetic Ratio and proportion
If F , S , T , and R represent the number of rst,
second, third, and fourth graders, respectively,
then the given ratios are: (i) 8
5,ii 3
4
S
R
F
S
()
==
,
and iii 3
2
T
R
()
=. e desired ratio is F
T. From (i),
8
5
SR=, and from (ii), 3
4
FS=. Combining these
results, 3
4
3
4
8
5
6
5
FS R R==
⎛
⎝
⎜⎞
⎠
⎟=. From (iii),
===
⋅=TR F
T
R
R
3
2.Then
6
5
3
2
6
5
2
3
4
5. So, the
ratio of the number of rst graders to the number
of third graders is 4 to 5.
e correct answer is E.
104. The symbol Δ denotes one of the four arithmetic
operations: addition, subtraction, multiplication, or
division. If 6 Δ 3 ≤ 3, which of the following must be
true?
I. 2 Δ 2 = 0
II. 2 Δ 2 = 1
III. 4 Δ 2 = 2
(A) I only
(B) II only
(C) III only
(D) I and II only
(E) I, II, and III
Arithmetic Operations with integers
If Δ represents addition, subtraction,
multiplication, or division, then 6Δ3 is equal
to either 6+3=9, or 6–3=3, or 6×3=18,
or 6÷3=2. Since it is given that 6Δ3≤3, Δ
represents either subtraction or division.
Statement I is true for subtraction since 2–2=0
but not true for division since 2÷2=1.
Statement II is not true for subtraction since
2–2=0 but is true for division since 2÷2=1.
Statement III is true for subtraction since
4–2=2 and is true for division since 4÷2=2.
erefore, only Statement III must be true.
e correct answer is C.
105. The average distance between the Sun and a certain
planet is approximately 2.3× 10
14 inches. Which of the
following is closest to the average distance between
the Sun and the planet, in kilometers? (1 kilometer is
approximately 3.9 × 10
4 inches.)
(A) 7.1 × 10
8
(B) 5.9 × 10
9
(C) 1.6 × 10
10
(D) 1.6 × 10
11
(E) 5.9 × 10
11
Arithmetic Measurement conversion
Convert to kilometers and then estimate.
2.3 10 in 1km
3.9 10 in
2.3 10
3.9 10 km
2.3
3.9 10 km
2
410
0.5 10
510
14
4
14
4
14 4
10
10
9
()
××
⎛
⎝
⎜⎞
⎠
⎟=×
×
=×
≈×
=×
=×
−
e correct answer is B.
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GMAT® Offi cial Guide 2018
216
106. If mn ≠ 0 and 25 percent of n equals 371
2 percent of
m , what is the value of n
m
12 ?
(A) 18
(B)
32
3
(C) 8
(D) 3
(E)
9
8
Algebra Percents; First-degree equations
It is given that (25%) n =(37.5%) m , or
0.25 n =0.375 m . e value of 12n
m can be
found by rst nding the value of n
m and then
multiplying the result by 12. Doing this gives
12n
m=⎛
⎝
⎜⎞
⎠
⎟
0.375
0.25 (12)=18. Alternatively, the
numbers involved allow for a series of simple
equation transformations to be carried out, such
as the following:
0.25 n =0.375 m given
25 n =37.5 m multiply both sides by 100
50 n =75 m multiply both sides by 2
2 n =3 m divide both sides by 25
12 n =18 m multiply both sides by 6
12n
m=18 divide both sides by m
e correct answer is A.
107. In the coordinate plane, a circle has center (2,−3) and
passes through the point (5,0). What is the area of the
circle?
(A) 3π
(B)
32
π
(C)
33π
(D) 9π
(E) 18π
Geometry Coordinate geometry; Circles; Area
e area of a circle is given by π r
2 , where r is the
radius of the circle. e value of r
2 is the square
of the distance from the center to a point
of the circle. Using the distance formula,
r
2 = (2 − 5)
2 + (−3 − 0)
2 = 9 + 9 = 18. erefore,
the area of the circle is 18π.
e correct answer is E.
108. Last year Joe grew 1 inch and Sally grew 200percent
more than Joe grew. How many inches did Sally grow
last year?
(A) 0
(B) 1
(C) 2
(D) 3
(E) 4
Arithmetic Percents
Joe grew 1inch last year and Sally grew 200percent
more than Joe grew, so Sally grew 1inch plus
200percent of 1inch or 1+2(1)=3inches.
e correct answer is D.
109. The cost C , in dollars, to remove p percent of a certain
pollutant from a pond is estimated by using the formula
Cp
p
100,000
100
=−. According to this estimate, how much
more would it cost to remove 90 percent of the
pollutant from the pond than it would cost to remove
80 percent of the pollutant?
(A) $500,000
(B) $100,000
(C) $50,000
(D) $10,000
(E) $5,000
Algebra; Arithmetic Simplifying algebraic
expressions; Operations on rational numbers
Removing 90% of the pollutant from the pond
would cost
()()
−=
100, 000 90
100 90
9,000,000
10 =
900,000dollars, and removing 80% of the
pollutant would cost 100, 000 80
100 80
()()
−=
8,000,000
20 400, 000= dollars. e di erence is,
then, $900,000 − $400,000 = $500,000.
e correct answer is A.
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5.5 Problem Solving Answer Explanations
217
110. If xy ≠ 0 and x
2 y
2 – xy = 6, which of the following could
be y in terms of x ?
I. x
1
2
II. x
2
−
III.
x
3
(A) I only
(B) II only
(C) I and II
(D) I and III
(E) II and III
Algebra Second-degree equations
x
2 y
2 – xy = 6 given
x
2 y
2 – xy – 6 = 0 subtract 6 from both sides
( xy + 2)( xy – 3) = 0 factor
So, xy + 2 = 0, which means xy = – 2 and =−2
yx,
or xy – 3 = 0, which means that xy = 3 and
=3
yx. us, y in terms of x could be given by the
expressions in II or III.
e correct answer is E.
111. At a certain instant in time, the number of cars, N ,
traveling on a portion of a certain highway can be
estimated by the formula
NLd
s
20
600 2
=+
where L is the number of lanes in the same direction, d
is the length of the portion of the highway, in feet, and
s is the average speed of the cars, in miles per hour.
Based on the formula, what is the estimated number
of cars traveling on a 1
2 ‐ mile portion of the highway
if the highway has 2 lanes in the same direction and
the average speed of the cars is 40 miles per hour?
5,280 feet 1 mile
()
=
(A) 155
(B) 96
(C) 80
(D) 48
(E) 24
Algebra Simplifying algebraic expressions
Substitute
()
==2, 1
25, 280Ld , =40s into the
given formula and calculate the value for N .
()
()
()
()
()
=
⎛
⎝
⎜⎞
⎠
⎟
+
=+
=
=
=
=
20 2 1
25, 280
600 40
20 5, 280
600 1,600
20 5, 280
2, 200
2 528
22
528
11
48
2
N
e correct answer is D.
112. 4.8 109
× is closest in value to
(A) 2,200
(B) 70,000
(C) 220,000
(D) 7,000,000
(E) 22,000,000
Arithmetic Operations on radical expressions
ab a b
4.8 10 48 10 substitute 48 10
for 4.8 10
48 10
49 10 49 48
98 8
9
8
8
×=× ×
×
=× =×
≈× ≈
and then
49 10 7 10 49 7, 10
10 10
70, 000
84 8
424
()
×=× = =
=
=
e correct answer is B.
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GMAT® Offi cial Guide 2018
218
113. Three printing presses, R, S, and T, working together
at their respective constant rates, can do a certain
printing job in 4hours. SandT, working together at
their respective constant rates, can do the same job
in 5hours. How many hours would it take R, working
alone at its constant rate, to do the same job?
(A) 8
(B) 10
(C) 12
(D) 15
(E) 20
Algebra Applied problems
Let r be the portion of the job that printing
pressR, working alone, completes in 1hour;
and let s and t be the corresponding portions,
respectively, for printing pressS and printing
pressT. From the given information, it follows
that r + s + t =1
4 and s + t =1
5. Subtracting
these two equations gives r =−
1
4
1
5=1
20. It
follows that printing pressR, working alone, will
complete 1
20 of the job in 1hour, and therefore
printing pressR, working alone, will complete the
job in 20hours.
e correct answer is E.
114. For a party, three solid cheese balls with diameters of
2 inches, 4 inches, and 6 inches, respectively, were
combined to form a single cheese ball. What was the
approximate diameter, in inches, of the new cheese
ball? (The volume of a sphere is r
4
3
3
π
, where r is the
radius.)
(A) 12
(B) 16
(C) 16
3
(D)
38
3
(E)
236
3
Geometry Volume
Since the diameters of the cheese balls are given
as 2 inches, 4 inches, and 6inches, the radii of
the cheese balls are 1 inch, 2 inches, and 3 inches,
respectively. Using Vr
4
3
3
π
=, the combined
volume of the 3 cheese balls is 4
3123
333
π
()
++
or 4
3(36)
π
cubic inches.
us, if R represents the radius of the new cheese
ball, then the volume of the new cheese ball
is R
4
3
4
336
3
ππ
()
= and R
3 =36, from which
it follows that =36
3
Rinches. erefore,
the diameter of the new cheese ball is
2 R = 236
3 inches.
e correct answer is E.
115. The sum of all the integers k such that −26 < k < 24 is
(A) 0
(B) −2
(C) −25
(D) −49
(E) −51
Arithmetic Operations on integers
In the sum of all integers k such that
−26 < k < 24, the positive integers from 1 through
23 can be paired with the negative integers from
−1 through −23. e sum of these pairs is 0
because a + (− a ) = 0 for all integers a .
erefore, the sum of all integers k such that
−26 < k < 24 is −25 +(−24) + (23)(0) = −49.
e correct answer is D.
TSR
0
116. The number line shown contains three points R , S , and
T , whose coordinates have absolute values r , s , and t ,
respectively. Which of the following equals the average
(arithmetic mean) of the coordinates of the points R , S ,
and T ?
(A) s
(B) s + t − r
(C)
rst
3
−−
(D)
rst
3
++
(E)
str
3
+−
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5.5 Problem Solving Answer Explanations
219
Arithmetic Absolute value; Number line
Because point R is to the left of 0 on the number
line, the coordinate of R is negative. It is given
that r is the absolute value of the coordinate of R
and so the coordinate of R is − r . Because points
S and T are to the right of 0 on the number line,
their coordinates are positive. It is given that s
and t are the absolute values of the coordinates of
S and T , and so the coordinates of S and T are s
and t . e arithmetic mean of the coordinates of
R , S , and T is +−
3
str
.
e correct answer is E.
117. Mark and Ann together were allocated n boxes of
cookies to sell for a club project. Mark sold 10 boxes
less than n and Ann sold 2boxes less than n . If Mark
and Ann have each sold at least one box of cookies,
but together they have sold less than n boxes, what is
the value of n ?
(A) 11
(B) 12
(C) 13
(D) 14
(E) 15
Algebra Inequalities
Mark sold n −10 boxes and Ann sold n −2boxes.
Because each person sold at least one box, it
follows that n −10≥1 and n −2≥1, which
implies that n ≥11. On the other hand, together
they sold less than n boxes, so ( n −10)+( n −2) < n ,
which implies that n < 12. erefore, n is an
integer such that n ≥11 and n < 12, which
implies that n =11.
e correct answer is A.
118. A certain high school has 5,000 students. Of these
students, x are taking music, y are taking art, and z
are taking both music and art. How many students are
taking neither music nor art?
(A) 5,000 − z
(B) 5,000 − x − y
(C) 5,000 − x + z
(D) 5,000 − x − y − z
(E) 5,000 − x − y + z
Algebra Sets
Since x students are taking music, y students are
taking art, and z students are taking both music and
art, the number of students taking only music is
x − z , and the number of students taking only art is
y − z , as illustrated by the following Venn diagram.
x – z z y – z
artmusic
erefore, the number of students taking
neither music nor art is
5,000 − [( x − z ) + z + ( y − z )] = 5,000 − x − y + z .
e correct answer is E.
119. Yesterday’s closing prices of 2,420 different stocks
listed on a certain stock exchange were all different
from today’s closing prices. The number of stocks
that closed at a higher price today than yesterday was
20percent greater than the number that closed at a
lower price. How many of the stocks closed at a higher
price today than yesterday?
(A) 484
(B) 726
(C) 1,100
(D) 1,320
(E) 1,694
Arithmetic Percents
Let n be the number of stocks that closed at a
lower price today than yesterday. en 1.2 n is the
number of stocks that closed at a higher price
today than yesterday, and 1.2 n is the value asked
for. Because the total number of stocks is 2,420, it
follows that n + 1.2 n = 2,420, or 2.2 n = 2,420.
erefore, ==
2,420
2.2 1,100,n and hence
1.2 n = (1.2)(1,100) = 1,320.
e correct answer is D.
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GMAT® Offi cial Guide 2018
220
120. Each person who attended a company meeting was
either a stockholder in the company, an employee
of the company, or both. If 62 percent of those
who attended the meeting were stockholders and
47 percent were employees, what percent were
stockholders who were not employees?
(A) 34%
(B) 38%
(C) 45%
(D) 53%
(E) 62%
Arithmetic Sets
Let M represent the number of meeting
attendees. en, since 62% of M or 0.62 M were
stockholders and 47% of M or 0.47 M were
employees, it follows that 0.62 M + 0.47 M = 1.09 M
were either stockholders, employees, or both. Since
1.09 M exceeds M , the excess 1.09 M − M = 0.09 M
must be the number of attendees who were both
stockholders and employees, leaving the rest
0.62 M − 0.09 M = 0.53 M , or 53%, of the meeting
attendees to be stockholders but not employees.
e correct answer is D.
121. A gym class can be divided into 8 teams with an equal
number of players on each team or into 12 teams with
an equal number of players on each team. What is the
lowest possible number of students in the class?
(A) 20
(B) 24
(C) 36
(D) 48
(E) 96
Arithmetic Properties of numbers
e lowest value that can be divided evenly
by 8 and 12 is their least common multiple
(LCM). Since 8=2
3 and 12=2
2 (3), the LCM is
2
3 (3)=24.
e correct answer is B.
Accounts Amount Budgeted Amount Spent
Payroll $110,000 $117,000
Taxes 40,000 42,000
Insurance 2,500 2,340
122. The table shows the amount budgeted and the
amount spent for each of three accounts in a certain
company. For which of these accounts did the amount
spent differ from the amount budgeted by more than
6percent of the amount budgeted?
(A) Payroll only
(B) Taxes only
(C) Insurance only
(D) Payroll and Insurance
(E) Taxes and Insurance
Arithmetic Percents
For Payroll, 6% of the budgeted amount
is (0.06)($110,000)=$6,600. Since
$117,000–$110,000=$7,000>$6,600, the
amount spent di ered from the amount budgeted
by more than 6%.
For Taxes, 6% of the budgeted amount
is (0.06)($40,000)=$2,400. Since
$42,000–$40,000=$2,000<$2,400, the
amount spent did not di er from the amount
budgeted by more than 6%.
For Insurance, 6% of the budgeted
amount is (0.06)($2,500)=$150. Since
$2,500–$2,340=$160>$150, the amount
spent di ered from the amount budgeted by more
than 6%.
us, the amount spent di ered from the amount
budgeted by more than 6% for Payroll and
Insurance.
e correct answer is D.
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5.5 Problem Solving Answer Explanations
221
B
C
P
A
123. In the gure above, triangle ABC is equilateral, and point
P is equidistant from vertices A , B , and C . If triangle ABC
is rotated clockwise about point P , what is the minimum
number of degrees the triangle must be rotated so that
point B will be in the position where point A is now?
(A) 60
(B) 120
(C) 180
(D) 240
(E) 270
Geometry Angles
B
DC
P
A
Since Δ ABC is equilateral, the measure of
∠ ACB is 60°. erefore, the measure of
∠ BCD is 180° − 60° = 120°. Rotating the gure
clockwise about point P through an angle of 120°
will produce the gure shown below.
A
B
D
P
C
en rotating this gure clockwise about point P
through an angle of 120° will produce the gure
shown below.
C
A
D
P
B
In this gure, point B is in the position where
point A was in the original gure. e triangle
was rotated clockwise about point P through
120° + 120° = 240°.
e correct answer is D.
124. At least 2
3 of the 40 members of a committee must
vote in favor of a resolution for it to pass. What is the
greatest number of members who could vote against
the resolution and still have it pass?
(A) 19
(B) 17
(C) 16
(D) 14
(E) 13
Arithmetic Operations on rational numbers
If at least 2
3 of the members must vote in favor of
a resolution, then no more than 1
3 of the members
can be voting against it. On this 40‐member
committee,
1
3(40)=131
3, which means that no
more than 13 members can vote against the
resolution and still have it pass.
e correct answer is E.
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222
1
0
2
4
6
8
10
12
14
16
18
20
number of computers assembled
234
day
56
125. The graph shows the number of computers assembled
during each of 6consecutive days. From what day to
the next day was the percent change in the number of
computers assembled the greatest in magnitude?
(A) From Day1 to Day2
(B) From Day2 to Day3
(C) From Day3 to Day4
(D) From Day4 to Day5
(E) From Day5 to Day6
Arithmetic Percents
e following table shows the percent change
from each day to the next and the magnitude of
the percent change.
Time period Percent change Magnitude of percent change
From Day1 to Day2 12 20
20 100 % 8
20 100 % 40%
−×
⎛
⎝
⎜⎞
⎠
⎟=− ×
⎛
⎝
⎜⎞
⎠
⎟=− 40
From Day2 to Day3 18 12
12 100 % 6
12 100 % 50%
−×
⎛
⎝
⎜⎞
⎠
⎟=×
⎛
⎝
⎜⎞
⎠
⎟=50
From Day3 to Day4 10 18
18 100 % 8
18 100 % 44%
−×
⎛
⎝
⎜⎞
⎠
⎟=− ×
⎛
⎝
⎜⎞
⎠
⎟≈− 44
From Day4 to Day5 16 10
10 100 % 6
10 100 % 60%
−×
⎛
⎝
⎜⎞
⎠
⎟=×
⎛
⎝
⎜⎞
⎠
⎟=60
From Day5 to Day6 816
16 100 % 8
16 100 % 50%
−×
⎛
⎝
⎜
⎞
⎠
⎟=− ×
⎛
⎝
⎜⎞
⎠
⎟=− 50
e correct answer is D.
126. If n = 20! + 17, then n is divisible by which of the following?
I. 15
II. 17
III. 19
(A) None
(B) I only
(C) II only
(D) I and II
(E) II and III
Arithmetic Properties of numbers
Because 20! is the product of all integers from 1
through 20, it follows that 20! is divisible by each
integer from 1 through 20. In particular, 20! is
divisible by each of the integers 15, 17, and 19.
Since 20! and 17 are both divisible by 17, their
sum is divisible by 17, and hence the correct
answer will include II. If n were divisible by 15,
then n − 20! would be divisible by 15. But,
n − 20! = 17 and 17 is not divisible by 15.
erefore, the correct answer does not include I.
If n were divisible by 19, then n − 20! would be
divisible by 19. But, n − 20! = 17 and 17 is not
divisible by 19. erefore, the correct answer does
not include III.
e correct answer is C.
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5.5 Problem Solving Answer Explanations
223
127. The product of two negative numbers is 160. If the
lesser of the two numbers is 4 less than twice the
greater, what is the greater number?
(A) –20
(B) –16
(C) –10
(D) –8
(E) –4
Algebra Second-degree equations
Let x and y be the two numbers, where x is the
lesser of the two numbers and y is the number
desired. From the given information it follows
that xy =160 and x =2 y –4, from which it
follows that (2 y –4) y =160. Dividing both sides
of the last equation by 2 gives ( y –2) y =80. us,
80 is to be written as a product of two negative
numbers, one that is 2less than the other. Trying
simple factorizations of 80 quickly leads to the
value of y : (–40)(–2)=80, (–20)(–4)=80,
(–10)(–8)=80. erefore, y =–8. Note that
because –8 is one of the answer choices, it is not
necessary to ensure there are no other negative
solutions to the equation ( y –2) y =80.
Alternatively, ( y –2) y =80 can be written as
y
2 –2 y –80=0. Factoring the left side gives
( y +8)( y –10)=0, and y =–8 is the only negative
solution.
e correct answer is D.
128. According to a certain estimate, the depth N ( t ), in
centimeters, of the water in a certain tank at t hours past
2:00 in the morning is given by N ( t ) =−20( t − 5)
2 + 500
for 0 ≤ t ≤ 10. According to this estimate, at what time
in the morning does the depth of the water in the tank
reach its maximum?
(A) 5:30
(B) 7:00
(C) 7:30
(D) 8:00
(E) 9:00
Algebra Functions
When t = 5, the value of −20( t − 5)
2 + 500 is 500.
For all values of t between 0 and 10, inclusive,
except t = 5, the value of −20( t − 5)
2 is negative
and −20( t − 5)
2 + 500 < 500. erefore, the tank
reaches its maximum depth 5 hours after 2:00 in
the morning, which is 7:00 in the morning.
e correct answer is B.
129. After driving to a riverfront parking lot, Bob plans to run
south along the river, turn around, and return to the
parking lot, running north along the same path. After
running 3.25 miles south, he decides to run for only
50 minutes more. If Bob runs at a constant rate of
8 minutes per mile, how many miles farther south can
he run and still be able to return to the parking lot in
50minutes?
(A) 1.5
(B) 2.25
(C) 3.0
(D) 3.25
(E) 4.75
Algebra Applied problems
After running 3.25 miles south, Bob has been
running for
()
⎛
⎝
⎜⎞
⎠
⎟=3.25 miles 8 minutes
mile 26 minutes.
us, if t is the number of additional minutes
that Bob can run south before turning around,
then the number of minutes that Bob will run
north, after turning around, will be t + 26. Since
Bob will be running a total of 50minutes after
the initial 26 minutes of running, it follows that
t + ( t + 26) = 50, or t =12. erefore, Bob can
run south an additional 12 minutes
8minutes
mile
=1.5miles
before turning around.
e correct answer is A.
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130. Alex deposited x dollars into a new account that earned
8 percent annual interest, compounded annually. One
year later Alex deposited an additional x dollars into the
account. If there were no other transactions and if the
account contained w dollars at the end of two years,
which of the following expresses x in terms of w ?
(A) w
11.08+
(B) w
1.08 1.16+
(C) w
1.16 1.24+
(D) w
1.08 1.08 2
()
+
(E) w
1.08 1.08
23
()()
+
Algebra Applied problems
At the end of the rst year, the value of Alex’s
initial investment was x (1.08)dollars, and after he
deposited an additional x dollars into the account,
its value was [ x (1.08) + x ] dollars. At the end of
the second year, the value was w dollars, where
w =[ x (1.08) + x ](1.08) = x (1.08)
2 + x (1.08) =
x [(1.08)
2 + 1.08]. us,
()
=+1.08 1.08 2
xw.
e correct answer is D.
131. M is the sum of the reciprocals of the consecutive
integers from 201 to 300, inclusive. Which of the
following is true?
(A) M
1
3
1
2
<<
(B) M
1
5
1
3
<<
(C) M
1
7
1
5
<<
(D) M
1
9
1
7
<<
(E) M
1
12
1
9
<<
Arithmetic Estimation
Because 1
300 is less than each of the 99numbers
1
201 ,1
202 , ..., 1
299, it follows that
+++
1
300
1
300
1
300
(the sum of 99 identical
values) is less than +++
1
201
1
202
1
299
.
erefore, adding 1
300 to both sides of this last
inequality, it follows that +++
1
300
1
300
1
300
(the sum of 100 identical values) is less than
++++=
1
201
1
202
1
299
1
300 .M Hence,
()
⎛
⎝
⎜⎞
⎠
⎟<<100 1
300 or 1
3.MM Also, because
1
200 is greater than each of the 100 numbers
1
201 ,1
202 , ..., 1
300 , it follows that
+++
1
200
1
200
1
200
(the sum of 100 identical
values) is greater than +++
1
201
1
202
1
300
.
Hence,
()
⎛
⎝
⎜⎞
⎠
⎟>>100 1
200 or 1
2.MM
<>From 1
3and 1
2,MM it follows that
<<
1
3
1
2.M
e correct answer is A.
132. Working simultaneously at their respective constant
rates, Machines A and B produce 800 nails in x hours.
Working alone at its constant rate, Machine A produces
800 nails in y hours. In terms of x and y , how many
hours does it take Machine B , working alone at its
constant rate, to produce 800 nails?
(A) x
xy+
(B) y
xy+
(C) xy
xy+
(D) xy
xy−
(E) xy
yx−
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5.5 Problem Solving Answer Explanations
225
Algebra Applied problems
Let R
A and R
B be the constant rates, in nails
per hour, at which Machines A and B work,
respectively. en it follows from the given
information that R
A + R
B =800
x and R
A =800
y.
Hence, 800
y+ R
B =
800
x, or
R
B =−= −
⎛
⎝
⎜⎞
⎠
⎟=−
⎛
⎝
⎜⎞
⎠
⎟
800 800 800 11 800
xy xy
yx
xy .
erefore, the time, in hours, it would take
Machine B to produce 800 nails is given by
−
⎛
⎝
⎜⎞
⎠
⎟
=−
800
800 yx
xy
xy
yx
.
e correct answer is E.
133. In the Johnsons’ monthly budget, the dollar
amounts allocated to household expenses, food,
and miscellaneous items are in the ratio 5:2:1,
respectively. If the total amount allocated to these
three categories is $1,800, what is the amount
allocated to food?
(A) $900
(B) $720
(C) $675
(D) $450
(E) $225
Algebra Applied problems
Since the ratio is 5:2:1, let 5 x be the money
allocated to household expenses, 2 x be the money
allocated to food, and 1 x be the money allocated
to miscellaneous items. e given information can
then be expressed in the following equation and
solved for x .
++=
=
=
5 2 1 $1,800
8 $1,800 combine like terms
$225 divide both sides by 8
xxx
x
x
e money allocated to food is
2 x =2($225)=$450.
e correct answer is D.
Number of
Marbles in
Each of Three
Bags
Percent of Marbles
in Each Bag That Are
Blue (to the nearest
tenth)
Bag P 37 10.8%
Bag Q ×66.7%
Bag R 32 50.0%
134. If 1
3 of the total number of marbles in the three bags
listed in the table above are blue, how many marbles
are there in bag Q ?
(A) 5
(B) 9
(C) 12
(D) 23
(E) 46
Algebra Percents
What is the value of x , the number of marbles
in bag Q ? From the given information and
rounded to the nearest integer, bag P has
(37)(0.108)=4blue marbles, bag Q has
( x )(0.667)=2
3 x blue marbles, and bag R has
(32)(0.5)=16blue marbles. erefore, the total
number of blue marbles is equal to
4+2
3 x +16=20+2
3 x . It is given that 1
3 of the
total number of marbles are blue, so the total
number of blue marbles is also equal to
1
3(37+ x +32)=1
3 x +23. It follows that
20+2
3 x =1
3 x +23, or 1
3 x =3, or x =9.
e correct answer is B.
135. 0.0036 2.8
0.04 0.1 0.003
()()
()()( )
=
(A) 840.0
(B) 84.0
(C) 8.4
(D) 0.84
(E) 0.084
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Arithmetic Operations with rational numbers
To make the calculations less tedious, convert the
decimals to whole numbers times powers of 10 as
follows:
()()
()()( )
0.0036 2.8
0.04 0.1 0.003
()()
()()()
()()
()()()
()()
()()()
()()
()()()
=××
×××
=×
=×
=×
()( )
()
−−
−−−
−− −−− −
−−−
−+
36 10 28 10
4 10 1 10 3 10
36 28
413 10
36 28
413 10
36 28
413 10
41
213
41 213
56
56
()()
=⎛
⎝
⎜⎞
⎠
⎟⎛
⎝
⎜⎞
⎠
⎟×
=×
=×
=
−+
36
3
28
410
12 7 10
84 10
840
56
1
e correct answer is A.
136. If n is an integer greater than 6, which of the following
must be divisible by 3?
(A) nn n14
()( )
+−
(B) nn n21
()
()
+−
(C) nn n35
()
()
+−
(D) nn n42
()
()
+−
(E) nn n56
()
()
+−
Arithmetic Properties of numbers
e easiest and quickest way to do this problem is
to choose an integer greater than 6, such as 7, and
eliminate answer choices in which the value of
the expression is not divisible by 3:
A
()()()()()
+−=77174 783, which is
divisible by 3, so A cannot be eliminated.
B
( )( ) ()()()
+−=77 271 796, which is
divisible by 3, so B cannot be eliminated.
C
()
() ()()()
+−=77 3 7 5 7 10 2,
which is not
divisible by 3, so C can be eliminated.
D
()
()()()()
+−=77 4 7 2 7 11 5, which is not
divisible by 3, so D can be eliminated.
E
()
()()()()
+−=77 5 7 6 7 12 1,
which is
divisible by 3, so E cannot be eliminated.
Choose another integer greater than 6, such as 8,
and test the remaining answer choices:
A
()()()()()
+−=
8
8184 894, which is
divisible by 3, so A cannot be eliminated.
B
()()()()()
+−=
8
8281 8107, which is not
divisible by 3, so B can be eliminated.
E
()
()()()()
+−=
8
8586 8132, which is not
divisible by 3, so E can be eliminated.
us, A is the only answer choice that has not
been eliminated.
For the more mathematically inclined, if n is
divisible by 3, then the expression in each answer
choice is divisible by 3. Assume, then, that n is
not divisible by 3. If the remainder when n is
divided by 3 is 1, then n =3 q +1 for some integer
q . All of the expressions n – 4, n – 1, n + 2, and
n + 5 are divisible by 3 [i.e., n – 4 = 3 q – 3 = 3( q – 1),
n – 1 = 3 q , n + 2 = 3 q + 3 = 3( q + 1),
n + 5 = 3 q + 6 = 3( q + 2)], and none of the
expressions n – 6, n – 5, n – 2, n + 1, n + 3, and
n + 4 is divisible by 3. erefore, if the remainder
when n is divided by 3 is 1, only the expressions
in answer choices A, B, and E are divisible by 3.
On the other hand, if the remainder when n is
divided by 3 is 2, then n = 3 q + 2 for some integer q .
All of the expressions n – 5, n – 2, n + 1, and
n + 4 are divisible by 3 [i.e., n – 5 = 3 q – 3 = 3( q – 1),
n – 2 = 3 q , n + 1 = 3 q + 3 = 3( q + 1),
n +4 = 3 q + 6 = 3( q + 2)], and none of the
expressions n – 6, n – 4, n – 1, n + 2, n + 3, and
n + 5 is divisible by 3. erefore, if the remainder
when n is divided by 3 is 2, only the expressions
in answer choices A, C, and D are divisible by
3. Only the expression in answer choice A is
divisible by 3 regardless of whether n is divisible
by 3, has a remainder of 1 when divided by 3, or
has a remainder of 2 when divided by 3.
e correct answer is A.
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5.5 Problem Solving Answer Explanations
227
Age Category
(in years)
Number of
Employees
Less than 20 29
20–29 58
30–39 36
40–49 21
50–59 10
60–69 5
70 and over 2
137. The table above gives the age categories of the
161employees at Company X and the number of
employees in each category. According to the table,
if m is the median age, in years, of the employees at
CompanyX, then m must satisfy which of the following?
(A) 20 ≤ m ≤ 29
(B) 25 ≤ m ≤ 34
(C) 30 ≤ m ≤ 39
(D) 35 ≤ m ≤ 44
(E) 40 ≤ m ≤ 49
Arithmetic Statistics
e median of 161ages is the 81stage when the
ages are listed in order. Since 29 of the ages are
less than 20, the median age must be greater than
or equal to 20. Since 58 of the ages are between
20 and 29, a total of 29+58=87 of the ages are
less than or equal to 29, and thus the median age
is less than or equal to 29. erefore, the median
age is greater than or equal to 20 and less than or
equal to 29.
e correct answer is A.
138. If x and y are positive numbers such that x + y = 1,
which of the following could be the value of
100 x + 200 y ?
I. 80
II. 140
III. 199
(A) II only
(B) III only
(C) I and II
(D) I and III
(E) II and III
Algebra Simultaneous equations; Inequalities
Since x + y = 1, then y = 1 − x and 100 x + 200 y
can be expressed as 100 x + 200(1 − x ) = 200 − 100 x .
Test each value.
I. If 200 − 100 x = 80, then x = −200 80
100 =1.2
and y = 1 − 1.2 = −0.2.
Since y must be positive, 80 cannot be a
value of 100 x + 200 y .
II. If 200 − 100 x = 140, then x = −200 140
100 =0.6
and y =1−0.6=0.4, so 140 can be a value
of 100 x + 200 y .
III. If 200 − 100 x = 199, then x = −200 199
100 =0.01
and y = 1 − 0.01 = 0.99, so 199 can be a
value of 100 x + 200 y .
e correct answer is E.
139. If X is the hundredths digit in the decimal 0.1X and if
Y is the thousandths digit in the decimal 0.02Y, where
X and Y are nonzero digits, which of the following is
closest to the greatest possible value of X
Y
0.1
0.02 ?
(A) 4
(B) 5
(C) 6
(D) 9
(E) 10
Arithmetic Operations with decimals; Place
value
e greatest possible value of 0.1
0.02
X
Y will occur
when 0.1X has the greatest possible value and
0.02Y has the least possible value. Since X and
Y are nonzero digits, this means than X must be
9 and Y must be 1. e greatest possible value of
0.1
0.02
X
Y is then 0.19
0.021≈9.05, which is closest to 9.
e correct answer is D.
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140. Clarissa will create her summer reading list by
randomly choosing 4books from the 10books
approved for summer reading. She will list the books in
the order in which they are chosen. How many different
lists are possible?
(A) 6
(B) 40
(C) 210
(D) 5,040
(E) 151,200
Arithmetic Elementary combinatorics
Any of the 10books can be listed rst. Any of the
9books remaining after the rst book is listed can
be listed second. Any of the 8books remaining
after the rst and second books are listed can be
listed third. Any of the 7books remaining after
the rst, second, and third books are listed can
be listed fourth. By the multiplication principle,
there are (10)(9)(8)(7)=5,040di erent lists
possible.
e correct answer is D.
141. If n is a positive integer and the product of all the
integers from 1 to n , inclusive, is divisible by 990,
what is the least possible value of n ?
(A) 8
(B) 9
(C) 10
(D) 11
(E) 12
Arithmetic Properties of numbers
For convenience, let N represent the product of
all integers from 1 through n . en, since N is
divisible by 990, every prime factor of 990 must
also be a factor of N . e prime factorization of
990 is 2 × 3
2 × 5 × 11, and therefore, 11 must be
a factor of N . en, the least possible value of N
with factors of 2, 5, 3
2 , and 11 is 1 × 2 × 3 × … × 11,
and the least possible value of n is 11.
e correct answer is D.
142. The probability that event M will not occur is 0.8 and the
probability that event R will not occur is 0.6. If events M
and R cannot both occur, which of the following is the
probability that either event M or event R will occur?
(A)
1
5
(B)
2
5
(C)
3
5
(D)
4
5
(E)
12
25
Arithmetic Probability
Let P ( M ) be the probability that event M
will occur, let P ( R ) be the probability that
event R will occur, and let P ( M and R ) be the
probability that events M and R both occur.
en the probability that either event M or
event R will occur is P ( M )+ P ( R )– P ( M and R ).
From the given information, it follows that
P ( M )=1.0–0.8=0.2, P ( R )=1.0–0.6=0.4,
and P ( M and R )=0. erefore, the probability
that either event M or event R will occur is
0.2+0.4–0=0.6=3
5.
e correct answer is C.
143. The total cost for Company X to produce a batch of
tools is $10,000 plus $3 per tool. Each tool sells for
$8. The gross pro t earned from producing and selling
these tools is the total income from sales minus the total
production cost. If a batch of 20,000 tools is produced
and sold, then Company X’s gross pro t per tool is
(A) $3.00
(B) $3.75
(C) $4.50
(D) $5.00
(E) $5.50
Arithmetic Applied problems
e total cost to produce 20,000 tools is
$10,000 + $3(20,000) = $70,000. e revenue
resulting from the sale of 20,000 tools is
$8(20,000) = $160,000. e gross pro t is
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5.5 Problem Solving Answer Explanations
229
$160,000 – $70,000 = $90,000, and the gross
pro t per tool is $90, 000
20, 000 =$4.50.
e correct answer is C.
144. If Q is an odd number and the median of Q consecutive
integers is 120, what is the largest of these integers?
(A)
Q1
2
−+120
(B)
Q
2+119
(C)
Q
2+120
(D)
Q119
2
+
(E)
Q120
2
+
Arithmetic Statistics
For an odd number of data values, the median
is the middle number. us, 120 is the middle
number, and so half of the Q − 1 remaining values
are at most 120 and the other half of the Q − 1
remaining values are at least 120. In particular,
−1
2
Q data values lie to the right of 120 when
the data values are listed in increasing order
from left to right, and so the largest data value
is 120+−1
2
Q. Alternatively, it is evident that
(B), (C), or (E) cannot be correct since these
expressions do not have an integer value when
Q is odd. For the list consisting of the single
number 120 (i.e., if Q = 1), (D) fails because
+=+119
2
1 119
2
Q=60≠120 and (A) does not
fail because −1
2
Q+120=−11
2+120=120.
e correct answer is A.
145. A ladder of a re truck is elevated to an angle of 60°
and extended to a length of 70 feet. If the base of
the ladder is 7 feet above the ground, how many feet
above the ground does the ladder reach?
(A) 35
(B) 42
(C)
35 3
(D)
7353+
(E)
7423+
Geometry Triangles
C
ground 7 feet
70 feet
60°
AB
Given the gure above, determine BC . en add
7 to determine how far above the ground the
ladder reaches.
Triangle Δ ABC is a 30°−60°−90° triangle with
hypotenuse
AC of length 70 feet. Since the lengths
of the sides of a 30°−60°−90° triangle are in the
ratio 1:2: 3, =1
2
AB
AC and so AB =1
2 AC =35,
and AB
BC =1
3 and so BC = AB 3=35 3.
erefore, the ladder reaches +7353 feet above
the ground.
e correct answer is D.
4 ft
10 ft
146. The window in the gure above consists of a rectangle
and a semicircle with dimensions as shown. What is
the area, in square feet, of the window?
(A) 40 + 8π
(B) 40 + 2π
(C) 32 + 8π
(D) 32 + 4π
(E) 32 + 2π
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Geometry Area
e semicircle has a radius of 2ft, and thus its area
is 1
2π(2
2 )=2πft
2 . e rectangle has dimensions
4ft by 8ft, where 8=10−2 is the full height of
the window minus the radius of the semicircle,
and thus has area (4)(8)=32ft
2 . erefore, in
square feet, the area of the window is 32+2π.
e correct answer is E.
147. If there are fewer than 8 zeros between the decimal
point and the rst nonzero digit in the decimal
expansion of t
1,000
4
⎛
⎝
⎜⎞
⎠
⎟, which of the following
numbers could be the value of t ?
I. 3
II. 5
III. 9
(A) None
(B) I only
(C) II only
(D) III only
(E) II and III
Arithmetic Properties of numbers; Decimals
e decimal expansion of ⎛
⎝
⎜⎞
⎠
⎟
1
1,000
4
=10
–12
has 11zeros to the right of the decimal point
followed by a single digit that is 1. erefore, in
the decimal expansion of ⎛
⎝
⎜⎞
⎠
⎟
1,000
4
t= t
4 ×10
–12 ,
the number of zeros between the decimal point
and the rst nonzero digit is equal to 12 minus
the number of digits in the integer t
4 . Since this
number of zeros is fewer than 8, it follows that
the number of digits in the integer t
4 is greater
than 4. e integer t cannot be 3, because the
number of digits in 3
4 =81 is not greater than 4.
e integer t cannot be 5, because the number
of digits in 5
4 =625 is not greater than 4. e
integer t cannot be 9, because the number of digits
in 9
4 =6,561 is not greater than 4. erefore, none
of 3, 5, or 9 could be the value of t .
e correct answer is A.
148. A three‐digit code for certain locks uses the digits 0,
1, 2, 3, 4, 5, 6, 7, 8, 9 according to the following
constraints. The rst digit cannot be 0 or 1, the
second digit must be 0 or 1, and the second and third
digits cannot both be 0 in the same code. How many
different codes are possible?
(A) 144
(B) 152
(C) 160
(D) 168
(E) 176
Arithmetic Elementary combinatorics
Since the rst digit cannot be 0 or 1, there are 8
digits possible for the rst digit. Since the second
digit must be 0 or 1, there are 2 digits possible
for the second digit. If there were no other
restrictions, all 10 digits would be possible for the
third digit, making the total number of possible
codes 8 × 2 × 10 = 160. But, the additional
restriction that the second and third digits cannot
both be 0 in the same code eliminates the 8 codes
2‐0‐0, 3‐0‐0, 4‐0‐0, 5‐0‐0, 6‐0‐0, 7‐0‐0, 8‐0‐0,
and 9‐0‐0. erefore, there are 160 − 8 = 152
possible codes.
e correct answer is B.
149. Jackie has two solutions that are 2 percent sulfuric
acid and 12 percent sulfuric acid by volume,
respectively. If these solutions are mixed in appropriate
quantities to produce 60 liters of a solution that is
5 percent sulfuric acid, approximately how many liters
of the 2 percent solution will be required?
(A) 18
(B) 20
(C) 24
(D) 36
(E) 42
Algebra Simultaneous equations
Let x represent the quantity of the 2% sulfuric
acid solution in the mixture, from which it follows
that the 2% sulfuric acid solution contributes
0.02 x liters of sulfuric acid to the mixture. Let y
represent the quantity of the 12% sulfuric acid
solution in the mixture, from which it follows
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5.5 Problem Solving Answer Explanations
231
that the 12% sulfuric acid solution contributes
0.12 y liters of sulfuric acid to the mixture. Since
there are 60 liters of the mixture, x + y = 60. e
quantity of sulfuric acid in the mixture, which
is 5% sulfuric acid, is then (0.05)(60) = 3 liters.
erefore, 0.02 x + 0.12 y = 3. Substituting 60 − x
for y gives 0.02 x + 0.12(60 − x ) = 3. en,
0.02 0.12 60 3
0.02 7.2 0.12 3
7.2 0.1 3
0.1 4.2
42
given
use distributive
property
combine like terms
subtract 7.2 from
both sides
divide both sides
by 0.1
xx
xx
x
x
x
()
+−=
+− =
−=
−=−
=
−
e correct answer is E.
150. If Jake loses 8 pounds, he will weigh twice as much as
his sister. Together they now weigh 278 pounds. What
is Jake’s present weight, in pounds?
(A) 131
(B) 135
(C) 139
(D) 147
(E) 188
Algebra Systems of equations
Let J represent Jake’s weight and S represent his
sister’s weight. en J − 8 = 2 S and J + S = 278.
Solve the second equation for S and get
S = 278 − J. Substituting the expression for S into
the rst equation gives
−= −
−= −
+= +
=
=
8 2(278 )
8 556 2
2 556 8
3 564
188
JJ
JJ
JJ
J
J
e correct answer is E.
151. For each student in a certain class, a teacher adjusted
the student’s test score using the formula y=0.8x+20,
where x is the student’s original test score and y is the
student’s adjusted test score. If the standard deviation of
the original test scores of the students in the class was
20, what was the standard deviation of the adjusted test
scores of the students in the class?
(A) 12
(B) 16
(C) 28
(D) 36
(E) 40
Arithmetic Statistics
Let n be the number of students in the class, let
x
n
μ=∑ be the mean of the students’ unadjusted
scores. It follows that the standard deviation
of the unadjusted scores is 20 .
2
x
n
()
=−μ
∑
To nd the standard deviation of the
adjusted scores, rst nd their mean:
(0.8 20) 0.8 20 0.8 20.
x
n
x
n
n
n
+
∑=∑+=μ+ en,
subtract the adjusted mean from each adjusted
score: (0.8x+20)–(0.8μ+20)=0.8(x–μ). Next,
square each di erence: (0.8(x–μ))2=0.64(x–μ)2.
Next, nd the average of the squared
di erences: 0.64 0.64 .
22
x
n
x
n
() ()
−μ
∑=−μ
∑
Finally, take the nonnegative square root:
0.64 0.8 0.8 20 16.
22
x
n
x
n
() ()
()
−μ
∑=−μ
∑==
e correct answer is B.
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GMAT® Offi cial Guide 2018
232
152. Last year 26 members of a certain club traveled
to England, 26 members traveled to France, and
32members traveled to Italy. Last year no members
of the club traveled to both England and France,
6members traveled to both England and Italy, and
11members traveled to both France and Italy. How
many members of the club traveled to at least one of
these three countries last year?
(A) 52
(B) 67
(C) 71
(D) 73
(E) 79
Arithmetic Applied problems
e numbers in the following diagram represent
the numbers of members of the club who
traveled to the indicated countries, and these
numbers can be determined as follows. Since no
members traveled to both England and France,
both regions that form the overlap of England
and France are labeled with 0. It follows that
none of the 6members who traveled to both
England and Italy traveled to France, and so
the region corresponding to England and Italy
only is labeled with 6. It also follows that none
of the 11members who traveled to both France
and Italy traveled to England, and so the region
corresponding to France and Italy only is labeled
with 11. At this point it can be determined that
26–6=20members traveled to England only,
26–11=15members traveled to France only, and
32–(6+11)=15members traveled to Italy only.
15
France
Italy
England
0
0
15
116
20
From the diagram it follows that
20+15+6+11+15=67 members traveled to
at least one of these three countries.
e correct answer is B.
153. A store reported total sales of $385 million for
February of this year. If the total sales for the same
month last year was $320 million, approximately what
was the percent increase in sales?
(A) 2%
(B) 17%
(C) 20%
(D) 65%
(E) 83%
Arithmetic Percents
e percent increase in sales from last year to this
year is 100 times the quotient of the di erence
in sales for the two years divided by the sales last
year. us, the percent increase is
385 320
320 100 65
320 100
13
64 100
13
65 100
1
5100
20%
−×= ×
=×
≈×
=×
=
e correct answer is C.
154. When positive integer x is divided by positive integer y ,
the remainder is 9. If x
y=96.12, what is the value
of y ?
(A) 96
(B) 75
(C) 48
(D) 25
(E) 12
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5.5 Problem Solving Answer Explanations
233
Arithmetic Properties of numbers
e remainder is 9 when x is divided by y ,
so x = yq + 9 for some positive integer q .
Dividing both sides by y gives =+
9x
yqy.
But, ==+96.12 96 0.12
x
y. Equating the two
expressions for x
y gives += +
996 0.12qy.
us, q = 96 and =
90.12
y.
=
=
=
90.12
9
0.12
75
y
y
y
e correct answer is B.
155. If x (2 x +1)=0 and x1
2
+⎞
⎠
⎟
⎛
⎝
⎜(2 x –3)=0, then x =
(A) −3
(B) 1
2
−
(C) 0
(D) 1
2
(E) 3
2
Algebra Second-degree equations;
Simultaneous equations
Setting each factor equal to 0, it can be seen that
the solution set to the rst equation is 0, 1
2
−
⎧
⎨
⎩
⎫
⎬
⎭
and the solution set to the second equation is
1
2,3
2
−
⎧
⎨
⎩
⎫
⎬
⎭. erefore, 1
2
− is the solution to both
equations.
e correct answer is B.
XY
156. Figures X and Y above show how eight identical
triangular pieces of cardboard were used to form a
square and a rectangle, respectively. What is the ratio
of the perimeter of X to the perimeter of Y ?
(A) 2:3
(B) 2:2
(C) 2 2:3
(D) 1:1
(E) 2 :1
Geometry Perimeter
Because Figure X is a square and the
diagonals of a square are the same length, are
perpendicular, and bisect each other, it follows
that each triangular piece is a 45°−45°−90°
triangle. us, the length of each side of the
square is a 2 , and the perimeter is 4 a 2 . e
perimeter of the rectangle is 2( a + 2 a ) = 6 a .
It follows that the ratio of the perimeter of
the square to the perimeter of the rectangle is
42
6
22
3,or2 2:3.
a
a=
e correct answer is C.
157. A certain experimental mathematics program was tried
out in 2 classes in each of 32 elementary schools
and involved 37teachers. Each of the classes had
1teacher and each of the teachers taught at least 1,
but not more than 3, of the classes. If the number of
teachers who taught 3 classes is n , then the least and
greatest possible values of n , respectively, are
(A) 0 and 13
(B) 0 and 14
(C) 1 and 10
(D) 1 and 9
(E) 2 and 8
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GMAT® Offi cial Guide 2018
234
Algebra Simultaneous equations; Inequalities
It is given that 2(32)=64classes are taught
by 37teachers. Let k , m , and n be the number
of teachers who taught, respectively, 1, 2,
and 3 of the classes. en k + m + n =37
and k +2 m +3 n =64. Subtracting these two
equations gives m +2 n =64–37=27, or
2 n =27– m , and therefore 2 n ≤27. Because n is
an integer, it follows that n ≤13 and B cannot
be the answer. Since n =0 is possible, which can
be seen by using m =27 and k =10 (obtained by
solving 2 n =27– m with n =0, then by solving
k + m + n =37 with n =0 and m =27), the
answer must be A.
It is not necessary to ensure that n =13 is
possible to answer the question. However, it is
not di cult to see that k =23, m =1, and n =13
satisfy the given conditions.
e correct answer is A.
158. For the positive numbers, n , n + 1, n + 2, n + 4, and
n + 8, the mean is how much greater than the median?
(A) 0
(B) 1
(C) n + 1
(D) n + 2
(E) n + 3
Algebra Statistics
Since the ve positive numbers n , n + 1, n +2,
n + 4, and n + 8 are in ascending order, the
median is the third number, which is n + 2. e
mean of the ve numbers is
( 1)( 2)( 4)( 8)
5
515
5
3
nnnnn
n
n
++++++++
=+
=+
Since (3)(2)1nn+−+=, the mean is 1 greater
than the median.
e correct answer is B.
159. The interior of a rectangular carton is designed by a
certain manufacturer to have a volume of x cubic feet
and a ratio of length to width to height of 3:2:2. In
terms of x , which of the following equals the height of
the carton, in feet?
(A) x
3
(B) x2
3
3
(C) x3
2
3
(D) x
2
3
3
(E) x
3
2
3
Geometry; Arithmetic Volume; Ratio and
proportion
Letting c represent the constant of
proportionality, the length, width, and height,
in feet, of the carton can be expressed as 3 c , 2 c ,
and 2 c , respectively. e volume of the carton is
then (3 c )(2 c )(2 c ) = 12 c
3 cubic feet. But, the
volume is x cubic feet, and so 12 c
3 = x . en,
c
3 = 12
x and c = 12
3x. e height of the carton is 2 c
and in terms of x , 2 c = 2 12
3x. Since 2=8
3 and
33 3
ab ab
()()
=, the height of the carton can be
expressed as 212 812
2
3.
333
xxx
=⎛
⎝
⎜⎞
⎠
⎟=
e correct answer is B.
160. The present ratio of students to teachers at a certain
school is 30 to 1. If the student enrollment were to
increase by 50 students and the number of teachers
were to increase by 5, the ratio of students to
teachers would then be 25 to 1. What is the present
number of teachers?
(A) 5
(B) 8
(C) 10
(D) 12
(E) 15
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5.5 Problem Solving Answer Explanations
235
Algebra Applied problems
Let s be the present number of students, and let t
be the present number of teachers. According to
the problem, the following two equations apply:
30
1=s
tCurrent student to teacher ratio
50
5
s
t
+
+=25
1Future student to teacher ratio
Solving the rst equation for s gives s = 30 t.
Substitute this value of s into the second
equation, and solve for t .
30 50
5
t
t
+
+=25
1
30 50t+=25 125t+multiply both sides by 5t+
5t=75 simplify by subtraction
t =15
e correct answer is E.
161. What is the smallest integer n for which 25 5
n12
>?
(A) 6
(B) 7
(C) 8
(D) 9
(E) 10
Arithmetic Operations with rational numbers
Because 525
2=, a common base is 5. Rewrite
the left side with 5 as a base: 25 (5 ) 5
22nnn
==. It
follows that the desired integer is the least integer
n for which 55
212n>. is will be the least
integer n for which 212n>, or the least integer n
for which n > 6, which is 7.
e correct answer is B.
162. Sixty percent of the members of a study group are
women, and 45percent of those women are lawyers.
If one member of the study group is to be selected
at random, what is the probability that the member
selected is a woman lawyer?
(A) 0.10
(B) 0.15
(C) 0.27
(D) 0.33
(E) 0.45
Arithmetic Probability
For simplicity, suppose there are 100 members in
the study group. Since 60percent of the members
are women, there are 60 women in the group.
Also, 45percent of the women are lawyers so
there are 0.45(60) = 27 women lawyers in the
study group. erefore the probability of selecting
a woman lawyer is 27
100 =0.27.
e correct answer is C.
163. Each year for 4 years, a farmer increased the number
of trees in a certain orchard by 1
4 of the number of
trees in the orchard the preceding year. If all of the
trees thrived and there were 6,250 trees in the orchard
at the end of the 4‐year period, how many trees were
in the orchard at the beginning of the 4‐year period?
(A) 1,250
(B) 1,563
(C) 2,250
(D) 2,560
(E) 2,752
Arithmetic Operations on rational numbers
Increasing the number of trees each year by 1
4 of
the number of trees in the orchard the preceding
year is equivalent to making the number of trees
increase 25% per year, compounded yearly. If
there were n trees at the beginning of the 4‐year
period, then there will be 1.25 n trees at the end of
the rst year, 1.25(1.25 n ) = (1.25)
2 n trees at the
end of the second year, 1.25[(1.25)
2 n ] = (1.25)
3 n
trees at the end of the third year, and
1.25[(1.25)
3 n ] = (1.25)
4 n trees at the end of the
fourth year. Hence, 6,250 = (1.25)
4 n and
n = 6, 250
(1.25)4. e arithmetic can be greatly
simpli ed by rewriting (1.25)
4 as 5
4
5
4
44
4
⎛
⎝
⎜⎞
⎠
⎟=
and 6,250 as (625)(10) = (5
4 )(10). en
6,250
(1.25) (5 )(10) 4
5(10)(4 ) 2,560
4
44
4
4
=⎛
⎝
⎜⎞
⎠
⎟==.
e correct answer is D.
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GMAT® Offi cial Guide 2018
236
400,000
300,000
200,000
100,000
0
number of shipments
1990 1992 1994 1996 1998 2000
year
Number of Shipments of Manufactured Homes
in the United States, 1990–2000
164. According to the chart shown, which of the following is
closest to the median annual number of shipments of
manufactured homes in the United States for the years
from 1990 to 2000, inclusive?
(A) 250,000
(B) 280,000
(C) 310,000
(D) 325,000
(E) 340,000
Arithmetic Interpretation of graphs and
tables; Statistics
From the chart, the approximate numbers of
shipments are as follows:
Year Number of shipments
1990 190,000
1991 180,000
1992 210,000
1993 270,000
1994 310,000
1995 350,000
1996 380,000
1997 370,000
1998 390,000
1999 360,000
2000 270,000
Since there are 11 entries in the table and 11 is
an odd number, the median of the numbers of
shipments is the 6th entry when the numbers
of shipments are arranged in order from least to
greatest. In order, from least to greatest, the rst 6
entries are:
Number of shipments
180,000
190,000
210,000
270,000
270,000
310,000
e 6th entry is 310,000.
e correct answer is C.
165. For the positive integers a , b , and k , ab
k means that
ak is a divisor of b , but ak1+ is not a divisor of b . If k is
a positive integer and 272,
k then k is equal to
(A) 2
(B) 3
(C) 4
(D) 8
(E) 18
Arithmetic Property of numbers
Since 72 = (2
3 )(3
2 ), it follows that 2
3 is a divisor
of 72 and 2
4 is not a divisor of 72. erefore,
2||72
3, and hence k = 3.
e correct answer is B.
166. A certain characteristic in a large population has a
distribution that is symmetric about the mean m .
If 68 percent of the distribution lies within one
standard deviation d of the mean, what percent of the
distribution is less than m + d ?
(A) 16%
(B) 32%
(C) 48%
(D) 84%
(E) 92%
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5.5 Problem Solving Answer Explanations
237
Arithmetic Statistics
Since 68% lies between m − d and m + d , a total
of (100 − 68)% = 32% lies to the left of m − d and
to the right of m + d . Because the distribution is
symmetric about m , half of the 32% lies to the
right of m + d . erefore, 16% lies to the right of
m + d , and hence (100 − 16)% = 84% lies to the
left of m + d .
e correct answer is D.
167. Four extra‐large sandwiches of exactly the same size
were ordered for m students, where m > 4. Three
of the sandwiches were evenly divided among the
students. Since 4 students did not want any of the
fourth sandwich, it was evenly divided among the
remaining students. If Carol ate one piece from each
of the four sandwiches, the amount of sandwich that
she ate would be what fraction of a whole extra‐large
sandwich?
(A) m
mm
4
4
()
+
−
(B) m
mm
24
4
()
−
−
(C) m
mm
44
4
()
−
−
(D) m
mm
48
4
()
−
−
(E) m
mm
412
4
()
−
−
Algebra Applied problems
Since each of 3 of the sandwiches was evenly
divided among m students, each piece was m
1 of a
sandwich. Since the fourth sandwich was evenly
divided among m − 4 students, each piece was
m
1
4− of the fourth sandwich. Carol ate 1 piece
from each of the four sandwiches, so she ate a
total of
mm
mm
mm
m
mm
311
4
34
4
412
4
() ()
() ()
+−=−+
−=−
−
e correct answer is E.
168. Which of the following equations has 1 + 2 as one of
its roots?
(A) x
2 + 2 x – 1 = 0
(B) x
2 – 2 x + 1 = 0
(C) x
2 + 2 x + 1 = 0
(D) x
2 – 2 x – 1 = 0
(E) x
2 – x – 1 = 0
Algebra Second-degree equations
is problem can be solved by working backwards
to construct a quadratic equation with 1+2 as
a root that does not involve radicals.
x=1+2set x to the desired value
x–1 =2subtract 1 from both sides
(x–1)
2 =2 square both sides
x
2 –2x+1 =2 expand the left side
x
2 –2x–1 =0 subtract 2 from both sides
e correct answer is D.
169. In Country C, the unemployment rate among
construction workers dropped from 16 percent on
September 1, 1992, to 9 percent on September 1,
1996. If the number of construction workers was
20 percent greater on September 1, 1996, than
on September 1, 1992, what was the approximate
percent change in the number of unemployed
construction workers over this period?
(A) 50% decrease
(B) 30% decrease
(C) 15% decrease
(D) 30% increase
(E) 55% increase
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GMAT® Offi cial Guide 2018
238
Arithmetic Percents
Let U
1 and U
2 be the numbers of unemployed
construction workers on September1, 1992,
and September 1, 1996, respectively, and let
N be the number of construction workers
on September 1, 1992. en, from the given
information, 1.2 N is the number of construction
workers on September 1, 1996, U
1 = 0.16 N , and
U
2 =0.09(1.2 N ). erefore, the percent change
from September 1, 1992, to September 1, 1996, of
unemployed construction workers is given by
UU
U
NN
N
100 %
0.09 1.2 0.16
0.16 100 %
0.108 0.16
0.16 100 %
108 160
160 100 %
13
40 100 %
13
39 100 %
1
3100 %
30%
21
1
()
−×
⎛
⎝
⎜⎞
⎠
⎟
=−×
⎛
⎝
⎜⎞
⎠
⎟
=−×
⎛
⎝⎞
⎠
=−×
⎛
⎝⎞
⎠
=− ×
⎛
⎝⎞
⎠
≈− ×
⎛
⎝⎞
⎠
≈− ×
⎛
⎝⎞
⎠
≈−
e correct answer is B.
170. In a box of 12 pens, a total of 3 are defective. If a
customer buys 2 pens selected at random from the
box, what is the probability that neither pen will be
defective?
(A)
1
6
(B)
2
9
(C) 6
11
(D) 9
16
(E)
3
4
Arithmetic Probability
Let A represent the event that the rst pen
purchased is not defective and let B represent
the event that the second pen purchased is not
defective, where A and B are dependent events.
Since there are 3 defective pens in the box of
12 pens, there are 9pens in the box that are not
defective. Using standard probability notation,
()
=PA 9
12 and P ( B , given that A has occurred)=
8
11 . (Event A has occurred so there are 11 pens
left in the box and 8 of them are not defective.)
en, using the multiplication rule for
dependent events, P (neither pen is defective)
= P ( A and B ) = P ( A ) × P ( B , given that A has
occurred)=9
12
8
11
6
11
×=.
Alternately, the probability of selecting 2pens,
neither of which is defective, from a box
containing 12 pens, 3 of which are defective, and
therefore, 9 of which are non‐defective is the
number of ways to select 2 non‐defective pens
from 9 non‐defective pens over the number of
ways to select 2 pens from 12 pens
9
2
12
2
98
2
12 11
2
6
11
=
⎛
⎝
⎜⎞
⎠
⎟
⎛
⎝
⎜⎞
⎠
⎟
=
×
×= .
e correct answer is C.
171. At a certain fruit stand, the price of each apple is
40 cents and the price of each orange is 60 cents.
Mary selects a total of 10 apples and oranges from the
fruit stand, and the average (arithmetic mean) price of
the 10 pieces of fruit is 56 cents. How many oranges
must Mary put back so that the average price of the
pieces of fruit that she keeps is 52 cents?
(A) 1
(B) 2
(C) 3
(D) 4
(E) 5
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5.5 Problem Solving Answer Explanations
239
Algebra Statistics
If Mary selected x apples, then she selected
(10 – x ) oranges. e average price of the 10 pieces
of fruit is xx40 60 10
10 56
()
+−
=. From this,
xx40 60 10
10
()
+−
=56 given
xx40 60 10
()
+−
=560 multiply both sides
by 10
xx40 600 60+− =560 distribution property
x600 20−=560 combine like terms
x20−=–40 subtract 600 from
both sides
x =2divide both sides by 20−
us, Mary selected 2 apples and 8 oranges. Next,
let y be the number of oranges Mary needs to put
back, so that the average price of the [2 + (8 – y )]
pieces of fruit Mary keeps is 52 cents. en,
y
y
40 2 60 8
28
()
()
()()()
+−
+− =52 given
+−
−
y
y
80 480 60
10 =52 distributive
property
+−y80 480 60 =y52 10
()
−
y
multiply both
sides by 10 −
−y560 60 =−y520 52 distributive
property
8 y =40 −y
subtract
520 60
from both sides
y =5divide both
sides by 8
erefore, Mary must put back 5 oranges, so that
the average price of the fruit she keeps (that is,
the average price of 2 apples and 3 oranges) is
52 cents.
e correct answer is E.
172. A pharmaceutical company received $3 million in
royalties on the rst $20million in sales of the generic
equivalent of one of its products and then $9 million
in royalties on the next $108 million in sales. By
approximately what percent did the ratio of royalties to
sales decrease from the rst $20million in sales to the
next $108 million in sales?
(A) 8%
(B) 15%
(C) 45%
(D) 52%
(E) 56%
Arithmetic Percents
e ratio of royalties to sales for the rst
$20 million in sales is 3
20, and the ratio of
royalties to sales for the next $108 million in sales
is 9
108
1
12
=. e percent decrease in the royalties
to sales ratios is 100 times the quotient of the
di erence in the ratios divided by the ratio of
royalties to sales for the rst $20 million in sales
or
1
12
3
20
3
20
100
−×=1
12
3
20
20
3100−
⎛
⎝⎞
⎠××
=1
12
20
31 100×−
⎛
⎝⎞
⎠×
=5
91 100−
⎛
⎝⎞
⎠×
=4
9100−×
≈–0.44×100
≈ 45% decrease
e correct answer is C.
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Times at Which the Door
Opened from 8:00 to 10:00
8:00 8:06 8:30 9:05
8:03 8:10 8:31 9:11
8:04 8:18 8:54 9:29
8:04 8:19 8:57 9:31
173. The light in a restroom operates with a 15-minute timer
that is reset every time the door opens as a person
goes in or out of the room. Thus, after someone
enters or exits the room, the light remains on for only
15 minutes unless the door opens again and resets the
timer for another 15 minutes. If the times listed above
are the times at which the door opened from 8:00 to
10:00, approximately how many minutes during this
two-hour period was the light off?
(A) 10
(B) 25
(C) 35
(D) 40
(E) 70
Arithmetic Operations with integers
Look for two consecutive times that are more
than 15minutes apart
8:03–8:00=3minutes
8:04–8:03=1 minute
8:04–8:04=0minutes
8:06–8:04=2minutes
8:10–8:06=4minutes
8:18–8:10=8minutes
8:19–8:18=1 minute
8:30–8:19=11minutes
8:31–8:30=1minute
8:54–8:31=23minutes, so the light is o for
23–15=8minutes
8:57–8:54=3minutes
9:05–8:57=8minutes
9:11–9:05=6minutes
9:29–9:11=18minutes, so the light is o
for18–15=3 minutes
9:31–9:29=2minutes
10:00–9:31=29minutes, so the light is o for
29–15=14minutes
us, the light is o for a total of
8+3+14=25minutes during the two-hour
period.
Alternatively, the light comes on at 8:00 when
the door is opened and is scheduled to go o at
8:15. So, when the door is opened at 8:03, twice
at 8:04, at 8:06, and 8:10, the light is still on,
but by the door being opened at these times, the
timer has been reset to turn the light o at 8:18,
8:19, 8:21, and 8:25, respectively. erefore, the
light is still on when the door is opened at 8:18,
8:19, 8:30, and 8:31, but the timer has been reset
to turn the light o at 8:33, 8:34, 8:45, and 8:46,
respectively. e light is therefore o from 8:46
until the door is opened again at 8:54, which
is an interval of 8minutes. e light is still on
when the door is opened at 8:57, 9:05, and 9:11,
but the timer has been reset to turn the light o
at 9:12, 9:20, and 9:26, respectively. e light is
o from 9:26 until the door is opened again at
9:29, which is an interval of 3minutes. e light
is still on when the door is opened again at 9:31,
and the timer has been reset to turn the light o
at 9:46. Since, according to the chart, the door is
not opened again before 10:00, the light remains
o from 9:46 until 10:00, which is an interval
of 14minutes. us, the light is o
a total of
8+3+14=25minutes during the two-hour
period.
e correct answer is B.
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5.5 Problem Solving Answer Explanations
241
60°
174. The parallelogram shown has four sides of equal
length. What is the ratio of the length of the shorter
diagonal to the length of the longer diagonal?
(A)
1
2
(B) 1
2
(C) 1
22
(D) 1
3
(E) 1
23
Geometry Quadrilaterals; Triangles
120°30°
30°
60°
First, opposite angles of a parallelogram have
equal measure, and the sum of the measures of
adjacent angles is 180°. is means that each of
the angles adjacent to the angle labeled 60° has
measure 120°.
Since all four sides of the parallelogram have
equal length, say x units, the shorter diagonal
divides the parallelogram into two isosceles
triangles. An isosceles triangle with one angle
measuring 60° is equilateral, and so the shorter
diagonal has length x units.
e longer diagonal divides the parallelogram
into two isosceles triangles with one angle
measuring 120° and each of the other angles
measuring 180 120
2
−=30°, as shown in the
gure above on the right.
30°
60°
en, because the diagonals of a parallelogram
are perpendicular and bisect each other, the two
diagonals divide the parallelogram into four
30°-60°-90° triangles, each with hypotenuse
x units long. e sides of a 30°-60°-90° triangle
are in the ratio of 1: 3:2 and so, if y represents
the length of the side opposite the 60° angle, then
xy
23
= and y =x3
2. But, y is half the length
of the longer diagonal, so the longer diagonal
has length x3 units. erefore, the ratio of the
length of the shorter diagonal to the length of the
longer diagonal is x
x3
1
3
=.
e correct answer is D.
175. If p is the product of the integers from 1 to 30,
inclusive, what is the greatest integer k for which 3
k is
a factor of p ?
(A) 10
(B) 12
(C) 14
(D) 16
(E) 18
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Arithmetic Properties of numbers
e table below shows the numbers from 1 to 30,
inclusive, that have at least one factor of 3 and
how many factors of 3 each has.
Multiples of 3
between 1 and 30 Number of factors of 3
31
623=× 1
933=× 2
1
2223=×× 1
1
535=× 1
1
8233=×× 2
21 3 7=× 1
24 2223=××× 1
27 333=×× 3
30 2 3 5=×× 1
e sum of the numbers in the right column is 14.
erefore, 3
14 is the greatest power of 3 that is a
factor of the product of the rst 30 positive integers.
e correct answer is C.
176. If n = 3
8 – 2
8 , which of the following is NOT a factor of n ?
(A) 97
(B) 65
(C) 35
(D) 13
(E) 5
Arithmetic Properties of numbers
Since 3
8 − 2
8 is the di erence of the perfect squares
(3
4 )
2 and (2
4 )
2 , then 3
8 – 2
8 = (3
4 + 2
4 )(3
4 – 2
4 ).
But 3
4 – 2
4 is also the di erence of the perfect
squares (3
2 )
2 and (2
2 )
2 so 3
4 – 2
4 = (3
2 + 2
2 )(3
2 – 2
2 )
and therefore 3
8 – 2
8 = (3
4 + 2
4 )(3
2 + 2
2 )(3
2 – 2
2 ).
It follows that 3
8 – 2
8 can be factored as
(81 + 16)(9 + 4)(9 – 4) = (97)(13)(5). erefore, 7
is not a factor of 3
8 – 2
8 , and hence 35 = 5 × 7
is not a factor of 3
8 – 2
8 . It is easy to see that each
of 97, 13, and 5 is a factor of 3
8 – 2
8 , and so is 65,
since 65 = 5 × 13, although this additional analysis
is not needed to arrive at the correct answer.
e correct answer is C.
177. In the gure shown, if the area of the shaded region is
3 times the area of the smaller circular region, then the
circumference of the larger circle is how many times
the circumference of the smaller circle?
(A) 4
(B) 3
(C) 2
(D) 3
(E) 2
Geometry Circles
Let R represent the radius of the larger circle
and r represent the radius of the smaller circle.
en the area of the shaded region is the area of
the larger circular region minus the area of the
smaller circular region, or π R
2 – π r
2 . It is given
that the area of the shaded region is three times
the area of the smaller circular region, and so
π R
2 – π r
2 = 3π r
2 . en R
2 – r
2 = 3 r
2 , and so
R
2 = 4 r
2 and R = 2 r . e circumference of the
larger circle is 2π R = 2π(2 r ) = 2(2π r ), which is
2 times the circumference of the smaller circle.
e correct answer is C.
178. Club X has more than 10 but fewer than 40 members.
Sometimes the members sit at tables with 3 members
at one table and 4 members at each of the other
tables, and sometimes they sit at tables with
3 members at one table and 5 members at each of
the other tables. If they sit at tables with 6 members at
each table except one and fewer than 6 members at
that one table, how many members will be at the table
that has fewer than 6 members?
(A) 1
(B) 2
(C) 3
(D) 4
(E) 5
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5.5 Problem Solving Answer Explanations
243
Arithmetic Properties of numbers
Let n be the number of members that Club X
has. Since the members can be equally divided
into groups of 4 each with 3 left over, and the
members can be equally divided into groups of
5 each with 3 left over, it follows that n – 3 is
divisible by both 4 and 5. erefore, n – 3 must be
a multiple of (4)(5) = 20. Also, because the only
multiple of 20 that is greater than 10 and less
than 40 is 20, it follows that n – 3 = 20, or n = 23.
Finally, when these 23 members are divided into
the greatest number of groups of 6 each, there
will be 5 members left over, since 23 = (3)(6) + 5.
e correct answer is E.
179. In order to complete a reading assignment on time,
Terry planned to read 90pages per day. However,
she read only 75 pages per day at rst, leaving
690 pages to be read during the last 6 days before the
assignment was to be completed. How many days in
all did Terry have to complete the assignment on time?
(A) 15
(B) 16
(C) 25
(D) 40
(E) 46
Algebra Applied problems
Let n be the number of days that Terry read at
the slower rate of 75 pages per day. en 75 n is
the number of pages Terry read at this slower rate,
and 75 n + 690 is the total number of pages Terry
needs to read. Also, n + 6 is the total number
of days that Terry will spend on the reading
assignment. e requirement that Terry average
90pages per day is equivalent to n
n
75 690
6
+
+=90.
en
n
n
nn
n
n
75 690
690
75 690 90 540
150 15
10
+
+=
+=+
=
=
erefore, the total number of days that Terry
has to complete the assignment on time is
n + 6 = 10 + 6 = 16.
e correct answer is B.
180. If s > 0 and r
s= s, what is r in terms of s ?
(A)
s
1
(B) s
(C) s s
(D) s3
(E)
ss
3−
Algebra Equations
Solve the equation for r as follows:
r
ss
r
ss
rs s
square both sides of the equation
multiply both sides by
2
3
=
=
=
e correct answer is D.
181. If 3 < x < 100, for how many values of x is x
3 the
square of a prime number?
(A) Two
(B) Three
(C) Four
(D) Five
(E) Nine
Arithmetic Properties of numbers
If x
3 is the square of a prime number, then
possible values of x
3 are 2
2 , 3
2 , 5
2 , 7
2 , ….
erefore, possible values of x are 3 × 2
2 = 12,
3 × 3
2 = 27, 3 × 5
2 = 75, 3 × 7
2 = 147, …. Since
only three of these values, namely 12, 27, and 75,
are between 3 and 100, there are three values of x
such that x
3 is the square of a prime number.
e correct answer is B.
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182. A researcher plans to identify each participant in a
certain medical experiment with a code consisting of
either a single letter or a pair of distinct letters written
in alphabetical order. What is the least number of
letters that can be used if there are 12 participants,
and each participant is to receive a different code?
(A) 4
(B) 5
(C) 6
(D) 7
(E) 8
Arithmetic Elementary combinatorics
None of the essential aspects of the problem
is a ected if the letters are restricted to be the
rst n letters of the alphabet, for various positive
integers n . With the 3 letters a , b , and c , there are
6 codes: a , b , c , ab , ac , and bc . With the 4 letters
a , b , c , and d , there are 10 codes: a , b , c , d , ab , ac ,
ad , bc , bd , and cd . Clearly, more than 12 codes
are possible with 5 or more letters, so the least
number of letters that can be used is 5.
e correct answer is B.
y
x
O1
1
2
183. The graph of which of the following equations is a
straight line that is parallel to line in the gure above?
(A) 3 y − 2 x = 0
(B) 3 y + 2 x = 0
(C) 3 y + 2 x = 6
(D) 2 y − 3 x = 6
(E) 2 y + 3 x = −6
Algebra Coordinate geometry
From the graph, line contains points (–3,0) and
(0,2), so the slope of line is 02
30
2
3
−
−− =. Any
line parallel to line has slope 2
3. Rewrite each
of the equations given in the answer choices in
slope‐intercept form y = mx + b , where m is the
slope and b is the y ‐intercept, to nd the equation
whose graph is a line with slope 2
3. For answer
choice A, 3 y – 2 x = 0 so 3 y = 2 x and y = x
2
3.
e graph of this equation is a line with slope 2
3.
e correct answer is A.
184. An object thrown directly upward is at a height of h feet
after t seconds, where h = –16( t – 3)
2 + 150. At what
height, in feet, is the object 2 seconds after it reaches
its maximum height?
(A) 6
(B) 86
(C) 134
(D) 150
(E) 166
Algebra Applied problems
Since ( t – 3)
2 is positive when t ≠ 3 and zero
when t = 3, it follows that the minimum value
of ( t – 3)
2 occurs when t = 3. erefore, the
maximum value of –16( t – 3)
2 , and also the
maximum value of –16( t – 3)
2 + 150, occurs
when t = 3. Hence, the height 2 seconds after the
maximum height is the value of h when t = 5, or
–16(5 – 3)
2 + 150 = 86.
e correct answer is B.
185. Which of the following is equivalent to the pair of
inequalities x +6>10 and x –3≤5?
(A) 2 ≤ x < 16
(B) 2 ≤ x < 4
(C) 2 < x ≤ 8
(D) 4 < x ≤ 8
(E) 4 ≤ x < 16
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5.5 Problem Solving Answer Explanations
245
Algebra Inequalities
Solve the inequalities separately and combine the
results.
x
x
x
x
610
4
35
8
+>
>
−≤
≤
Since x4>, then x4<. Combining x4< and
x8≤ gives x48<≤.
e correct answer is D.
186. David has d books, which is 3 times as many as Jeff
and 1
2 as many as Paula. How many books do the
three of them have altogether, in terms of d ?
(A) d
5
6
(B) d
7
3
(C) d
10
3
(D) d
7
2
(E) d
9
2
Algebra Applied problems; Simultaneous
equations
Let J be the number of books that Je has, and
let P be the number of books Paula has. en,
the given information about David’s books can
be expressed as d =3 J and d =1
2 P . Solving these
two equations for J and P gives d
3= J and 2 d = P .
us, d + J + P = d +d
3+2 d =31
3 d =10
3 d .
e correct answer is C.
187. There are 8 teams in a certain league and each team
plays each of the other teams exactly once. If each
game is played by 2 teams, what is the total number of
games played?
(A) 15
(B) 16
(C) 28
(D) 56
(E) 64
Arithmetic Operations on rational numbers
Since no team needs to play itself, each team needs
to play 7 other teams. In addition, each game needs
to be counted only once, rather than once for each
team that plays that game. Since two teams play
each game, 87
2
+=28 games are needed.
e correct answer is C.
188. At his regular hourly rate, Don had estimated the labor
cost of a repair job as $336 and he was paid that
amount. However, the job took 4 hours longer than he
had estimated and, consequently, he earned $2 per
hour less than his regular hourly rate. What was the
time Don had estimated for the job, in hours?
(A) 28
(B) 24
(C) 16
(D) 14
(E) 12
Algebra Second-degree equations
Let r be Don’s regular hourly rate and t be the
number of hours he estimated the repair job to
take. en rt = 336 is Don’s estimated labor cost.
Since Don was paid $336 for doing t + 4 hours of
work at an hourly rate of r − 2, it also follows that
( r − 2)( t + 4) = 336. en
rt
rttr
tr rt
trtt t
ttrt
tt
tt
2 4 336
2 4 8 336
2 4 8 0 since 336 from above
2 4 8 0 multiply both sides by
2 4 336 8 0 since 336
4 672 0 divide both sides by 2
24 28 0 factor
2
2
2
()()
()
()()
−+=
−+−=
−+ −= =
−+−=
−+ −= =
+− = −
−+=
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Alternatively, from the third line above,
tr
ttrt
rt
tt t
tt
tt
2480
24
336 8 0 since 336 from above
gives 336
2 4 336 8 0 multiply both sides by
4 672 0 divide both sides by 2
24 28 0 factor
2
2
()
()()
−+−=
−+
⎛
⎝⎞
⎠−= =
=
−+ −=
+− = −
−+=
So, t − 24 = 0, which means t = 24, or t + 28 = 0,
which means t = −28. Since an estimated time
cannot be negative, t = 24.
e correct answer is B.
189. If p
q1<, and p and q are positive integers, which of the
following must be greater than 1?
(A) p
q
(B) p
q2
(C) p
q2
(D) q
p2
(E)
q
p
Arithmetic Properties of numbers
Since p and q are positive integers, p
q
01<<.
A Since p
q1<, then qp>. Taking the square
root of both sides of the inequality gives
qp>. en, p
q
p
q
=, so here the
denominator will still be larger than the
numerator. CANNOT be greater than 1.
B Squaring the denominator increases the
denominator, which decreases the value of
the fraction. CANNOT be greater than 1.
C Multiplying the denominator by 2 increases
the denominator, which decreases the value
of the fraction. CANNOT be greater than 1.
D Since p
q1<, then qp>. When pq
2<,
this expression will be greater than 1, but
p2 need not be less than q . For example,
if p2= and q100=, p
q
2
100
= and
q
p
100
2
100
425 1
22
===>
.
However, if p3= and q4=, then p
q
3
4
=
and q
p
4
3
4
91
22
==<. NEED NOT be
greater than 1.
E Again, since p
q1<, then qp>. us, the
reciprocal, q
p, always has a value greater
than 1 because the numerator will always
be a larger positive integer than the
denominator. MUST be greater than 1.
e correct answer is E.
190. To mail a package, the rate is x cents for the rst
pound and y cents for each additional pound, where
xy>. Two packages weighing 3 pounds and 5 pounds,
respectively, can be mailed separately or combined as
one package. Which method is cheaper, and how much
money is saved?
(A) Combined, with a savings of xy− cents
(B) Combined, with a savings of
y
x− cents
(C) Combined, with a savings of x cents
(D) Separately, with a savings of xy− cents
(E) Separately, with a savings of y cents
Algebra Applied problems
Shipping the two packages separately would cost
xy12+ for the 3‐pound package and xy14+ for
the 5‐pound package. Shipping them together (as
a single 8‐pound package) would cost xy17+. By
calculating the sum of the costs for shipping the
two packages separately minus the cost for
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5.5 Problem Solving Answer Explanations
247
shipping the one combined package, it is possible
to determine the di erence in cost, as shown.
()
()()()
()()
+++ −+
+
−
=+−+
=+−−
=−
xy xy xy
xy xy
xyxy
xy
12 14 17 (cost for 3 lb.
cost for 5 lb.)
cost for 8 lb.
26 17 combine like
terms
2617 distribute the
negative
combine like
terms
Since xy>, this value is positive, which means it
costs more to ship two packages separately. us
it is cheaper to mail one combined package at a
cost savings of xy− cents.
e correct answer is A.
191. If money is invested at r percent interest, compounded
annually, the amount of the investment will double
in approximately r
70 years. If Pat’s parents invested
$5,000 in a long‐term bond that pays 8 percent
interest, compounded annually, what will be the
approximate total amount of the investment 18 years
later, when Pat is ready for college?
(A) $20,000
(B) $15,000
(C) $12,000
(D) $10,000
(E) $9,000
Algebra Applied problems
Since the investment will double in
r
70 70
88.75 9== ≈ years, the value of the
investment over 18 years can be approximated by
doubling its initial value twice. erefore, the
approximate value will be $5,000 2 2 $20,000
()
()()
=.
e correct answer is A.
192. On a recent trip, Cindy drove her car 290 miles,
rounded to the nearest 10miles, and used 12 gallons
of gasoline, rounded to the nearest gallon. The actual
number of miles per gallon that Cindy’s car got on this
trip must have been between
(A) 290
12.5 and 290
11.5
(B)
295
12 and 285
11.5
(C)
285
12 and 295
12
(D) 285
12.5 and 295
11.5
(E) 295
12.5 and 285
11.5
Arithmetic Estimation
e lowest number of miles per gallon can be
calculated using the lowest possible miles and
the highest amount of gasoline. Also, the highest
number of miles per gallon can be calculated
using the highest possible miles and the lowest
amount of gasoline.
Since the miles are rounded to the nearest
10miles, the number of miles is between 285
and 295. Since the gallons are rounded to the
nearest gallon, the number of gallons is between
11.5 and 12.5. erefore, the lowest number
of miles per gallon is lowest miles
highest gallons
285
12.5
=
and the highest number of miles per gallon is
highest miles
lowest gallons
295
11.5
=
e correct answer is D.
x
12 34–1–2–4–5 –3 5
0
193. Which of the following inequalities is an algebraic
expression for the shaded part of the number line
above?
(A) x3≤
(B) ≤x5
(C) x23−≤
(D) x14−≤
(E) x1
4
+≤
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248
Algebra Inequalities
e number line above shows x53−≤ ≤. To turn
this into absolute value notation, as all the choices
are written, the numbers need to be opposite
signs of the same value.
Since the distance between −5 and 3 is 8
(3–(–5)=8), that distance needs to be split in
half with −4 to one side and 4 to the other. Each
of these two values is 1 more than the values in
the inequality above, so adding 1 to all terms in
the inequality gives x414−≤ +≤, which is the
same as x14+≤.
e correct answer is E.
194. In a small snack shop, the average (arithmetic mean)
revenue was $400 per day over a 10‐day period.
During this period, if the average daily revenue was
$360 for the rst 6 days, what was the average daily
revenue for the last 4days?
(A) $420
(B) $440
(C) $450
(D) $460
(E) $480
Arithmetic; Algebra Statistics; Applied
problems
Let x be the average daily revenue
for the last 4 days. Using the formula
average sum of values
number of values ,= the information
regarding the average revenues for the 10‐day
and 6‐day periods can be expressed as follows and
solved for x :
x
x
x
x
$400 6 $360 4
10
$4, 000 $2,160 4 multiply both sides by 10
$1,840 4 subtract $2,160 from
both sides
$460 divide both sides by 4
()
=+
=+
=
=
e correct answer is D.
195. If y is the smallest positive integer such that 3,150
multiplied by y is the square of an integer, then y mustbe
(A) 2
(B) 5
(C) 6
(D) 7
(E) 14
Arithmetic Properties of numbers
To nd the smallest positive integer y such that
3,150 y is the square of an integer, rst nd the
prime factorization of 3,150 by a method similar
to the following:
3,150 10 315
2 5 3 105
253 521
2535 37
2357
22
()( )
()
()
=×
=×××
=××× ×
=×××× ×
=× × ×
To be a perfect square, 3,150y must have an
even number of each of its prime factors. At a
minimum, y must have one factor of 2 and one
factor of 7 so that 3,150 y has two factors of each
of the primes 2, 3, 5, and 7. e smallest positive
integer value of y is then (2)(7)=14.
e correct answer is E.
196. If [ x ] is the greatest integer less than or equal to x ,
what is the value of 1.6 3.4 2.7
[][][]
−+ + ?
(A) 3
(B) 4
(C) 5
(D) 6
(E) 7
Arithmetic Computation with integers
e greatest integer that is less than or equal
to −1.6 is −2. It cannot be −1 because −1 is
greater than −1.6. e greatest integer that is
less than or equal to 3.4 is 3. It cannot be 4
because 4 is greater than 3.4. e greatest integer
that is less than or equal to 2.7 is 2. It cannot
be 3 because 3 is greater than 2.7. erefore,
1.6 3.4 2.7
[][][]
−+ + =−2+3+2=3.
e correct answer is A.
![](asset-100.png)
5.5 Problem Solving Answer Explanations
249
197. In the rst week of the year, Nancy saved $1. In each
of the next 51weeks, she saved $1 more than she
had saved in the previous week. What was the total
amount that Nancy saved during the 52 weeks?
(A) $1,326
(B) $1,352
(C) $1,378
(D) $2,652
(E) $2,756
Arithmetic Operations on rational numbers
In dollars, the total amount saved is the sum
of 1, (1 + 1), (1 + 1 + 1), and so on, up to and
including the amount saved in the 52nd week,
which was $52. erefore, the total amount saved
in dollars was 1 + 2 + 3 + … + 50 + 51 + 52. is
sum can be easily evaluated by grouping the terms
as (1 + 52) + (2 + 51) + (3 + 50) + … + (26 + 27),
which results in the number 53 added to itself
26 times. erefore, the sum is (26)(53) = 1,378.
Alternatively, the formula for the sum of the
rst n positive integers is nn 1
2
()
+. erefore,
the sum of the rst 52 positive integers is
52 53
226 53 1,378
() ()
==.
e correct answer is C.
198. In a certain sequence, the term x
n is given by the
formula xx x21
2()
nn n
12
=−
−− for all n ≥ 2. If x
0 = 3
and x
1 = 2, what is the value of x
3 ?
(A) 2.5
(B) 3.125
(C) 4
(D) 5
(E) 6.75
Algebra Simplifying algebraic expressions
Given the formula xx x21
2()
nn n12
=−
−−
with
x
0 = 3 and x
1 = 2, then
x2=xx21
2
10
−
=2(2) 1
2(3)−
=5
2
x3=xx21
2
21
−
=25
2
1
2(2)
⎛
⎝
⎜⎞
⎠
⎟−
=5–1
=4
e correct answer is C.
199. During a trip, Francine traveled x percent of the total
distance at an average speed of 40 miles per hour
and the rest of the distance at an average speed of
60 miles per hour. In terms of x , what was Francine’s
average speed for the entire trip?
(A) x180
2
−
(B)
x60
4
+
(C) x300
5
−
(D) x
600
115 −
(E)
x
12,000
200+
Algebra Applied problems
Assume for simplicity that the total distance of
Francine’s trip is 100miles. en the table below
gives all of the pertinent information.
Distance Rate Time Distance
Rate
=
x 40 x
40
100 – x 60 x100
60
−
![](asset-101.png)
GMAT® Offi cial Guide 2018
250
e total time for Francine’s trip is
xx
40
100
60
+−=xx
3
120
2(100 )
120
+−
=xx3 2(100 )
120
+−
=xx3 200 2
120
+−
=x200
120
+
Francine’s average speed over the entire trip is
xx
total distance
total time
100
200
120
12,000
200
=+=+.
e correct answer is E.
200. If n = (33)
43 + (43)
33 , what is the units digit of n ?
(A) 0
(B) 2
(C) 4
(D) 6
(E) 8
Arithmetic Properties of numbers
If the units digit of an integer n is 3, then the
units digits of n
1 , n
2 , n
3 , n
4 , n
5 , n
6 , n
7 , and n
8
are, respectively, 3, 9, 7, 1, 3, 9, 7, and 1. us,
the units digit of the powers of n form the
sequence in which the digits 3, 9, 7, and 1repeat
inde nitely in that order. Since 43=(10)(4)+3, the
43rd number in the sequence is 7, and therefore
the units digit of (33)
43 is 7. Since 33=(8)(4)+1, the
33rd number of this sequence is 3, and therefore,
the units digit of (43)
33 is 3. us, the units digit
of (33)
43 +(43)
33 is the units digit of 7+3, which
is 0.
e correct answer is A.
201. TeamA and TeamB are competing against each other
in a game of tug-of-war. TeamA, consisting of 3males
and 3females, decides to line up male, female, male,
female, male, female. The lineup that TeamA chooses
will be one of how many different possible lineups?
(A) 9
(B) 12
(C) 15
(D) 36
(E) 720
Arithmetic Elementary combinatorics
Any of the 3males can be rst in the line, and
any of the 3females can be second. Either of the
2remaining males can be next, followed by either
of the 2remaining females. e last 2places in
the line are lled with the only male left followed
by the only female left. By the multiplication
principle, there are 3×3×2×2×1×1=36
di erent lineups possible.
e correct answer is D.
202. A border of uniform width is placed around a
rectangular photograph that measures 8 inches by
10 inches. If the area of the border is 144 square
inches, what is the width of the border, in inches?
(A) 3
(B) 4
(C) 6
(D) 8
(E) 9
Algebra Second-degree equations
810
8 + 2
x
10 + 2x
x
x
Note: Figure not drawn to scale.
Let x be the width, in inches, of the border. e
photograph with the border has dimensions
(10 +2 x ) inches and (8+2 x ) inches with an area
of (10 +2 x )(8+2 x )=(80+36 x +4 x
2 )square
![](asset-102.png)
5.5 Problem Solving Answer Explanations
251
inches. e photograph without the border has
dimensions 10 inches and 8 inches with an area
of (10)(8)=80square inches. e area of the
border is then the di erence between the areas
of the photograph with and without the border
or (80+36 x +4 x
2 )–80=36 x +4 x
2 square
inches. It is given that the area of the border is
144square inches so,
36 x + 4 x
2 =144
4 x
2 + 36 x − 144 =0
x
2 + 9 x − 36 =0
( x − 3)( x + 12) =0
So, x – 3 = 0, which means x = 3, or x + 12 = 0,
which means x = –12.
us, after discarding x = –12 since the width of
the border must be positive, x = 3.
e correct answer is A.
203. If d1
25
37
=× is expressed as a terminating decimal,
how many nonzero digits will d have?
(A) One
(B) Two
(C) Three
(D) Seven
(E) Ten
Arithmetic Operations on rational numbers
It will be helpful to use the fact that a factor that is
an integer power of 10 has no e ect on the number
of nonzero digits a terminating decimal has.
1
25
1
25
1
5
1
25
1
5
1
10
1
5
10 (0.2)
10 (0.0016)
0.0000016
37 33 4
34
34
34
3
×=××
=×
⎛
⎝
⎜⎞
⎠
⎟×⎛
⎝
⎜⎞
⎠
⎟
=⎛
⎝
⎜⎞
⎠
⎟×⎛
⎝
⎜⎞
⎠
⎟
=×
=×
=
−
−
e correct answer is B.
204. For any positive integer n , the sum of the rst
n positive integers equals nn 1
2
()
+. What is the sum of
all the even integers between 99 and 301?
(A) 10,100
(B) 20,200
(C) 22,650
(D) 40,200
(E) 45,150
Algebra Simplifying expressions; Arithmetic
Computation with integers
e given formula translates into
nk
nn
1 2 ... 1
2
k
n
1
∑
()
++ += = +
=
. e sum of the
even integers between 99 and 301 is the sum of
the even integers from 100 through 300, or the
sum of the 50th even integer through the 150th
even integer. To get this sum, nd the sum of the
rst 150 even integers and subtract the sum of
the rst 49 even integers. In symbols,
kk k k222 2
2150 150 1
2249 49 1
2
150 151 49 50
50 3 151 49
50 453 49
50 404
20, 200
kkkk1
150
1
49
1
150
1
49
∑∑∑∑
()
() ()
()
()
()
()
−= −
=+
⎛
⎝
⎜⎞
⎠
⎟−+
⎛
⎝
⎜⎞
⎠
⎟
=−
=−
⎡
⎣⎤
⎦
=−
=
=
====
e correct answer is B.
205. How many prime numbers between 1 and 100 are
factors of 7,150?
(A) One
(B) Two
(C) Three
(D) Four
(E) Five
![](asset-103.png)
GMAT® Offi cial Guide 2018
252
Arithmetic Properties of numbers
To nd the number of prime numbers between 1
and 100 that are factors of 7,150, nd the prime
factorization of 7,150 using a method similar to
the following:
7,150 10 715
2 5 5 143
2 5 5 11 13
()( )
()
=×
=×××
=××× ×
us, 7,150 has four prime factors: 2, 5, 11, and 13.
e correct answer is D.
206. A sequence of numbers a
1 , a
2 , a
3 , . . . is de ned as
follows: a
1 = 3, a
2 = 5, and every term in the sequence
after a
2 is the product of all terms in the sequence
preceding it, e.g., a
3 = ( a
1 )( a
2 ) and a
4 =( a
1 )( a
2 )( a
3 ). If
a
n = t and n > 2, what is the value of a
n
+ 2 in terms of t ?
(A) 4 t
(B) t
2
(C) t
3
(D) t
4
(E) t
8
Algebra Sequences
It is given that a
n =( a
1 )( a
2 )…( a
n
–1 ) and a
n = t .
erefore, a
n
+1 =( a
1 )( a
2 )…( a
n
–1 )( a
n )=
( a
n )( a
n )= t
2 and a
n
+2 =( a
1 )( a
2 )…( a
n )( a
n
+1 )=
( a
n
+1 )( a
n
+1 )=( t
2 )( t
2 )= t
4 .
e correct answer is D.
207. Last year the price per share of Stock X increased
by k percent and the earnings per share of Stock X
increased by m percent, where k is greater than m .
By what percent did the ratio of price per share to
earnings per share increase, in terms of k and m ?
(A) k
m%
(B) ( k − m )%
(C) km
k
100
100 %
()
−
+
(D) km
m
100
100 %
()
−
+
(E) km
km
100
100 %
()
−
++
Algebra Percents
If P and E are the price and earnings per share
before the increase, then kP1100
+
⎛
⎝
⎜⎞
⎠
⎟ and
mE1100
+
⎛
⎝
⎜⎞
⎠
⎟ are the price and earnings per share
after the increase. erefore, the percent increase
in the ratio of price per share to earnings per
share can be expressed as follows:
⋅
()( )
()
()
()
−×
⎛
⎝
⎜⎞
⎠
⎟
=−
⎛
⎝
⎜⎞
⎠
⎟×
⎡
⎣
⎢⎤
⎦
⎥
=
+
⎛
⎝⎞
⎠
+
⎛
⎝⎞
⎠−
⎛
⎝
⎜
⎜
⎜
⎜
⎜
⎜
⎜
⎜
⎞
⎠
⎟
⎟
⎟
⎟
⎟
⎟
⎟
⎟
×
⎡
⎣
⎢
⎢
⎢
⎢
⎢
⎢
⎢
⎢
⎢
⎤
⎦
⎥
⎥
⎥
⎥
⎥
⎥
⎥
⎥
⎥
=
+
⎛
⎝⎞
⎠
+
⎛
⎝⎞
⎠−
⎛
⎝
⎜
⎜
⎜
⎜
⎜
⎜
⎜
⎜
⎞
⎠
⎟
⎟
⎟
⎟
⎟
⎟
⎟
⎟
×
⎡
⎣
⎢
⎢
⎢
⎢
⎢
⎢
⎢
⎢
⎢
⎤
⎦
⎥
⎥
⎥
⎥
⎥
⎥
⎥
⎥
⎥
=
+
⎛
⎝⎞
⎠
+
⎛
⎝⎞
⎠−
⎛
⎝
⎜
⎜
⎜
⎜
⎜
⎜
⎜
⎜
⎞
⎠
⎟
⎟
⎟
⎟
⎟
⎟
⎟
⎟
×
⎡
⎣
⎢
⎢
⎢
⎢
⎢
⎢
⎢
⎢
⎢
⎤
⎦
⎥
⎥
⎥
⎥
⎥
⎥
⎥
⎥
⎥
=+
+−
⎛
⎝
⎜
⎜
⎜
⎞
⎠
⎟
⎟
⎟×
⎡
⎣
⎢
⎢
⎢
⎤
⎦
⎥
⎥
⎥
kP
mE
P
E
k
m
P
E
P
E
k
m
k
m
ratio after increases ratio before increases
ratio before increases 100 %
ratio after increases
ratio before increases 1 100 %
1100
1100 1 100 %
1100
1100 1 100 %
1100
1100
11 100 %
1100
1100
1 100 %
![](asset-104.png)
5.5 Problem Solving Answer Explanations
253
⋅
()( )
()
=+
+−
⎛
⎝
⎜
⎜
⎜
⎞
⎠
⎟
⎟
⎟×
⎡
⎣
⎢
⎢
⎢
⎤
⎦
⎥
⎥
⎥
=+
+−
⎛
⎝⎞
⎠×
⎡
⎣
⎢⎤
⎦
⎥
=+− +
+×
⎛
⎝
⎜⎞
⎠
⎟
=−
+×
⎛
⎝⎞
⎠
=−
+
k
m
k
m
km
m
km
m
km
m
1100
1100
100
100 1 100 %
100
100 1 100 %
100 100
100 100 %
100 100 %
100
100 %
e correct answer is D.
208. Of the 300 subjects who participated in an experiment
using virtual‐reality therapy to reduce their fear of
heights, 40 percent experienced sweaty palms,
30 percent experienced vomiting, and 75percent
experienced dizziness. If all of the subjects
experienced at least one of these effects and
35percent of the subjects experienced exactly two of
these effects, how many of the subjects experienced
only one of these effects?
(A) 105
(B) 125
(C) 130
(D) 180
(E) 195
Arithmetic Applied problems
Let a be the number who experienced only one
of the e ects, b be the number who experienced
exactly two of the e ects, and c be the number
who experienced all three of the e ects. en
a + b + c = 300, since each of the 300 participants
experienced at least one of the e ects. From the
given information, b = 105 (35% of 300), which
gives a + 105 + c = 300, or a + c = 195 (Eq. 1).
Also, if the number who experienced sweaty
palms (40% of 300, or 120) is added to the
number who experienced vomiting (30% of 300,
or 90), and this sum is added to the number who
experienced dizziness (75% of 300, or 225), then
each participant who experienced only one of the
e ects is counted exactly once, each participant
who experienced exactly two of the e ects is
counted exactly twice, and each participant who
experienced all three of the e ects is counted
exactly 3 times. erefore, a + 2 b + 3 c =
120 + 90 + 225 = 435. Using b = 105, it follows
that a + 2(105) + 3 c = 435, or a + 3 c = 225 (Eq.2).
en solving the system de ned by Eq. 1 and Eq. 2,
ac
ac
195
3 225 multiply 1st equation by 3
{
+=
+= −
ac
ac
3 3 585
3 225 add equations
−−=−
+=
⎧
⎨
⎩
⎪
−2 a =−360, or a = 180
e correct answer is D.
209. If m1
3
1=
−, then m
−2 is equal to
(A) −9
(B) −3
(C) 1
9
−
(D) 1
9
(E) 9
Arithmetic Negative exponents
Using rules of exponents, mm m
212 1
2
()
==
−−⋅ −
,
and since mm
1
3,1
3
1
9
12
2
=− = −
⎛
⎝⎞
⎠=
−− .
e correct answer is D.
210. A photography dealer ordered 60 Model X cameras
to be sold for $250 each, which represents a
20 percent markup over the dealer’s initial cost for
each camera. Of the cameras ordered, 6 were never
sold and were returned to the manufacturer for a
refund of 50 percent of the dealer’s initial cost. What
was the dealer’s approximate pro t or loss as a
percent of the dealer’s initial cost for the 60 cameras?
(A) 7% loss
(B) 13% loss
(C) 7% pro t
(D) 13% pro t
(E) 15% pro t
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GMAT® Offi cial Guide 2018
254
Arithmetic Percents
Given that $250 is 20% greater than a camera’s
initial cost, it follows that the initial cost for each
camera was $250
1.2
⎛
⎝
⎜⎞
⎠
⎟. erefore, the initial cost
for the 60cameras was 60 $ 250
1.2
⎛
⎝
⎜⎞
⎠
⎟. e total
revenue is the sum of the amount obtained from
selling 60 − 6 = 54 cameras for $250 each and
the 1
2$250
1.2
⎛
⎝
⎜⎞
⎠
⎟⎛
⎝
⎜⎞
⎠
⎟ refund for each of 6 cameras,
or 54 $250 6 1
2$250
1.2
()( )
()
+⎛
⎝
⎜⎞
⎠
⎟⎛
⎝
⎜⎞
⎠
⎟. e total
pro t, as a percent of the total initial cost, is
total revenue total initial cost
total initial cost 100 %
()( )
()
−×
⎛
⎝
⎜⎞
⎠
⎟=
total revenue
total initial cost 1 100 %
()
()
−
⎛
⎝
⎜⎞
⎠
⎟×
⎛
⎝
⎜⎞
⎠
⎟. Using
the numerical expressions obtained above,
()
()
−
total revenue
total initial cost 1
54 250 6 1
2
250
1.2
60 250
1.2
1 by substitution
54 3 1
1.2
60 1
1.2
1 by canceling 250s
54 1.2 3
60 1
by multiplying
top and bottom by 1.2
and then canceling 1.2
67.8
60 1
1.13 1
0.13
()( )
()
()
()
=
+⎛
⎝⎞
⎠⎛
⎝⎞
⎠
⎛
⎝⎞
⎠
−
=
+⎛
⎝⎞
⎠
⎛
⎝⎞
⎠
−
=+−
=−
=−
=
Finally, (0.13 × 100)% = 13%, which represents a
pro t since it is positive.
e correct answer is D.
211. Seven pieces of rope have an average (arithmetic
mean) length of 68centimeters and a median length
of 84 centimeters. If the length of the longest piece of
rope is 14 centimeters more than 4 times the length
of the shortest piece of rope, what is the maximum
possible length, in centimeters, of the longest piece of
rope?
(A) 82
(B) 118
(C) 120
(D) 134
(E) 152
Algebra Statistics
Let a , b , c , d , e , f , and g be the lengths, in
centimeters, of the pieces of rope, listed from
least to greatest. From the given information it
follows that d = 84 and g = 4 a + 14. erefore,
listed from least to greatest, the lengths are a ,
b , c , 84, e , f , and 4 a + 14. e maximum value
of 4a + 14 will occur when the maximum value
of a is used, and this will be the case only if
the shortest 3 pieces all have the same length.
erefore, listed from least to greatest, the lengths
are a , a , a , 84, e , f , and 4 a + 14. e maximum
value for 4 a + 14 will occur when e and f are
as small as possible. Since e and f are to the
right of the median, they must be at least 84
and so 84 is the least possible value for each of
e and f . erefore, listed from least to greatest,
the lengths are a , a , a , 84, 84, 84, and 4 a +14.
Since the average length is 68, it follows that
aaa a a
84 84 84 4 14
768, or 30
()
++++++ + ==
.
Hence, the maximum length of the longest piece
is (4 a + 14) = [4(30) + 14] = 134 centimeters.
e correct answer is D.
212. What is the difference between the sixth and the fth
terms of the sequence 2, 4, 7, … whose n th term is
n2n1
+−?
(A) 2
(B) 3
(C) 6
(D) 16
(E) 17
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5.5 Problem Solving Answer Explanations
255
Algebra Simplifying algebraic expressions
According to the given formula, the sixth term of
the sequence is 62 62
61 5
+=+
− and the fth
term is 5+2
5–1 =5+2
4 . en,
62 52 6 5 2 2
1 221
12
116
17
54 54
4
4
() ( )
()
()
()
+−+=−+−
=+ −
=+
=+
=
e correct answer is E.
213. From the consecutive integers –10 to 10, inclusive,
20 integers are randomly chosen with repetitions
allowed. What is the least possible value of the product
of the 20 integers?
(A) (10)
20
−
(B) (10)
10
−
(C) 0
(D) (10)19
−
(E) (10)20
−
Arithmetic Properties of numbers
If −10 is chosen an odd number of times and
10 is chosen the remaining number of times
(for example, choose −10 once and choose
10 nineteen times, or choose −10 three times and
choose 10 seventeen times), then the product
of the 20 chosen numbers will be 10 20
()
−. Note
that 10 20
()
− is less than 10 19
()
−, the only other
negative value among the answer choices.
e correct answer is E.
214. The letters D, G, I, I, and T can be used to form 5‐letter
strings such as DIGIT or DGIIT. Using these letters, how
many 5‐letter strings can be formed in which the two
occurrences of the letter I are separated by at least
one other letter?
(A) 12
(B) 18
(C) 24
(D) 36
(E) 48
Arithmetic Elementary combinatorics
ere are 6 ways to select the locations of the
2 occurrences of the letterI, and this number can
be determined by listing all such ways as shown
below, where the symbol * is used in place of the
letters D, G, and T:
I*I**, I**I*, I***I, *I*I*, *I**I, **I*I
Alternatively, the number of ways to select
the locations of the 2occurrences of the
letterI can be determined by using 5
2
⎛
⎝
⎜⎞
⎠
⎟–4=
5!
(2!)(3!)–4=10–4=6, which is the number of
ways to select 2 of the 5locations minus the 4ways
in which the 2selected locations are adjacent.
For each of these 6ways to select the locations of
the 2occurrences of the letterI, there are 6ways
to select the locations of the lettersD, G, and T,
which can be determined by using 3!=6 or by
listing all such ways:
DGT, DTG, GDT, GTD, TDG, TGD
It follows that the number of ways to select the
locations of the 5letters to form 5‐letter strings is
(6)(6)=36.
e correct answer is D.
215. Last Sunday a certain store sold copies of
NewspaperA for $1.00 each and copies of
Newspaper B for $1.25 each, and the store sold no
other newspapers that day. If r percent of the store’s
revenue from newspaper sales was from Newspaper A
and if p percent of the newspapers that the store sold
were copies of Newspaper A, which of the following
expresses r in terms of p ?
(A) p
p
100
125 −
(B) p
p
150
250 −
(C) p
p
300
375 −
(D) p
p
400
500 −
(E) p
p
500
625 −
![](asset-107.png)
GMAT® Offi cial Guide 2018
256
Algebra Simultaneous equations
Let N be the total number of newspapers
that the store sold. en, the number of
copies of Newspaper A the store sold was
p % of N =p
100
⎛
⎝
⎜⎞
⎠
⎟ N and the revenue from
those copies of Newspaper A, in dollars, was
pNpN1.00 100 100
()
⎛
⎝
⎜⎞
⎠
⎟=⎛
⎝
⎜⎞
⎠
⎟. e number of
copies of Newspaper B the store sold was
(100− p )% of N =p100
100
−
⎛
⎝
⎜⎞
⎠
⎟ N and the revenue
from those copies of Newspaper B, in dollars,
was pNpN1.25 100
100
5
4
100
100
()
−
⎛
⎝
⎜⎞
⎠
⎟=⎛
⎝⎞
⎠
−
⎛
⎝
⎜⎞
⎠
⎟.
e store’s total revenue from newspaper sales,
in dollars, was pNpN
100
5
4
100
100
⎛
⎝
⎜⎞
⎠
⎟+⎛
⎝⎞
⎠
−
⎛
⎝
⎜⎞
⎠
⎟,
and the fraction of that revenue from the sale of
Newspaper A was
pN
pNpN
p
pp
p
pp
p
p
p
p
p
p
100
100
5
4
100
100
100
4
400
500 5
400
100
4 500 5
400
100
500
400
100
400
500
4
500
+⎛
⎝⎞
⎠−
⎛
⎝
⎜⎞
⎠
⎟
=
+−
⎛
⎝
⎜⎞
⎠
⎟
=+−
=−
=⎛
⎝
⎜⎞
⎠
⎟−
⎛
⎝
⎜⎞
⎠
⎟
=−
Since r percent of the store’s newspaper sales
revenue was from Newspaper A, rp
p100
4
500 ,=−
and so rp
p
400
500 .=−
e correct answer is D.
216.
0.99999999
1.0001
0.99999991
1.0003
−=
(A) 10 8−
(B) 3(10 )
8−
(C) 3(10 )
4−
(D) 2(10 )
4−
(E) 10 4−
Arithmetic Operations on rational numbers
Calculations with lengthy decimals can be
avoided by writing 0.99999999 as 1 − 10
−8 ,
0.99999991 as 19(10)
8
−−, 1.0001 as 1 + 10 4−, and
1.0003 as 1 + 3 10 4
()
−. Doing this gives
110
110
1910
1310
110 110
110
1910
1310
110
1
19(10)
1310
110 1310 1910
1310
1 3 10 10 3 10 1 9 10
1310
210 610
1310
210 1 310
1310
210
8
4
8
4
44
4
8
4
48
4
44 8
4
44 8 8
4
48
4
44
4
4
()
() ()
()
()
() ()
()
() () ()
()
()()
()
() ()
()
()
−
+−−
+
=+
⎡
⎣⎤
⎦−
⎡
⎣⎤
⎦
+−−
+
=−−−
+
=−
⎡
⎣⎤
⎦+
⎡
⎣⎤
⎦−−
⎡
⎣⎤
⎦
+
=+−−−+
+
=+
+
=⎡
⎣⎤
⎦+
⎡
⎣⎤
⎦
+
=
−
−
−
−
−−
−
−
−
−−
−
−− −
−
−− − −
−
−−
−
−−
−
−
e correct answer is D.
217. For the past n days, the average (arithmetic mean)
daily production at a company was 50 units. If today’s
production of 90 units raises the average to 55 units
per day, what is the value of n ?
(A) 30
(B) 18
(C) 10
(D) 9
(E) 7
![](asset-108.png)
5.5 Problem Solving Answer Explanations
257
Arithmetic; Algebra Statistics; Applied
problems; Simultaneous equations
Let x be the total production of the past n days.
Using the formula average sum of values
number of values
=,
the information in the problem can be expressed
in the following two equations
x
nn
x
n
50 daily average of 50 units
over the past days
55 90
1increased daily average
when including today’s
90 units
=
=+
+
Solving the first equation for x gives xn50 .=
en substituting 50 n for x in the second
equation gives the following that can be solved
for n :
55 =n
n
50 90
1
+
+
55( n +1) =50 n +90 multiply both sides
by ( n +1)
55 n +55 =50 n +90 distribute the 55
5 n =35 subtract 50 n and 55
from both sides
n =7 divide both sides by 5
e correct answer is E.
O1
y
x
1
218. In the coordinate system above, which of the following
is the equation of line?
(A) xy236−=
(B) xy236+=
(C) xy326+=
(D) xy23 6−=−
(E) xy32 6−=−
Geometry Simple coordinate geometry
e line is shown going through the points (0,2)
and (3,0). e slope of the line can be found with
the formula slope = y
x
yy
xx
change in
change in
21
21
=−
− for
two points ( x
1 , y
1 ) and ( x
2 , y
2 ). us, the slope of
this line equals 02
30
2
3.
−
−=− Using the formula
for a line of y = mx +b , where m is the slope and
b is the y ‐intercept (in this case, 2), an equation
for this line is yx
2
32=− + . Since this equation
must be compared to the available answer choices,
the following further steps should be taken:
yx
2
32=− +
3 y = −2 x + 6 multiply both sides by 3
2 x + 3 y = 6 add 2 x to both sides
is problem can also be solved as follows. From
the graph, when x = 0, y is positive; when y = 0,
x is positive. is eliminates all but B and C. Of
these, B is the only line containing (0,2). Still
another way is to use (0,2) to eliminate A, C, and
E, and then use (3,0) to eliminate D.
e correct answer is B.
219. If a two‐digit positive integer has its digits reversed,
the resulting integer differs from the original by 27. By
how much do the two digits differ?
(A) 3
(B) 4
(C) 5
(D) 6
(E) 7
![](asset-109.png)
GMAT® Offi cial Guide 2018
258
Algebra Applied problems
Let the one two‐digit integer be represented by
10 t + s , where s and t are digits, and let the other
integer with the reversed digits be represented by
10 s + t . e information that the di erence between
the integers is 27 can be expressed in the following
equation, which can be solved for the answer.
(10 s + t ) − (10 t + s ) =27
10 s + t − 10 t − s =27 distribute the negative
9 s − 9 t =27 combine like terms
s − t =3 divide both sides by 9
us, it is seen that the two digits s and t di er by3.
e correct answer is A.
220. In an electric circuit, two resistors with resistances x
and y are connected in parallel. In this case, if r is the
combined resistance of these two resistors, then the
reciprocal of r is equal to the sum of the reciprocals of
x and y . What is r in terms of x and y ?
(A) xy
(B) xy+
(C)
xy
1
+
(D) xy
xy+
(E)
xy
xy
+
Algebra Applied problems
Note that two numbers are reciprocals of each
other if and only if their product is 1. us
the reciprocals of r , x , and y are r
1, x
1, and
y
1, respectively. So, according to the problem,
rxy
111
.=+ To solve this equation for r , begin
by creating a common denominator on the right
side by multiplying the first fraction by y
y and the
second fraction by x
x:
rxy
r
y
xy
x
xy
r
xy
xy
rxy
xy
111
1
1combine the fractions on the right side
invert the fractions on both sides
=+
=+
=+
=+
e correct answer is D.
221. Xavier, Yvonne, and Zelda each try independently to
solve a problem. If their individual probabilities for
success are 1
4, 1
2, and 5
8, respectively, what is the
probability that Xavier and Yvonne, but not Zelda, will
solve the problem?
(A)
11
8
(B)
7
8
(C) 9
64
(D) 5
64
(E) 3
64
Arithmetic Probability
Since the individuals’ probabilities are
independent, they can be multiplied to figure
out the combined probability. e probability of
Xavier’s success is given as 1
4, and the probability of
Yvonne’s success is given as 1
2. Since the probability
of Zelda’s success is given as 5
8, then the probability
of her NOT solving the problem is 15
8
3
8.−=
us, the combined probability is
1
4
1
2
3
8
3
64 .
⎛
⎝⎞
⎠⎛
⎝
⎜⎞
⎠
⎟⎛
⎝
⎜⎞
⎠
⎟=
e correct answer is E.
![](asset-10a.png)
5.5 Problem Solving Answer Explanations
259
222. If xx x
11
1
1
4
−+=+, then x could be
(A) 0
(B) –1
(C) –2
(D) –3
(E) –4
Algebra Second-degree equations
Solve the equation for x . Begin by multiplying
all the terms by xx x14
()()
++ to eliminate the
denominators.
xx
11
1
−+ = x
1
4+
xx xx14 4
()()()
++−+
= xx 1
()
+
( x +4)( x +1– x ) =xx 1
()
+factor the ( x +4) out
front on the left side
x41
()()
+=xx 1
()
+simplify
( x +4) =xx
2+distribute the x on
the right side
4= x
2 subtract x from both
sides
±2= x take the square root
of both sides
Both − 2 and 2 are square roots of 4 since
24
2
()
−=
and 24
2
()
=. us, x could be − 2.
is problem can also be solved as follows.
Rewrite the left side as, xx
xx xx
1
1
1
1,
()
() ()
+−
+=+
then set equal to the right side to get
xx x
1
1
1
4.
()
+=+ Next, cross multiply:
(1)( x +4)= x ( x +1)(1). erefore, xxx42
+= +,
or x4
2=, so x2=± .
e correct answer is C.
223. 1
2
1
4
1
16
32 1
⎛
⎝
⎜⎞
⎠
⎟⎛
⎝
⎜⎞
⎠
⎟⎛
⎝
⎜⎞
⎠
⎟=
−− −
(A) 1
2
48
⎛
⎝
⎜⎞
⎠
⎟
−
(B) 1
2
11
⎛
⎝
⎜⎞
⎠
⎟
−
(C) 1
2
6
⎛
⎝
⎜⎞
⎠
⎟
−
(D) 1
8
11
⎛
⎝
⎜⎞
⎠
⎟
−
(E) 1
8
6
⎛
⎝
⎜⎞
⎠
⎟
−
Arithmetic Operations on rational numbers
It is clear from the answer choices that all three
factors need to be written with a common
denominator, and they thus become
⎛
⎝⎞
⎠=⎛
⎝⎞
⎠
⎛
⎝⎞
⎠=⎛
⎝⎞
⎠
⎛
⎝
⎜⎞
⎠
⎟=⎛
⎝⎞
⎠
⎛
⎝⎞
⎠=⎛
⎝⎞
⎠
⎛
⎝
⎜⎞
⎠
⎟=⎛
⎝⎞
⎠
⎛
⎝⎞
⎠⎛
⎝⎞
⎠⎛
⎝⎞
⎠=
⎛
⎝⎞
⎠⎛
⎝⎞
⎠⎛
⎝⎞
⎠=⎛
⎝⎞
⎠=⎛
⎝⎞
⎠
−−
−−−
−−−
−−−
−−− −−− −
1
2
1
2
1
4
1
2
1
2
1
16
1
2
1
2
So, 1
2
1
4
1
16
1
2
1
2
1
2
1
2
1
2.
33
2224
14
14
321
344 344 11
e correct answer is B.
![](asset-10b.png)
GMAT® Offi cial Guide 2018
260
a°
224. The gure shown above consists of a shaded 9-sided
polygon and 9unshaded isosceles triangles. For each
isosceles triangle, the longest side is a side of the
shaded polygon and the two sides of equal length are
extensions of the two adjacent sides of the shaded
polygon. What is the value of a?
(A) 100
(B) 105
(C) 110
(D) 115
(E) 120
Geometry Polygons
a°
x°
x°x°
x
°
x°
x°
x°
x°
x°
x°
x°
x°x°
Let x° represent the measure of each base angle
of the triangle with vertex angle labeled a°. Each
base angle of this triangle and one base angle of a
triangle with which it shares a vertex are vertical
angles and have the same measure. us, the base
angles of these triangles also have measure x°.
is pattern continues for the base angles of each
pair of triangles that share a vertex, so each base
angle of each of the 9triangles has measure x°, as
shown above. Also, the vertex angle of each of the
9triangles has measure a°=180°–2x°.
Each interior angle of the shaded polygon has
measure (180–x)° since each forms a straight
angle with an angle that has measure x°, and
the sum of the measures is (9)(180–x)°. But
the sum of the interior angles of a polygon with
nsides is (n–2)(180°), so the sum of the interior
angles of a 9-sided polygon is (7)(180°)=1,260°.
erefore, (9)(180–x)°=1,260° and x=40.
Finally, a=180–2x=180–2(40)=100.
e correct answer is A.
225. List T consists of 30 positive decimals, none of which
is an integer, and the sum of the 30 decimals is S . The
estimated sum of the 30 decimals, E , is de ned as
follows. Each decimal in T whose tenths digit is even
is rounded up to the nearest integer, and each decimal
in T whose tenths digit is odd is rounded down to the
nearest integer; E is the sum of the resulting integers.
If 1
3 of the decimals in T have a tenths digit that is even,
which of the following is a possible value of E – S ?
I. 16
II. 6
III. 10
−
(A) I only
(B) I and II only
(C) I and III only
(D) II and III only
(E) I, II, and III
Arithmetic Operations on rational numbers
Since 1
3 of the 30 decimals in T have an even
tenths digit, it follows that 1
330 10
()
= decimals
in T have an even tenths digit. Let T
E represent
the list of these 10decimals, let S
E represent the
sum of all 10 decimals in T
E , and let E
E represent
the estimated sum of all 10 decimals in T
E after
rounding. e remaining 20 decimals in T have
an odd tenths digit. Let T
O represent the list of
these 20 remaining decimals, let S
O represent
the sum of all 20 decimals in T
O , and let E
O
represent the estimated sum of all 20 decimals in
T
O after rounding. Note that E = E
E + E
O
and S = S
E + S
O and hence E − S =
( E
E + E
O ) − ( S
E + S
O ) = ( E
E − S
E ) + ( E
O − S
O ).
e least values of E
E − S
E occur at the extreme
where each decimal in T
E has tenths digit 8.
Here, the di erence between the rounded integer
and the original decimal is greater than 0.1. (For
![](asset-10c.png)
5.5 Problem Solving Answer Explanations
261
example, the di erence between the integer 15
and 14.899 that has been rounded to 15 is 0.101.)
Hence, E
E − S
E > 10(0.1) = 1. e greatest values
of E
E − S
E occur at the other extreme, where
each decimal in T
E has tenths digit 0. Here, the
di erence between the rounded integer and the
original decimal is less than 1. (For example, the
di erence between the integer 15 and 14.001 that
has been rounded to 15 is 0.999.)
Hence, E
E − S
E < 10(1) = 10. us, 1 < E
E − S
E < 10.
Similarly, the least values of E
O − S
O occur at the
extreme where each decimal in T
O has tenths
digit 9. Here, the di erence between the rounded
integer and the original decimal is greater than −1.
(For example, the di erence between the integer
14 and 14.999 that has been rounded to 14 is
−0.999.) Hence E
O − S
O > 20(−1) = −20.
e greatest values of E
O − S
O occur at the other
extreme where each decimal in T
O has tenths
digit 1. Here, the di erence between the rounded
integer and the original decimal is less than
or equal to −0.1. (For example, the di erence
between the integer 14 and 14.1 that has been
rounded to 14 is −0.1.)
Hence, E
O − S
O ≤ 20(−0.1) = −2.
us, −20 < E
O − S
O ≤ −2.
Adding the inequalities 1 < E
E − S
E < 10 and −20 <
E
O − S
O ≤ −2 gives −19 < ( E
E – S
E ) + ( E
O − S
O ) < 8.
erefore, −19 < ( E
E + E
O ) − ( S
E + S
O ) < 8 and
−19 < E − S < 8. us, of the values −16, 6,
and 10 for E − S , only −16 and 6 are possible.
Note that if T contains 10 repetitions of the
decimal 1.8 and 20 repetitions of the decimal 1.9,
S = 10(1.8) + 20(1.9) = 18 + 38 = 56,
E = 10(2) + 20(1) = 40, and E − S = 40 − 56 = −16.
Also, if T contains 10 repetitions of the decimal
1.2 and 20 repetitions of the decimal 1.1,
S = 10(1.2) + 20(1.1) = 12 + 22 = 34,
E = 10(2) + 20(1) = 40, and E − S = 40 − 34 = 6.
e correct answer is B.
226. If xx56
−=, then x has how many possible values?
(A) None
(B) One
(C) Two
(D) A nite number greater than two
(E) An in nite number
Algebra Second-degree equations
Solve the equation to determine how many values
are possible for x .
xx
xx
xx
xx
x
56
56
056
032
3or2
2
2
()()
−=
−=
=−+
=− −
=
e correct answer is C.
227. Seed mixture X is 40 percent ryegrass and 60 percent
bluegrass by weight; seed mixture Y is 25 percent
ryegrass and 75 percent fescue. If a mixture of X and
Y contains 30 percent ryegrass, what percent of the
weight of the mixture is X?
(A) 10%
(B)
33 1
3%
(C) 40%
(D) 50%
(E)
66 2
3%
Algebra Applied problems
Let X be the amount of seed mixture X in
the final mixture, and let Y be the amount of
seed mixture Y in the final mixture. e final
mixture of X and Y needs to contain 30 percent
ryegrass seed, so any other kinds of grass seed
are irrelevant to the solution to this problem. e
information about the ryegrass percentages for X,
Y, and the final mixture can be expressed in the
following equation and solved for X .
XY XY
XY XY
XY X
Y
XY
0.40 0.25 0.30
0.40 0.25 0.30 0.30 distribute the
0.30 on the
right side
0.10 0.05 subtract 0.30
and 0.25 from
both sides
0.5 divide both
sides by 0.10
()
+= +
+= +
=
=
![](asset-10d.png)
GMAT® Offi cial Guide 2018
262
Using this, the percent of the weight of the
combined mixture XY
()
+ that is X is
X
XY
Y
YY
Y
Y
0.5
0.5
0.5
1.5
0.5
1.5 0.333 33 1
3%
+=+=== =
e correct answer is B.
228. How many of the integers that satisfy the inequality
xx
x
(2)(3)
20
++
−> are less than 5?
(A) 1
(B) 2
(C) 3
(D) 4
(E) 5
Algebra Inequalities
–3 –2 2
x + 3
–––0+++++++++++++++
–––––0+++++++++++++
––––––––––––––0++++
x + 2
x – 2
x
Pictorially, the number line above shows the
algebraic signs of the expressions ( x + 3), ( x + 2),
and ( x − 2). For example, x + 3 is 0 when x = −3,
x + 3 is negative when x < −3, and x + 3 is positive
when x > −3. e expression xx
x
(2)(3)
2
++
−
will be positive in the intervals of the number
line where the number of minus signs is even.
erefore xx
x
(2)(3)
2
++
− is positive for values of
x such that −3 < x < −2 and for values of x such
that x > 2. e only integer values of x in these
intervals that are also less than 5 are 3 and 4.
Also, xx
x
(2)(3)
2
++
− will be zero if and only if
( x + 2)( x + 3) = 0, which has two integer solutions
less than 5, namely, x = −2 and x = −3.
erefore, there are four integers less than 5 that
satisfy xx
x
(2)(3)
20
++
−≥ and those integers are
−3, −2, 3, and 4.
Alternatively, xx
x
(2)(3)
2
++
− will be zero if and
only if ( x + 2)( x + 3) = 0, which has two integer
solutions less than 5, namely, x = −2 and x = −3.
Also, xx
x
(2)(3)
2
++
− will be positive if
( x + 2)( x + 3) and x − 2 are both positive or both
negative, and for no other values of x . On the one
hand, ( x + 2)( x + 3) will be positive when x + 2
and x + 3 are both positive, which will be the case
when x > −2 and x > −3 and thus when x > −2.
On the other hand, ( x + 2)( x + 3) will be positive
when x + 2 and x + 3 are both negative, which
will be the case when x < −2 and x < −3 and thus
when x < −3. So, ( x + 2)( x + 3) will be positive
when x < −3 or x > −2. ( is result can also be
deduced from the fact that the graph of y =
( x + 2)( x + 3) is a parabola with x ‐intercepts
(−2,0) and (−3,0) that opens upward.) Since
x − 2 will be positive when x > 2, it follows that
( x + 2)( x + 3) and x − 2 are both positive when
x >2, which includes exactly two integer values
less than 5, namely, x = 3 and x = 4. ere are
no integer values of x such that ( x + 2)( x + 3)
and x − 2 are both negative, since ( x + 2)( x + 3)
is negative if and only if x lies between −3 and
−2 and there are no integers between −3 and −2.
erefore, there are exactly 4 integer values of x
less than 5 such that xx
x
(2)(3)
20
++
−≥.
Two of the values, x = −2 and x = −3, arise from
solutions to xx
x
(2)(3)
20
++
−=, and two of the
values, x = 3 and x = 4, arise from solutions to
xx
x
(2)(3)
20
++
−>.
e correct answer is D.
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5.5 Problem Solving Answer Explanations
263
229. Of the 150 houses in a certain development,
60percent have air-conditioning, 50percent have a
sunporch, and 30percent have a swimming pool. If
5of the houses have all three of these amenities and
5have none of them, how many of the houses have
exactly two of these amenities?
(A) 10
(B) 45
(C) 50
(D) 55
(E) 65
Arithmetic Sets
air-conditioning
sunporch swimming
pool
c
bd
55
ea f
Since 60% of the 150houses have air-conditioning,
b+c+d+5=0.6(150)=90, so b+c+d=85
(i). Similarly, since 50% have a sunporch,
a+b+f+5=0.5(150)=75, so a+b+f=70
(ii). Likewise, since 30% have a swimming pool,
d+e+f+5=0.3(150)=45, so d+e+f=40
(iii). Adding equations (i), (ii), and (iii) gives
(b+c+d)+(a+b+f)+(d+e+f)=195,
or a+2b+c+2d+e+2f=195 (iv). But
a+b+c+d+e+f+5+5=150, or
a+b+c+d+e+f= 140 (v). Subtracting
equation (v) from equation (iv) gives
b+d+f=55, so 55 houses have exactly two of
the amenities.
e correct answer is D.
230. The value of 2222
5
14 15 16 17
+++
−−−−
is how many
times the value of 2
(−17) ?
(A)
3
2
(B)
5
2
(C) 3
(D) 4
(E) 5
Arithmetic Negative exponents
If the value of 2222
5
14 15 16 17
+++
−−−−
is x times
the value of 2 17−, then
x
x
22222
5
2222
5
2
2222
52
2222 2
5
2222
5
2222
5
8421
5
3
17 14 15 16 17
14 15 16 17
17
14 15 16 17 17
14 15 16 17 17
14 17 15 17 16 17 17 17
3210
()
()
=+++
=
+++
=+++×
=+++ ×
=+++
=+++
=+++
=
−−−−−
−−−−
−
−−−−
−−−−
−+ −+ −+ −+
e correct answer is C.
264
6.0 Data Suffi ciency
265
6.0 Data Suffi ciency
6.0 Data Suffi ciency
Data sufficiency questions appear in the Quantitative section of the GMAT ® exam. Multiple‐choice
data sufficiency questions are intermingled with problem solving questions throughout the section. You
will have 75 minutes to complete the Quantitative section of the GMAT exam, or about 2 minutes to
answer each question. ese questions require knowledge of the following topics:
• Arithmetic
• Elementary algebra
• Commonly known concepts of geometry
Data sufficiency questions are designed to measure your ability to analyze a quantitative problem,
recognize which given information is relevant, and determine at what point there is sufficient
information to solve a problem. In these questions, you are to classify each problem according to the
five fixed answer choices, rather than find a solution to the problem.
Each data sufficiency question consists of a question, often accompanied by some initial information,
and two statements, labeled (1) and (2), which contain additional information. You must decide whether
the information in each statement is sufficient to answer the question or—if neither statement provides
enough information—whether the information in the two statements together is sufficient. It is also
possible that the statements, in combination, do not give enough information to answer the question.
Begin by reading the initial information and the question carefully. Next, consider the first statement.
Does the information provided by the first statement enable you to answer the question? Go on to the
second statement. Try to ignore the information given in the first statement when you consider whether
the second statement provides information that, by itself, allows you to answer the question. Now you
should be able to say, for each statement, whether it is sufficient to determine the answer.
Next, consider the two statements in tandem. Do they, together, enable you to answer the question?
Look again at your answer choices. Select the one that most accurately reflects whether the statements
provide the information required to answer the question.
GMAT® Offi cial Guide 2018
266
6.1 Test-Taking Strategies
1. Do not waste valuable time solving a problem.
You only need to determine whether sufficient information is given to solve it.
2. Consider each statement separately.
First, decide whether each statement alone gives sufficient information to solve the problem. Be sure to
disregard the information given in statement (1) when you evaluate the information given in statement
(2). If either, or both, of the statements give(s) sufficient information to solve the problem, select the
answer corresponding to the description of which statement(s) give(s) sufficient information to solve
the problem.
3. Judge the statements in tandem if neither statement is sufficient by itself.
It is possible that the two statements together do not provide sufficient information. Once you decide,
select the answer corresponding to the description of whether the statements together give sufficient
information to solve the problem.
4. Answer the question asked.
For example, if the question asks, “What is the value of y ?” for an answer statement to be sufficient,
you must be able to find one and only one value for y . Being able to determine minimum or maximum
values for an answer (e.g., y = x +2) is not sufficient, because such answers constitute a range of values
rather than the specific value of y .
5. Be very careful not to make unwarranted assumptions based on the images
represented.
Figures are not necessarily drawn to scale; they are generalized figures showing little more than
intersecting line segments and the relationships of points, angles, and regions. For example, if a figure
described as a rectangle looks like a square, do not conclude that it is actually a square just by looking at
the figure.
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267
6.1 Data Suffi ciency Test-Taking Strategies
If statement 1 is sufficient , then the answer must be A or D.
If statement 2 is not sufficient , then the answer must be A.
If statement 2 is sufficient , then the answer must be D.
If statement 1 is not sufficient , then the answer must be B, C, or E.
If statement 2 is sufficient , then the answer must be B.
If statement 2 is not sufficient , then the answer must be C or E.
If both statements together are sufficient , then the answer must be C.
If both statements together are still not sufficient , then the answer must be E.
Yes
Yes
Yes
Yes No
No
No
No
Is Statement 1 Sucient Alone?
Is Statement 2 Sucient Alone?
Is Statement 2 Sucient Alone?
Are Statements 1 & 2
Sucient Together?
Correct
Answer
Is D
Correct
Answer
Is A
Correct
Answer
Is B
Correct
Answer
Is C
Correct
Answer
Is E
GMAT® Offi cial Guide 2018
268
6.2 The Directions
ese directions are similar to those you will see for data sufficiency questions when you take the
GMAT exam. If you read the directions carefully and understand them clearly before going to sit for
the test, you will not need to spend much time reviewing them when you take the GMAT exam.
Each data sufficiency problem consists of a question and two statements, labeled (1) and (2), that
give data. You have to decide whether the data given in the statements are sufficient for answering the
question. Using the data given in the statements plus your knowledge of mathematics and everyday
facts (such as the number of days in July or the meaning of counterclockwise ), you must indicate whether
the data given in the statements are sufficient for answering the questions and then indicate one of the
following answer choices:
(A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer the
question asked;
(B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer the
question asked;
(C) BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,
but NEITHER statement ALONE is sufficient;
(D) EACH statement ALONE is sufficient to answer the question asked;
(E) Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,
and additional data are needed.
NOTE: In data sufficiency problems that ask for the value of a quantity, the data given in the
statements are sufficient only when it is possible to determine exactly one numerical value for
the quantity.
Numbers: All numbers used are real numbers.
Figures: A figure accompanying a data sufficiency problem will conform to the information given
in the question but will not necessarily conform to the additional information given in statements
(1) and (2).
Lines shown as straight can be assumed to be straight and lines that appear jagged can also be assumed
to be straight.
You may assume that the positions of points, angles, regions, and so forth exist in the order shown and
that angle measures are greater than zero degrees.
All figures lie in a plane unless otherwise indicated.
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270
6.3 Practice Questions
Each data suffi ciency problem consists of a question and two statements, labeled (1) and (2), which
contain certain data. Using these data and your knowledge of mathematics and everyday facts
(such as the number of days in July or the meaning of the word counterclockwise ), decide whether
the data given are suffi cient for answering the question and then indicate one of the following
answer choices:
A Statement (1) ALONE is suffi cient, but statement (2) alone is not suffi cient.
B Statement (2) ALONE is suffi cient, but statement (1) alone is not suffi cient.
C BOTH statements TOGETHER are suffi cient, but NEITHER statement ALONE is suffi cient.
D EACH statement ALONE is suffi cient.
E Statements (1) and (2) TOGETHER are NOT suffi cient.
Note: In data suffi ciency problems that ask for the value of a quantity, the data given in the statements
are suffi cient only when it is possible to determine exactly one numerical value for the quantity.
Example:
xº
yºzº
P
QR
In, Δ PQR what is the value of x ?
(1) PQ = PR
(2) y = 40
Explanation: According to statement (1) PQ = PR ; therefore, ΔPQR is isosceles and y = z . Since
x + y + z = 180, it follows that x + 2 y = 180. Since statement (1) does not give a value for y , you cannot
answer the question using statement (1) alone. According to statement (2), y = 40; therefore,
x + z = 140. Since statement (2) does not give a value for z , you cannot answer the question using
statement (2) alone. Using both statements together, since x + 2 y = 180 and the value of y is given,
you can fi nd the value of x . Therefore, BOTH statements (1) and (2) TOGETHER are suffi cient to
answer the questions, but NEITHER statement ALONE is suffi cient.
Numbers: All numbers used are real numbers.
Figures:
• Figures conform to the information given in the question, but will not necessarily conform to the
additional information given in statements (1) and (2).
• Lines shown as straight are straight, and lines that appear jagged are also straight.
• The positions of points, angles, regions, etc., exist in the order shown, and angle measures are greater
than zero.
• All fi gures lie in a plane unless otherwise indicated.
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6.3 Data Suffi ciency Practice Questions
271
B
C
D
20°
A
231. In the gure above, point D is on
A
C. What is the
degree measure of ∠ BAC ?
(1) The measure of ∠ BDC is 60°.
(2) The degree measure of ∠ BAC is less than the
degree measure of ∠ BCD .
232. A citrus fruit grower receives $15 for each crate of
oranges shipped and $18 for each crate of grapefruit
shipped. How many crates of oranges did the grower
ship last week?
(1) Last week the number of crates of oranges that
the grower shipped was 20 more than twice the
number of crates of grapefruit shipped.
(2) Last week the grower received a total of
$38,700 from the crates of oranges and
grapefruit shipped.
233. A certain mixture of paint requires blue, yellow, and
red paints in ratios of 2:3:1, respectively, and no other
ingredients. If there are ample quantities of the blue
and red paints available, is there enough of the yellow
paint available to make the desired amount of the
mixture?
(1) Exactly 20quarts of the mixture are needed.
(2) Exactly 10quarts of the yellow paint are available.
234. If Pat saved $600 of his earnings last month, how
much did Pat earn last month?
(1) Pat spent 1
2 of his earnings last month for living
expenses and saved 1
3 of the remainder.
(2) Of his earnings last month, Pat paid twice as
much in taxes as he saved.
O
y
x
R
P
Q
235. In the xy ‐plane above, is angle QPR a right angle?
(1) Points P and Q have the same x ‐coordinate.
(2) Points P and R have the same y ‐coordinate.
236. Each of the marbles in a jar is either red or white
orblue. If one marble is to be selected at random
from the jar, what is the probability that the marble
will be blue?
(1) There are a total of 24 marbles in the jar, 8 of
which are red.
(2) The probability that the marble selected will be
white is 1
2.
z
w
y
x
237. In the gure above, what is the value of z ?
(1) x = y = 1
(2) w = 2
238. Water is pumped into a partially lled tank at a
constant rate through an inlet pipe. At the same time,
water is pumped out of the tank at a constant rate
through an outlet pipe. At what rate, in gallons per
minute, is the amount of water in the tank increasing?
(1) The amount of water initially in the tank is
200gallons.
(2) Water is pumped into the tank at a rate of
10gallons per minute and out of the tank at a
rate of 10gallons every 21
2 minutes.
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GMAT® Offi cial Guide 2018
272
239. What is the value of 10 percent of y ?
(1) 5 percent of y is 60.
(2) y is 80 percent of 1,500.
240. What is the cube root of w ?
(1) The 5th root of w is 64.
(2) The 15th root of w is 4.
241. If sequence S has 120 terms, what is the 105thterm
of S ?
(1) The rst term of S is –8.
(2) Each term of S after the rst term is 10more
than the preceding term.
242. The number of seats in the rst row of an auditorium
is 18 and the number of seats in each row thereafter
is 2more than in the previous row. What is the total
number of seats in the rows of the auditorium?
(1) The number of rows of seats in the auditorium
is27.
(2) The number of seats in the last row is 70.
243. If u > 0 and v > 0, which is greater, u
v or v
u ?
(1) u = 1
(2) v > 2
244. What was the range of the selling prices of the
30wallets sold by a certain store yesterday?
(1)
1
3 of the wallets had a selling price of $24 each.
(2) The lowest selling price of the wallets was 1
3 the
highest selling price of the wallets.
245. Three houses are being sold through a real estate
agent. What is the asking price for the house with the
second‐largest asking price?
(1) The difference between the greatest and the
least asking price is $130,000.
(2) The difference between the two greater asking
prices is $85,000.
246. Is rw = 0 ?
(1) −6 < r < 5
(2) 6 < w < 10
247. Is =
x
y
1 ?
(1) xy = 1
(2) =
xy
11
248. How many people in a group of 50 own neither a fax
machine nor a laser printer?
(1) The total number of people in the group who own
a fax machine or a laser printer or both is less
than50.
(2) The total number of people in the group who own
both a fax machine and a laser printer is 15.
249. What is the value of w
–2 ?
(1) w
–1 = 1
2
(2) w
3 = 8
250. A certain investment earned a xed rate of 4 percent
interest per year, compounded annually, for ve years.
The interest earned for the third year of the investment
was how many dollars greater than that for the rst
year?
(1) The amount of the investment at the beginning of
the second year was $4,160.00.
(2) The amount of the investment at the beginning of
the third year was $4,326.40.
251. On a recent trip, Mary drove 50 miles. What was the
average speed at which she drove the 50 miles?
(1) She drove 30 miles at an average speed of
60miles per hour and then drove the remaining
20miles at an average speed of 50 miles
per hour.
(2) She drove a total of 54 minutes.
252. What is the value of t ?
(1) s + t = 6 + s
(2) t
3 = 216
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6.3 Data Suffi ciency Practice Questions
273
253. For a certain car repair, the total charge consisted of
a charge for parts, a charge for labor, and a 6 percent
sales tax on both the charge for parts and the charge
for labor. If the charge for parts, excluding sales tax,
was $50.00, what was the total charge for the repair?
(1) The sales tax on the charge for labor was$9.60.
(2) The total sales tax was $12.60.
254. George has a total of B books in his library, 25 of
which are hardcover ction books. What is the
value of B ?
(1) 40 of the B books are ction and the rest are
non ction.
(2) 60 of the B books are hardcovers and the rest
are paperbacks.
255. Is w + h
4 positive?
(1) h is positive.
(2) w is positive.
256. In Mr. Smith’s class, what is the ratio of the number of
boys to the number of girls?
(1) There are 3 times as many girls as boys in
Mr.Smith’s class.
(2) The number of boys is 1
4 of the total number of
boys and girls in Mr. Smith’s class.
257. If the sequence S has 300 terms, what is the 293rd
term of S ?
(1) The 298th term of S is –616, and each
term of S after the rst is 2 less than the
precedingterm.
(2) The rst term of S is –22.
258. If a is a 3-digit integer and bis a 3-digit integer, is the
units digit of the product of aandb greater than 5 ?
(1) The units digit of a is 4.
(2) The units digit of b is 7.
259. In each of the last ve years, Company K donated
p percent of its annual pro ts to a certain scholarship
fund. Did Company K donate more than $10,000 to
the scholarship fund last year?
(1) Two years ago, Company K had annual pro ts
of $3 million and donated $15,000 to the
scholarship fund.
(2) Last year, Company K had annual pro ts of
$2.5million.
z
y
x
260. Is the area of the triangular region above less than 20 ?
(1) x2 + y2 ≠ z2
(2) x + y < 13
261. A , B , C , and D are points on a line. If C is the midpoint
of line segment AB and if D is the midpoint of line
segment CB , is the length of line segment DB greater
than5?
(1) The length of line segment AC is greater than8.
(2) The length of line segment CD is greater than6.
262. The people in a line waiting to buy tickets to a show
are standing one behind the other. Adam and Beth
are among the people in the line, and Beth is standing
behind Adam with a number of people between them. If
the number of people in front of Adam plus the number
of people behind Beth is 18, how many people in the
line are behind Beth?
(1) There are a total of 32 people in the line.
(2) 23 people in the line are behind Adam.
263. Square ABCD is inscribed in circle O . What is the area
of square region ABCD ?
(1) The area of circular region O is 64π.
(2) The circumference of circle O is 16π.
264. Lines k and m are parallel to each other. Is the slope of
line k positive?
(1) Line k passes through the point (3,2).
(2) Line m passes through the point (–3,2).
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GMAT® Offi cial Guide 2018
274
265. In cross section, a tunnel that carries one lane of
one‐way traf c is a semicircle with radius 4.2m. Is the
tunnel large enough to accommodate the truck that is
approaching the entrance to the tunnel?
(1) The maximum width of the truck is 2.4m.
(2) The maximum height of the truck is 4m.
266. In a certain group of 50 people, how many are doctors
who have a law degree?
(1) In the group, 36 people are doctors.
(2) In the group, 18 people have a law degree.
267. Of a group of 50 households, how many have at least
one cat or at least one dog, but not both?
(1) The number of households that have at least one
cat and at least one dog is 4.
(2) The number of households that have no cats and
no dogs is 14.
268. On a certain date, Hannah invested $5,000 at
x percent simple annual interest and a different amount
at y percent simple annual interest. Whatamount did
Hannah invest at y percent simpleannualinterest?
(1) The total amount of interest earned by Hannah’s
two investments in one year was $900.
(2) Hannah invested the $5,000 at 6 percent simple
annual interest.
269. Do at least 60 percent of the students in Pat’s class
walk to school?
(1) At least 60 percent of the female students
inPat’s class walk to school.
(2) The number of students in Pat’s class who walk
to school is twice the number of students who
do not walk to school.
270. The pro t from the sale of a certain appliance
increases, though not proportionally, with the number
of units sold. Did the pro t exceed $4 million on sales
of 380,000units?
(1) The pro t exceeded $2 million on sales of
200,000units.
(2) The pro t exceeded $5 million on sales of
350,000units.
271. If n is an integer, is n even?
(1) n
2 − 1 is an odd integer.
(2) 3 n + 4 is an even integer.
272. Carmen currently works 30 hours per week at her
part‐time job. If her gross hourly wage were to
increaseby $1.50, how many fewer hours could she
work perweek and still earn the same gross weekly
pay asbefore the increase?
(1) Her gross weekly pay is currently $225.00.
(2) An increase of $1.50 would represent an
increase of 20 percent of her current gross
hourly wage.
273. A certain plumber charges $92 for each job completed
in 4hours or less and $23per hour for each job
completed in more than 4hours. If it took the plumber
a total of 7hours to complete two separate jobs, what
was the total amount charged by the plumber for the
two jobs?
(1) The plumber charged $92 for one of the two
jobs.
(2) The plumber charged $138 for one of the two
jobs.
274. If x and y are positive numbers, is +
+>
x
y
x
y
1
1 ?
(1) x > 1
(2) x < y
275. If a and b are positive integers, is <
a
b
9
11?
(1)
a
b < 0.818
(2)
b
a > 1.223
276. Every object in a box is either a sphere or a cube, and
every object in the box is either red or green. How
many objects are in the box?
(1) There are six cubes and ve green objects in
the box.
(2) There are two red spheres in the box.
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6.3 Data Suffi ciency Practice Questions
275
277. If x and y are positive integers, is xy even?
(1) x2 + y2−1 is divisible by 4.
(2) x + y is odd.
278. If a and b are integers, is a+b+3 an odd integer?
(1) ab is an odd integer.
(2) a−b is an even integer.
279. If x and y are positive integers, what is the value of
+xy
?
(1) x + y = 15
(2) =xy 6
280. A certain truck uses +kv
1
12
2 gallons of fuel per mile
when its speed is v miles per hour, where k is a
constant. At what speed should the truck travel so that
it uses 5
12 gallon of fuel per mile?
(1) The value of k is 1
10,800 .
(2) When the truck travels at 30 miles per hour, it
uses 1
6 gallon of fuel per mile.
281. If x = 2 t and =yt
3, what is the value of x
2 − y
2 ?
(1) t
2 −3 = 6
(2) t
3 = –27
282. Last school year, each of the 200 students at a certain
high school attended the school for the entire year.
If there were 8 cultural performances at the school
during the last school year, what was the average
(arithmetic mean) number of students attending each
cultural performance?
(1) Last school year, each student attended at least
one cultural performance.
(2) Last school year, the average number of cultural
performances attended per student was 4.
283. A clothing manufacturer makes jackets that are
wool or cotton or a combination of wool and cotton.
The manufacturer has 3,000pounds of wool and
2,000pounds of cotton on hand. Is this enough wool
and cotton to make at least 1,000jackets?
(1) Each wool jacket requires 4pounds of wool, and
no cotton.
(2) Each cotton jacket requires 6pounds of cotton,
and no wool.
284. Each month, Jim receives a base salary plus a
10percent commission on the price of each car he
sells that month. If Jim sold 15cars last month, what
was the total amount of base salary and commissions
that Jim received that month?
(1) Last month, Jim’s base salary was $3,000.
(2) Last month, Jim sold 3cars whose prices
totaled $60,000 and 5cars whose prices
totaled $120,000.
285. If x is a positive integer greater than 1, what is the
value of x ?
(1) 2 x is a common factor of 18 and 24.
(2) x is a factor of 6.
286. By what percentage was the price of a certain
television set discounted for a sale?
(1) The price of the television set before it was
discounted for the sale was 25 percent greater
than the discounted price.
(2) The price of the television set was discounted by
$60 for the sale.
287. Jack wants to use a circular rug on his rectangular
of ce oor to cover two small circular stains, each
less than
π
100 square feet in area and each more than
3feet from the nearest wall. Can the rug be placed to
cover both stains?
(1) Jack’s rug covers an area of 9π square feet.
(2) The centers of the stains are less than 4 feet apart.
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a×
d
egh
hj
e
f
fa
b
b
c
c
288. In the multiplication table above, each letter represents
an integer. What is the value of c ?
(1) c = f
(2) h≠0
289. If n is an integer, is (0.1)
n greater than (10)
n ?
(1) n > –10
(2) n < 10
290. For a basic monthly fee of F yen (¥ F ), Naoko’s rst
cell phone plan allowed him to use a maximum of
420minutes on calls during the month. Then, for
each of x additional minutes he used on calls, he was
charged ¥ M , making his total charge for the month ¥ T ,
where T = F + xM . What is the value of F ?
(1) Naoko used 450minutes on calls the rst month
and the total charge for the month was ¥13,755.
(2) Naoko used 400minutes on calls the second
month and the total charge for the month was
¥13,125.
291. The weights of all dishes of type X are exactly the
same, and the weights of all dishes of type Y are
exactly the same. Is the weight of 1 dish of type X less
than the weight of 1 dish of type Y ?
(1) The total weight of 3 dishes of type X and
2dishes of type Y is less than the total weight of
2dishes of type X and 4 dishes of type Y.
(2) The total weight of 4 dishes of type X and
3dishes of type Y is less than the total weight of
3dishes of type X and 4 dishes of type Y.
292. If r and t are three-digit positive integers, is r greater
than t ?
(1) The tens digit of r is greater than each of the
three digits of t.
(2) The tens digit of r is less than either of the other
two digits of r.
293. Is the product of two positive integers x and y divisible
by the sum of x and y ?
(1) x=y
(2) x=2
294. A certain high school with a total enrollment of
900students held a science fair for three days last
week. How many of the students enrolled in the high
school attended the science fair on all three days?
(1) Of the students enrolled in the school, 30 percent
attended the science fair on two or more days.
(2) Of the students enrolled in the school, 10 percent
of those that attended the science fair on at
least one day attended on all three days.
295. The average (arithmetic mean) price of the 3 items that
Kate purchased from a clothing store was $50. If there
was no sales tax on any item that had a price of less than
$80 and 6 percent sales tax on all other items, what was
the total sales tax on the 3 items that Kate purchased?
(1) The price of the most expensive item that
Kate purchased from the store was $100.
(2) The price of the least expensive item that
Kate purchased from the store was $10.
296. A company makes and sells two products, P and Q.
The costs per unit of making and selling P and Q
are $8.00 and $9.50, respectively, and the selling
prices per unit of P and Q are $10.00 and $13.00,
respectively. In one month the company sold a total
of 834 units of these products. Was the total pro t on
these items more than $2,000.00 ?
(1) During the month, more units of P than units of Q
were sold.
(2) During the month, at least 100 units of Q were sold.
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6.3 Data Suffi ciency Practice Questions
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297. Jill has applied for a job with each of two different
companies. What is the probability that she will get job
offers from both companies?
(1) The probability that she will get a job offer from
neither company is 0.3.
(2) The probability that she will get a job offer from
exactly one of the two companies is 0.5.
298. A scientist recorded the number of eggs in each of
10birds’ nests. What was the standard deviation of the
numbers of eggs in the 10 nests?
(1) The average (arithmetic mean) number of eggs
for the 10 nests was 4.
(2) Each of the 10 nests contained the same
number of eggs.
299. A conveyor belt moves bottles at a constant speed of
120centimeters per second. If the conveyor belt moves
a bottle from a loading dock to an unloading dock, is
the distance that the conveyor belt moves the bottle
less than 90 meters? (1 meter = 100 centimeters)
(1) It takes the conveyor belt less than 1.2 minutes
to move the bottle from the loading dock to the
unloading dock.
(2) It takes the conveyor belt more than 1.1 minutes
to move the bottle from the loading dock to the
unloading dock.
300. If x, y, and z are positive numbers, what is the value of
the average (arithmetic mean) of x and z ?
(1) x−y = y−z
(2) x2−y2 = z
301. The rectangular rug shown in the gure above has an
accent border. What is the area of the portion of the
rug that excludes the border?
(1) The perimeter of the rug is 44 feet.
(2) The width of the border on all sides is 1 foot.
302. Terry holds 12 cards, each of which is red, white,
green, or blue. If a person is to select a card randomly
from the cards Terry is holding, is the probability less
than 1
2 that the card selected will be either red or white?
(1) The probability that the person will select a blue
card is 1
3.
(2) The probability that the person will select a red
card is 1
6.
303. If y ≠2 xz , what is the value of +
−
xz yz
xz y
2
2 ?
(1) 2 x + y = 3
(2) z = 2
y°
z°
x°
304. In the parallelogram shown, what is the value of x ?
(1) y = 2 x
(2) x + z = 120
305. In a product test of a common cold remedy, x percent
of the patients tested experienced side effects from
the use of the drug and y percent experienced relief
of cold symptoms. What percent of the patients
tested experienced both side effects and relief of cold
symptoms?
(1) Of the 1,000patients tested, 15percent
experienced neither side effects nor relief of
cold symptoms.
(2) Of the patients tested, 30percent experienced
relief of cold symptoms without side effects.
306. Is x < 5 ?
(1) x2 > 5
(2) x2 + x < 5
307. Is 4
x + y
= 8
10 ?
(1) x − y = 9
(2)
=
y
x
1
4
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308. Is zp negative?
(1) pz
4 < 0
(2) p + z
4 = 14
309. In each game of a certain tournament, a contestant
either loses 3 points or gains 2 points. If Pat had
100 points at the beginning of the tournament, how
many games did Pat play in the tournament?
(1) At the end of the tournament, Pat had
104 points.
(2) Pat played fewer than 10 games.
310. At the beginning of the year, the Finance Committee
and the Planning Committee of a certain company
each had n members, and no one was a member of
both committees. At the end of the year, 5 members
left the Finance Committee and 3 members left the
Planning Committee. How many members did the
Finance Committee have at the beginning of the year?
(1) The ratio of the total number of members who
left at the end of the year to the total number of
members at the beginning of the year was 1:6.
(2) At the end of the year, 21 members remained on
the Planning Committee.
311. Can a certain rectangular sheet of glass be positioned
on a rectangular tabletop so that it covers the entire
tabletop and its edges are parallel to the edges of the
tabletop?
(1) The tabletop is 36 inches wide by 60 inches
long.
(2) The area of one side of the sheet of glass is
2,400square inches.
312. In a random sample of 80 adults, how many are
college graduates?
(1) In the sample, the number of adults who are not
college graduates is 3 times the number who are
college graduates.
(2) In the sample, the number of adults who are not
college graduates is 40 more than the number
who are college graduates.
313. Max purchased a guitar for a total of $624, which
consisted of the price of the guitar and the sales tax.
Was the sales tax rate greater than 3 percent?
(1) The price of the guitar that Max purchased was
less than $602.
(2) The sales tax for the guitar that Max purchased
was less than $30.
314. What is the sum of a certain pair of consecutive odd
integers?
(1) At least one of the integers is negative.
(2) At least one of the integers is positive.
315. If a < x < b and c < y < d , is x < y ?
(1) a < c
(2) b < c
316. How many people are directors of both Company K
and Company R ?
(1) There were 17 directors present at a joint
meeting of the directors of Company K and
Company R, and no directors were absent.
(2) Company K has 12 directors and Company R
has 8 directors.
317. The sum of 4 different odd integers is 64. What is the
value of the greatest of these integers?
(1) The integers are consecutive odd numbers.
(2) Of these integers, the greatest is 6 more than
the least.
318. Was the number of books sold at Bookstore X last
week greater than the number of books sold at
Bookstore Y last week?
(1) Last week, more than 1,000 books were sold
at Bookstore X on Saturday and fewer than
1,000books were sold at Bookstore Y on
Saturday.
(2) Last week, less than 20 percent of the books
sold at Bookstore X were sold on Saturday
and more than 20 percent of the books sold at
Bookstore Y were sold on Saturday.
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6.3 Data Suffi ciency Practice Questions
279
319. From May 1 to May 30 in the same year, the balance in
a checking account increased. What was the balance in
the checking account on May 30 ?
(1) If, during this period of time, the increase in
the balance in the checking account had been
12percent, then the balance in the account on
May 30 would have been $504.
(2) During this period of time, the increase in the
balance in the checking account was 8 percent.
320. If x and y are positive, is x < 10 < y ?
(1) x < y and xy = 100
(2) x
2 < 100 < y
2
321. A merchant discounted the sale price of a coat and the
sale price of a sweater. Which of the two articles of
clothing was discounted by the greater dollar amount?
(1) The percent discount on the coat was
2percentage points greater than the percent
discount on the sweater.
(2) Before the discounts, the sale price of the coat
was $10 less than the sale price of the sweater.
322. A taxi company charges f cents for the rst mile of
the taxi ride and m cents for each additional mile. How
much does the company charge for a 10‐mile taxi ride?
(1) The company charges $0.90 for a 2‐mile ride.
(2) The company charges $1.20 for a 4‐mile ride.
323. If the positive integer n is added to each of the
integers 69, 94, and 121, what is the value of n ?
(1) 69 + n and 94 + n are the squares of two
consecutive integers.
(2) 94 + n and 121 + n are the squares of two
consecutive integers.
324. Guy’s net income equals his gross income minus his
deductions. By what percent did Guy’s net income
change on January 1, 1989, when both his gross
income and his deductions increased?
(1) Guy’s gross income increased by 4 percent on
January 1, 1989.
(2) Guy’s deductions increased by 15 percent on
January 1, 1989.
325. If the ratio of the number of teachers to the number of
students is the same in School District M and School
District P, what is the ratio of the number of students in
School District M to the number of students in School
District P ?
(1) There are 10,000 more students in School
DistrictM than there are in School District P.
(2) The ratio of the number of teachers to the
number of students in School District M is
1to20.
326. For a certain city’s library, the average cost of
purchasing each new book is $28. The library
receives $15,000 from the city each year; the library
also receives a bonus of $2,000 if the total number
of items checked out over the course of the year
exceeds 5,000. Did the library receive the bonus last
year?
(1) The library purchased an average of 50new
books each month last year and received enough
money from the city to cover this cost.
(2) The lowest number of items checked out in one
month was 459.
327. Each gift certi cate sold yesterday by a certain
bookstore cost either $10 or $50. If yesterday the
bookstore sold more than 5 gift certi cates that
cost $50 each, what was the total number of gift
certi cates sold yesterday by the bookstore?
(1) Yesterday the bookstore sold fewer than 10 gift
certi cates that cost $10 each.
(2) The total cost of gift certi cates sold yesterday
by the bookstore was $460.
328. What is the tens digit of positive integer x ?
(1) x divided by 100 has a remainder of 30.
(2) x divided by 110 has a remainder of 30.
329. Three dice, each of which has its 6sides numbered
1 through 6, are tossed. The sum of the 3numbers that
are facing up is 12. Is at least 1 of these numbers 5?
(1) None of the 3numbers that are facing up is
divisible by 3.
(2) Of the numbers that are facing up, 2, but not all
3, are equal.
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330. On the number line, point R has coordinate r and
point T has coordinate t . Is t <0?
(1) –1 < r < 0
(2) The distance between R and T is equal to r
2 .
331. S is a set of points in the plane. How many distinct
triangles can be drawn that have three of the points in
S as vertices?
(1) The number of distinct points in S is 5.
(2) No three of the points in S are collinear.
332. Stores L and M each sell a certain product at a
different regular price. If both stores discount their
regular price of the product, is the discount price at
Store M less than the discount price at Store L ?
(1) At Store L the discount price is 10 percent less
than the regular price; at Store M the discount
price is 15 percent less than the regular price.
(2) At Store L the discount price is $5 less than the
regular store price; at Store M the discount price
is $6 less than the regular price.
333. If d denotes a decimal, is d ≥ 0.5 ?
(1) When d is rounded to the nearest tenth, the
result is 0.5.
(2) When d is rounded to the nearest integer, the
result is 1.
334. In the two-digit integers 3■ and 2▲, the symbols ■
and ▲ represent different digits, and the product
(3■)(2▲) is equal to 864. What digit does ■ represent?
(1) The sum of ■ and ▲ is 10.
(2) The product of ■ and ▲ is 24.
M
335. Two points, N and Q (not shown), lie to the right of
point M on line ℓ. What is the ratio of the length of QN
to the length of MQ ?
(1) Twice the length of MN is 3 times the length
of MQ .
(2) Point Q is between points M and N .
336. Did the sum of the prices of three shirts exceed $60 ?
(1) The price of the most expensive of the shirts
exceeded $30.
(2) The price of the least expensive of the shirts
exceeded $20.
337. What is the total number of coins that Bert and
Clairehave?
(1) Bert has 50 percent more coins than Claire.
(2) The total number of coins that Bert and Claire
have is between 21 and 28.
338. A telephone station has x processors, each of which
can process a maximum of y calls at any particular
time, where x and y are positive integers. If 500 calls
are sent to the station at a particular time, can the
station process all of the calls?
(1) x = 600
(2) 100 < y < 200
Price per Flower
Roses $1.00
Daisies $0.50
339. Kim and Sue each bought some roses and some
daisies at the prices shown above. If Kim bought the
same total number of roses and daisies as Sue, was
the price of Kim’s purchase of roses and daisies higher
than the price of Sue’s purchase of roses and daisies?
(1) Kim bought twice as many daisies as roses.
(2) Kim bought 4 more roses than Sue bought.
340. Jazz and blues recordings accounted for 6 percent of
the $840 million revenue from the sales of recordings in
Country Y in 2000. What was the revenue from the sales
of jazz and blues recordings in Country Y in 1998 ?
(1) Jazz and blues recordings accounted for
5 percent of the revenue from the sales of
recordings in Country Y in 1998.
(2) The revenue from the sales of jazz and blues
recordings in Country Y increased by 40 percent
from 1998 to 2000.
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6.3 Data Suffi ciency Practice Questions
281
341. On a certain nonstop trip, Marta averaged x miles per
hour for 2 hours and y miles per hour for the remaining
3hours. What was her average speed, in miles per
hour, for the entire trip?
(1) 2 x + 3 y = 280
(2) y = x + 10
342. If x is a positive integer, what is the value of
+−xx24 ?
(1)
x is an integer.
(2) +x24 is an integer.
343. A tank is lled with gasoline to a depth of exactly
2feet. The tank is a cylinder resting horizontally on
its side, with its circular ends oriented vertically. The
inside of the tank is exactly 6 feet long. What is the
volume of the gasoline in the tank?
(1) The inside of the tank is exactly 4 feet in
diameter.
(2) The top surface of the gasoline forms a
rectangle that has an area of 24 square feet.
qrst
344. Of the four numbers represented on the number line
above, is r closest to zero?
(1) q = – s
(2) – t < q
345. A group consisting of several families visited an
amusement park where the regular admission fees
were ¥5,500 for each adult and ¥4,800 for each child.
Because there were at least 10people in the group,
each paid an admission fee that was 10% less than the
regular admission fee. How many children were in the
group?
(1) The total of the admission fees paid for the
adults in the group was ¥29,700.
(2) The total of the admission fees paid for the
children in the group was ¥4,860 more than the
total of the admission fees paid for the adults in
the group.
ADC
B
x°
346. What is the area of triangular region ABC above?
(1) The product of BD and AC is 20.
(2) x = 45
347. In the xy ‐coordinate plane, is point R equidistant from
points (–3,–3) and (1,–3) ?
(1) The x ‐coordinate of point R is –1.
(2) Point R lies on the line y = –3.
348. What is the ratio of the average (arithmetic mean)
height of students in class X to the average height of
students in class Y ?
(1) The average height of the students in class X is
120 centimeters.
(2) The average height of the students in class X
and class Y combined is 126 centimeters.
349. Is the positive two‐digit integer N less than 40 ?
(1) The units digit of N is 6 more than the tens digit.
(2) N is 4 less than 4 times the units digit.
350. If 2
x + y
= 4
8 , what is the value of y ?
(1) x
2 = 81
(2) x − y = 2
351. Each week a certain salesman is paid a xed amount
equal to $300, plus a commission equal to 5 percent
of the amount of his sales that week over $1,000.
What is the total amount the salesman was paid last
week?
(1) The total amount the salesman was paid last
week is equal to 10 percent of the amount of his
sales last week.
(2) The salesman’s sales last week totaled $5,000.
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352. At a bakery, all donuts are priced equally and all bagels
are priced equally. What is the total price of 5 donuts
and 3 bagels at the bakery?
(1) At the bakery, the total price of 10 donuts and
6bagels is $12.90.
(2) At the bakery, the price of a donut is $0.15 less
than the price of a bagel.
C
B
A
D
353. In the gure above, is the area of triangular region ABC
equal to the area of triangular region DBA ?
(1) ( AC )
2 = 2( AD )
2
(2)
Δ ABC is isosceles.
354. If r and s are positive integers, can the fraction r
s be
expressed as a decimal with only a nite number of
nonzero digits?
(1) s is a factor of 100.
(2) r is a factor of 100.
355. If r > 0 and s > 0, is <
r
s
s
r ?
(1) =
r
s3
1
4
(2) s = r + 4
356. If k is an integer such that 56 < k < 66, what is the
value of k ?
(1) If k were divided by 2, the remainder would be 1.
(2) If k + 1 were divided by 3, the remainder would
be 0.
357. If x is a positive integer, then is x prime?
(1) 3 x + 1 is prime.
(2) 5 x + 1 is prime.
k , n , 12, 6, 17
358. What is the value of n in the list above?
(1) k < n
(2) The median of the numbers in the list is 10.
359. If x and y are integers, what is the value of x + y ?
(1)
<+<
xy
324
(2) 2 < x < y < 5
360. Last year, if Arturo spent a total of $12,000 on his
mortgage payments, real estate taxes, and home
insurance, how much did he spend on his real estate
taxes?
(1) Last year, the total amount that Arturo spent on
his real estate taxes and home insurance was
3
31
3percent of the amount that he spent on his
mortgage payments.
(2) Last year, the amount that Arturo spent on his
real estate taxes was 20 percent of the total
amount he spent on his mortgage payments and
home insurance.
361. If a, b, c, and d are positive numbers, is <
a
b
c
d ?
(1)
<−
−
ca
db
0
(2)
⎛
⎝
⎜⎞
⎠
⎟<
ad
bc
ad
bc
2
362. Is the number of members of Club X greater than the
number of members of Club Y ?
(1) Of the members of Club X, 20 percent are also
members of Club Y.
(2) Of the members of Club Y, 30 percent are also
members of Club X.
qprst
363. On the number line above, p , q , r , s , and t are ve
consecutive even integers in increasing order. What is
the average (arithmetic mean) of these ve integers?
(1) q + s = 24
(2) The average (arithmetic mean) of q and r is 11.
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6.3 Data Suffi ciency Practice Questions
283
364. If ⎡
⎢⎤
⎥
x denotes the least integer greater than or equal
to x , is ⎡
⎢⎤
⎥=x0?
(1) −1 < x < 1
(2) x < 0
365. If x and y are integers, is x > y ?
(1) x + y > 0
(2) y
x < 0
366. If r and s are the roots of the equation x
2 + bx + c = 0,
where b and c are constants, is rs < 0 ?
(1) b < 0
(2) c < 0
k ft
k ft
15 ft
15 ft
367. The gure above represents an L ‐shaped garden. What
is the value of k ?
(1) The area of the garden is 189 square feet.
(2) The perimeter of the garden is 60 feet.
368. The only articles of clothing in a certain closet are
shirts, dresses, and jackets. The ratio of the number
of shirts to the number of dresses to the number of
jackets in the closet is 9:4:5, respectively. If there are
more than 7dresses in the closet, what is the total
number of articles of clothing in the closet?
(1) The total number of shirts and jackets in the
closet is less than 30.
(2) The total number of shirts and dresses in the
closet is 26.
QR
PT
S
O
x°
TOTAL EXPENSES FOR THE
FIVE DIVISIONS OF COMPANY H
369. The gure above represents a circle graph of
CompanyH’s total expenses broken down by the
expenses for each of its ve divisions. If O is the center
of the circle and if Company H’s total expenses are
$5,400,000, what are the expenses for Division R ?
(1) x = 94
(2) The total expenses for Divisions S and T are
twice as much as the expenses for Division R.
370. If x is negative, is x < –3 ?
(1) x
2 > 9
(2) x
3 < –9
371. What is the number of cans that can be packed in a
certain carton?
(1) The interior volume of this carton is 2,304 cubic
inches.
(2) The exterior of each can is 6 inches high and has
a diameter of 4 inches.
rst
uvw
xyz
372. Each of the letters in the table above represents one
of the numbers 1, 2, or 3, and each of these numbers
occurs exactly once in each row and exactly once in
each column. What is the value of r ?
(1) v + z = 6
(2) s + t + u + x = 6
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373. Material A costs $3 per kilogram, and Material B
costs $5 per kilogram. If 10 kilograms of Material K
consists of x kilograms of Material A and y kilograms
of MaterialB, is x > y ?
(1) y > 4
(2) The cost of the 10 kilograms of Material K is
less than $40.
374. At what speed was a train traveling on a trip when it
had completed half of the total distance of the trip?
(1) The trip was 460 miles long and took 4 hours to
complete.
(2) The train traveled at an average rate of
115 miles per hour on the trip.
375. Tom, Jane, and Sue each purchased a new house. The
average (arithmetic mean) price of the three houses
was $120,000. What was the median price of the
three houses?
(1) The price of Tom’s house was $110,000.
(2) The price of Jane’s house was $120,000.
376. What is the value of x if x3 < x2 ?
(1) –2 < x < 2
(2) x is an integer greater than –2.
377. For any integers x and y , min( x , y ) and max( x , y )
denote the minimum and the maximum of x and y ,
respectively. For example, min(5, 2) = 2 and
max(5, 2) = 5. For the integer w , what is the value
of min(10, w ) ?
(1) w = max(20, z ) for some integer z
(2) w = max(10, w )
378. A certain bookcase has 2 shelves of books. On the
upper shelf, the book with the greatest number of
pages has 400pages. On the lower shelf, the book
with the least number of pages has 475 pages. What
is the median number of pages for all of the books on
the 2 shelves?
(1) There are 25 books on the upper shelf.
(2) There are 24 books on the lower shelf.
ABCD
E
379. In the gure above, points A , B , C , D , and E lie on a
line. A is on both circles, B is the center of the smaller
circle, C is the center of the larger circle, D is on the
smaller circle, and E is on the larger circle. What is the
area of the region inside the larger circle and outside
the smaller circle?
(1) AB = 3 and BC = 2
(2) CD = 1 and DE = 4
380. In planning for a car trip, Joan estimated both the
distance of the trip, in miles, and her average speed,
in miles per hour. She accurately divided her estimated
distance by her estimated average speed to obtain an
estimate for the time, in hours, that the trip would take.
Was her estimate within 0.5 hour of the actual time
that the trip took?
(1) Joan’s estimate for the distance was within
5miles of the actual distance.
(2) Joan’s estimate for her average speed was within
10 miles per hour of her actual average speed.
381. A certain list consists of 3 different numbers. Does the
median of the 3 numbers equal the average (arithmetic
mean) of the 3 numbers?
(1) The range of the 3 numbers is equal to twice the
difference between the greatest number and the
median.
(2) The sum of the 3 numbers is equal to 3 times
one of the numbers.
382. Line ℓ lies in the xy-plane and does not pass through
the origin. What is the slope of line ℓ ?
(1) The x-intercept of line ℓ is twice the y-intercept
of line ℓ.
(2) The x- and y-intercepts of line ℓ are both positive.
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6.3 Data Suffi ciency Practice Questions
285
=−
=+
=+
yax
yx
yxb
5
6
3
383. In the xy ‐plane, the straight‐line graphs of the three
equations above each contain the point ( p , r ). If a and b
are constants, what is the value of b ?
(1) a = 2
(2) r = 17
T
U
W
V
S
Q
PR
384. In the gure above, PQR and STU are identical
equilateral triangles, and PQ = 6. What is the
perimeter of polygon PQWTUVR ?
(1) Triangle SWV has perimeter 9.
(2) VW has length 3.5.
385. The range of the numbers in set S is x , and the range
of the numbers in set T is y . If all of the numbers in set
T are also in set S , is x greater than y ?
(1) Set S consists of 7 numbers.
(2) Set T consists of 6 numbers.
386. The hypotenuse of a right triangle is 10 cm. What is
the perimeter, in centimeters, of the triangle?
(1) The area of the triangle is 25 square
centimeters.
(2) The 2 legs of the triangle are of equal length.
Shipment S1 S2 S3 S4 S5 S6
Fraction of the
Total Value of the
Six Shipments
1
4
1
5
1
6
3
20
2
15
1
10
387. Six shipments of machine parts were shipped from a
factory on two trucks, with each shipment entirely on
one of the trucks. Each shipment was labeled either
S1, S2, S3, S4, S5, or S6. The table shows the value
of each shipment as a fraction of the total value of
the six shipments. If the shipments on the rst truck
had a value greater than 1
2 of the total value of the
six shipments, was S3 shipped on the rst truck?
(1) S2 and S4 were shipped on the rst truck.
(2) S1 and S6 were shipped on the second truck.
388. If x , y , and z are three‐digit positive integers and if
x = y + z , is the hundreds digit of x equal to the sum
of the hundreds digits of y and z ?
(1) The tens digit of x is equal to the sum of the
tensdigits of y and z .
(2) The units digit of x is equal to the sum of the
unitsdigits of y and z .
Favorable Unfavorable Not Sure
Candidate M 40 20 40
Candidate N 30 35 35
389. The table above shows the results of a survey of
100voters who each responded “Favorable” or
“Unfavorable” or “Not Sure” when asked about their
impressions of Candidate M and of Candidate N.
What was the number of voters who responded
“Favorable” for both candidates?
(1) The number of voters who did not respond
“Favorable” for either candidate was 40.
(2) The number of voters who responded
“Unfavorable” for both candidates was 10.
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390. A school administrator will assign each student in a group
of n students to one of m classrooms. If 3< m <13< n ,
is it possible to assign each of the n students to one of
the m classrooms so that each classroom has the same
number of students assigned to it?
(1) It is possible to assign each of 3 n students to
one of m classrooms so that each classroom
has the same number of students assigned to it.
(2) It is possible to assign each of 13 n students to
one of m classrooms so that each classroom
has the same number of students assigned to it.
391. If q, s, and t are all different numbers, is q < s < t ?
(1) t−q = |t−s| + |s−q|
(2) t > q
392. What is the median number of employees assigned per
project for the projects at Company Z ?
(1) 25 percent of the projects at Company Z have
4 or more employees assigned to each project.
(2) 35 percent of the projects at Company Z have
2 or fewer employees assigned to each project.
393. Last year, a certain company began manufacturing
product X and sold every unit of product X that it
produced. Last year the company’s total expenses
for manufacturing product X were equal to $100,000
plus 5percent of the company’s total revenue from all
units of product X sold. If the company made a pro t
on productX last year, did the company sell more than
21,000 units of product X last year?
(1) The company’s total revenue from the sale of
product X last year was greater than $110,000.
(2) For each unit of product X sold last year, the
company’s revenue was $5.
394. Beginning in January of last year, Carl made deposits
of $120 into his account on the 15th of each month
for several consecutive months and then made
withdrawals of $50 from the account on the 15th
of each of the remaining months of last year. There
were no other transactions in the account last year. If
the closing balance of Carl’s account for May of last
year was $2,600, what was the range of the monthly
closing balances of Carl’s account last year?
(1) Last year the closing balance of Carl’s account
for April was less than $2,625.
(2) Last year the closing balance of Carl’s account
for June was less than $2,675.
395. Are all of the numbers in a certain list of 15 numbers
equal?
(1) The sum of all the numbers in the list is 60.
(2) The sum of any 3 numbers in the list is 12.
396. If the average (arithmetic mean) of six numbers is 75,
how many of the numbers are equal to 75 ?
(1) None of the six numbers is less than 75.
(2) None of the six numbers is greater than 75.
397. What amount did Jean earn from the commission on
her sales in the rst half of 1988 ?
(1) In 1988 Jean’s commission was 5 percent of the
total amount of her sales.
(2) The amount of Jean’s sales in the second half of
1988 averaged $10,000 per month more than in
the rst half.
A
DB
C
398. In the gure above, if the area of triangular region D is 4,
what is the length of a side of square region A ?
(1) The area of square region B is 9.
(2) The area of square region C is 64
9.
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6.3 Data Suffi ciency Practice Questions
287
399. If n is a positive integer and k = 5.1 × 10
n , what is the
value of k ?
(1) 6,000 < k < 500,000
(2) k
2 = 2.601 × 10
9
x˚
w˚
y˚
z˚
400. What is the value of x + y in the gure above?
(1) w = 95
(2) z = 125
401. If n and k are positive integers, is +>nk n2 ?
(1) k > 3 n
(2) n + k > 3 n
402. In a certain business, production index p is directly
proportional to ef ciency index e , which is in turn directly
proportional to investment index i . What is p if i =70?
(1) e = 0.5 whenever i = 60.
(2) p = 2.0 whenever i = 50.
403. If n is a positive integer, what is the tens digit of n ?
(1) The hundreds digit of 10 n is 6.
(2) The tens digit of n + 1 is 7.
404. What is the value of +−
−
ttx
tx
2?
(1)
−=
t
tx
23
(2) t − x = 5
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231. A
232. C
233. C
234. A
235. C
236. C
237. C
238. B
239. D
240. D
241. C
242. D
243. C
244. E
245. E
246. E
247. D
248. E
249. D
250. D
251. D
252. D
253. D
254. E
255. B
256. D
257. A
258. C
259. C
260. E
261. B
262. C
263. D
264. E
265. C
266. E
267. C
268. E
269. B
270. B
271. D
272. D
273. B
274. B
275. D
276. E
277. D
278. D
279. C
280. D
281. D
282. B
283. C
284. E
285. A
286. A
287. C
288. E
289. E
290. B
291. B
292. C
293. C
294. E
295. A
296. E
297. C
298. B
299. A
300. E
301. E
302. E
303. E
304. D
305. E
306. B
307. C
308. E
309. E
310. D
311. E
312. D
313. A
314. C
315. B
316. C
317. D
318. C
319. C
320. D
321. E
322. C
323. D
324. E
325. E
326. D
327. E
328. A
329. C
330. C
331. C
332. C
333. B
334. D
335. A
336. B
337. C
338. A
339. B
340. B
341. A
342. E
343. D
344. A
345. C
346. A
347. A
348. E
349. D
350. B
351. D
352. A
353. C
354. A
355. D
356. E
357. E
358. C
359. D
360. B
361. B
362. C
363. D
364. C
365. C
366. B
367. A
368. D
369. A
370. A
371. E
372. D
373. B
374. E
375. B
376. B
377. D
378. C
379. D
380. E
381. D
382. A
383. D
384. A
385. E
386. D
387. B
388. A
389. A
390. B
391. A
392. C
393. B
394. C
395. B
396. D
397. E
398. D
399. D
400. C
401. A
402. B
403. A
404. A
6.4 Answer Key
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289
3.2 Diagnostic Test Verbal Questions
B
C
D
20°
A
231. In the gure above, point D is on AC . What is the
degree measure of ∠ BAC ?
(1) The measure of ∠ BDC is 60°.
(2) The degree measure of ∠ BAC is less than the
degree measure of ∠ BCD .
Geometry Angles
(1) Given that the measure of ∠ BDC is 60°,
it follows that the measure of ∠ BDA
is 180°−60°=120°. erefore, since
the measures of the angles in a triangle
add to 180°, the measure of ∠ BAC is
180−(20°+120°)=40°; SUFFICIENT.
(2) Given that the degree measure of ∠ BAC is less
than the degree measure of ∠ BCD , when
the line segmentAC rotates a few degrees
counterclockwise about point A and point D
stays on AC, then the degree measure of
∠ BAC decreases (and the degree measure of
∠ BCD increases, and the degree measure of
∠ ABD remains 20°). erefore, the degree
measure of ∠ BAC can vary; NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
232. A citrus fruit grower receives $15 for each crate of
oranges shipped and $18 for each crate of grapefruit
shipped. How many crates of oranges did the grower
ship last week?
(1) Last week the number of crates of oranges that
the grower shipped was 20 more than twice the
number of crates of grapefruit shipped.
(2) Last week the grower received a total of
$38,700 from the crates of oranges and
grapefruit shipped.
Algebra Simultaneous equations
If x represents the number of crates of oranges
and y represents the number of crates of
grapefruit, nd a unique value for x .
(1) Translating from words into symbols gives
x = 2 y + 20, but there is no information
about y and no way to nd a unique value
for x from this equation. For example, if
y = 10, then x = 40, but if y = 100, then
x = 220; NOT su cient.
(2) Translating from words to symbols gives
15 x+ 18 y = 38,700, but there is no way to
nd a unique value for x from this equation.
For example, if y = 2,150, then x = 0 and if
y = 0, then x = 2,580; NOT su cient.
Taking (1) and (2) together gives a system of two
equations in two unknowns. Substituting the
equation from (1) into the equation from (2) gives
a single equation in the variable y . is equation
can be solved for a unique value of y from which a
unique value of x can be determined.
e correct answer is C;
both statements together are su cient.
6.5 Answer Explanations
The following discussion of data sufficiency is intended to familiarize you with the most efficient and
effective approaches to the kinds of problems common to data sufficiency. The particular questions in
this chapter are generally representative of the kinds of data sufficiency questions you will encounter
on the GMAT exam. Remember that it is the problem solving strategy that is important, not the specific
details of a particular question.
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290
233. A certain mixture of paint requires blue, yellow, and
red paints in ratios of 2:3:1, respectively, and no other
ingredients. If there are ample quantities of the blue and
red paints available, is there enough of the yellow paint
available to make the desired amount of the mixture?
(1) Exactly 20quarts of the mixture are needed.
(2) Exactly 10quarts of the yellow paint are available.
Arithmetic Ratios
Given that the mixture requires blue paint, yellow
paint, and red paint in the ratios 2:3:1, it follows
that 3
231
1
2++= of the mixture will be yellow
paint. Determining whether there is enough yellow
paint available depends on how much of the mixture
is needed and how much yellow paint is available.
(1) is indicates that exactly 20 quarts of the
paint mixture are needed, so 1
2(20)= 10quarts
of yellow paint are needed. However, there
is no information about how much yellow
paint is available; NOT su cient.
(2) is indicates that exactly 10 quarts of
yellow paint are available, but there is no
information about how much of the mixture
or how much yellow paint is needed; NOT
su cient.
Taking (1) and (2) together, 10 quarts of yellow
paint are needed and 10 quarts are available.
e correct answer is C;
both statements together are su cient.
234. If Pat saved $600 of his earnings last month, how
much did Pat earn last month?
(1) Pat spent 1
2 of his earnings last month for living
expenses and saved 1
3 of the remainder.
(2) Of his earnings last month, Pat paid twice as
much in taxes as he saved.
Arithmetic Operations with rational numbers
Let E be Pat’s earnings last month. Find a unique
value for E .
(1) Pat spent E
1
2 for living expenses and so
EEE
1
2
1
2
−=
remained. Pat saved 1
3 of
what remained, so Pat saved EE
1
3
1
2
1
6
⎛
⎝⎞
⎠=.
But Pat saved $600, so E600 1
6
= and this
gives a unique value for E ; SUFFICIENT.
(2) Pat saved $600 last month and paid 2($600)
in taxes, but there is no way to determine
Pat’s earnings last month; NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
O
y
x
R
P
Q
235. In the xy ‐plane above, is angle QPR a right angle?
(1) Points P and Q have the same x ‐coordinate.
(2) Points P and R have the same y ‐coordinate.
Geometry Simple coordinate geometry
(1) Because points P and Q have the same
x ‐coordinate, it follows that side PQ is
vertical (i.e., parallel to the y ‐axis). erefore,
angle QPR will be a right angle if and only if
side PR is horizontal (i.e., parallel to the
x ‐axis). However, depending on the location
of point R in relation to point P , side PR may
or may not be horizontal; NOT su cient.
(2) Because points P and R have the same
y‐ coordinate, it follows that side PR is
horizontal. erefore, angle QPR will be a
right angle if and only if side PQ is vertical.
However, depending on the location of
point Q in relation to point P, side PQ may
or may not be vertical; NOT su cient.
Given (1) and (2), it follows that PQ is vertical
and
PR
is horizontal. erefore, angle QPR is a
right angle.
e correct answer is C;
both statements together are su cient.
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291
6.5 Data Suffi ciency Answer Explanations
236. Each of the marbles in a jar is either red or white or
blue. If one marble is to be selected at random from
the jar, what is the probability that the marble will be
blue?
(1) There are a total of 24 marbles in the jar,
8 of which are red.
(2) The probability that the marble selected will be
white is 1
2.
Arithmetic Probability
is problem can be solved by determining the
number of marbles in the jar and the number that
are blue.
(1) is indicates that there are 24 marbles in
the jar and 8 of them are red. e number
of marbles that are blue is not known; NOT
su cient.
(2) is indicates neither the number of
marbles in the jar nor the number that are
blue; NOT su cient.
Taking (1) and (2) together, there are 24 marbles
in the jar, 8 of which are red and 1
2 (24) = 12 of
which are white. en, the number of blue
marbles is 24−8−12 = 4, and the probability
that one marble selected at random will be blue is
4
24
1
6
=.
e correct answer is C;
both statements together are su cient.
z
w
y
x
237. In the gure above, what is the value of z ?
(1) x = y = 1
(2) w = 2
Geometry Triangles; Pythagorean theorem
(1) Given that x = y =1, the length of the base
of the triangle to the right, which equals
z − y = z −1, can vary, and thus the value of
z can vary; NOT su cient.
(2) Given that w =2, all dimensions of the
rectangle to the left can vary, and thus the
value of z can vary; NOT su cient.
Taking (1) and (2) together, then z = y +( z − y )=
1+( z −1), and the value of z −1 can be
determined by applying the Pythagorean theorem
to the triangle that has hypotenuse of length
w =2 and sides of lengths x =1 and z −1.
Speci cally, the Pythagorean theorem gives
1
2 +( z −1)
2 =2
2 , or 1+( z −1)
2 =4, and solving
this equation gives ( z −1)
2 =3, or z −1= 3, or
z =1+ 3.
e correct answer is C;
both statements together are su cient.
238. Water is pumped into a partially lled tank at a
constant rate through an inlet pipe. At the same time,
water is pumped out of the tank at a constant rate
through an outlet pipe. At what rate, in gallons per
minute, is the amount of water in the tank increasing?
(1) The amount of water initially in the tank is
200gallons.
(2) Water is pumped into the tank at a rate of
10gallons per minute and out of the tank at a
rate of 10 gallons every 21
2 minutes.
Arithmetic Work Problem
If both the rate of the water being pumped into
the tank and the rate of the water being pumped
out of the tank are known, then the rate at which
the total amount of water in the tank is changing
can be determined, but not if only one of these
quantities is known.
(1) is only gives the amount of water in the
tank initially; NOT su cient.
(2) is information provides both the needed
rates. Since the water is being pumped out
of the tank at the rate of 10 gallons every
21
2 minutes, that is, 4 gallons every minute,
and since 10 gallons are pumped into the tank
every minute, the rate at which the water is
increasing in the tank is 10 − 4 = 6 gallons
per minute; SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
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239. What is the value of 10 percent of y ?
(1) 5 percent of y is 60.
(2) y is 80 percent of 1,500.
Arithmetic Percents
is problem can be solved by determining the
value of y .
(1) If 5 percent of y is 60, then 0.05 y = 60 and
y
60
0.05 1, 200== ; SUFFICIENT.
(2) If y is 80 percent of 1,500, then
y = (0.80)(1,500) = 1,200; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
240. What is the cube root of w ?
(1) The 5th root of w is 64.
(2) The 15th root of w is 4.
Arithmetic Operations with radical expressions
Determine the cube root of w , or determine the
value of w
1
3.
(1) Given the 5th root of w is 64,
then w64
1
5= and w64
1
5
5
35
3
⎛
⎝
⎜⎞
⎠
⎟=.
Since ww w,
1
5
5
31
5
5
3
1
3
⎛
⎝
⎜⎞
⎠
⎟==
⎛
⎝
⎜⎞
⎠
⎟⎛
⎝
⎜⎞
⎠
⎟
then w64 64 4
1
3
5
3
1
3
5
5
=⎛
⎝
⎜⎞
⎠
⎟=⎛
⎝
⎜⎞
⎠
⎟=;
SUFFICIENT.
(2) Given the 15th root of w is 4, then w4
1
15 =
wand 4
1
15
5
5
⎛
⎝
⎜⎞
⎠
⎟=. Since www
1
15
55
15
1
3
⎛
⎝
⎜⎞
⎠
⎟==
,
then w4
1
35
=; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
241. If sequence S has 120 terms, what is the 105th
term of S ?
(1) The rst term of S is –8.
(2) Each term of S after the rst term is 10 more
than the preceding term.
Arithmetic Sequences
is problem can be solved by determining at
least one term of the sequence and how each term
is derived from the preceding term(s).
(1) is indicates that the rst term of the
sequence is –8, but does not indicate
how subsequent terms are derived;
NOT su cient.
(2) is indicates how each term is derived
from the preceding term, but does not
indicate at least one term of the sequence;
NOT su cient.
Taking (1) and (2) together, the rst term is –8
and each subsequent term is 10 more than the
preceding term from which the 105th term can
be determined.
e correct answer is C;
both statements together are su cient.
242. The number of seats in the rst row of an auditorium
is 18 and the number of seats in each row thereafter
is 2more than in the previous row. What is the total
number of seats in the rows of the auditorium?
(1) The number of rows of seats in the auditorium
is 27.
(2) The number of seats in the last row is 70.
Arithmetic Sequences and series
Determine the number of seats in the auditorium.
It is given that the rst row has 18 seats, and
since each row after the rst row has 2 more
seats than the previous row, the second row has
20 seats, the third row has 22seats, and so on.
e total number of seats in the auditorium can
be determined if and only if the number of rows
in the auditorium can be determined.
(1) e number of rows is given to be 27, so the
total number of seats can be determined;
SUFFICIENT.
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6.5 Data Suffi ciency Answer Explanations
(2) e last row has 70 seats. Let n be the
number of rows in the auditorium. Since
the rst row has 18 seats, the second row
has 18 + 2 = 20 seats, and the third row has
20 + 2 = 18 + 2(2) = 22 seats, it follows that
the n th row has 18 + ( n −1)(2) seats. en
n
n
n
n
1
8( 1)(2) 70
18 2 2 70
254
27
+− =
+−=
=
=
us the number of rows can be
determined; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
243. If u > 0 and v > 0, which is greater, u
v or v
u ?
(1) u = 1
(2) v > 2
Arithmetic Exponents
(1) Given that u =1, then u
v =1
v =1 and
v
u = v
1 = v . If v =2, then u
v =1 is less than
v
u =2. However, if v =0.5, then u
v =1 is
greater than v
u =0.5; NOT su cient.
(2) Given that v >2, it is possible that u
v
is less than v
u (for example, if u =1 and
v =4, then u
v =1
4 =1 and v
u =4
1 =4),
and it is possible that u
v is greater than
v
u (for example, if u =3 and v =4, then
u
v =3
4 =81 and v
u =4
3 =64);
NOT su cient.
Taking (1) and (2) together, it follows from (1)
that u
v =1 and v
u = v , and it follows from (2)
that v >2. erefore, u
v =1<2< v = v
u , and so
v
u is greater than u
v
.
e correct answer is C;
both statements together are su cient.
244. What was the range of the selling prices of the
30 wallets sold by a certain store yesterday?
(1)
1
3 of the wallets had a selling price of $24 each.
(2) The lowest selling price of the wallets was 1
3 the
highest selling price of the wallets.
Arithmetic Statistics
Since the range of a data set is the greatest value
in the data set minus the least value in the data
set, this problem can be solved if the least selling
price and the greatest selling price of the wallets
sold by the store yesterday can be determined.
(1) is indicates that 10 of the wallets had
a selling price of $24 each, but does not
indicate the least selling price or the greatest
selling price of the wallets sold by the store
yesterday; NOT su cient.
(2) is indicates that L = 1
3 G , where L
represents the least selling price and G
represents the greatest selling price, but does
not give enough information to determine
G − L ; NOT su cient.
Taking (1) and (2) together, the least and greatest
selling prices of the wallets sold by the store
yesterday could be $10 and $30 for a range of
$30−$10 = $20, or the least and greatest
selling prices of the wallets sold by the store
yesterday could be $20 and $60 for a range
of $60−$20 = $40.
e correct answer is E;
both statements together are still not su cient.
245. Three houses are being sold through a real estate
agent. What is the asking price for the house with the
second‐largest asking price?
(1) The difference between the greatest and the
least asking price is $130,000.
(2) The difference between the two greater asking
prices is $85,000.
Algebra Simultaneous equations
Let x , y , and z , where x ≤ y ≤ z , be the asking
prices of the three houses. is problem can be
solved by determining the value of y .
(1) is indicates that z − x = $130,000, but
does not give the value of y ; NOT su cient.
(2) is indicates that z − y = $85,000, but does
not give the value of y ; NOT su cient.
Taking (1) and (2) together, x , y , and z could be
$100,000, $145,000, and $230,000, respectively,
in which case the second highest selling price is
$145,000, or they could be $200,000, $245,000,
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and $330,000, respectively, in which case the
second highest selling price is $245,000.
e correct answer is E;
both statements together are still not su cient.
246. Is rw = 0 ?
(1) –6 < r < 5
(2) 6 < w < 10
Algebra Inequalities
is problem can be solved if it can be
determined that either or both of r and w is zero
or that neither r nor w is zero.
(1) is indicates that r can be, but does not
have to be, zero and gives no indication of
the value of w ; NOT su cient.
(2) is indicates that w cannot be zero, but
gives no indication of the value of r ;
NOT su cient.
Taking (1) and (2) together, r could be zero,
in which case rw = 0 or r could be nonzero, in
which case rw ≠ 0.
e correct answer is E;
both statements together are still not su cient.
247. Is xy
1
=?
(1) xy = 1
(2)
xy
11=
Algebra Equations
(1) is indicates that neither x nor y can be
zero because if x = 0 or y = 0, then xy = 0.
Since xy = 1 and y ≠ 0, then dividing both
sides by y gives xy
1
=; SUFFICIENT.
(2) is indicates that neither x nor y can
be zero because if x = 0 or y = 0, then
xy = 0, and division by zero is unde ned.
Multiplying both sides of the equation
xy
11= by x gives y
1 = x ; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
248. How many people in a group of 50 own neither a fax
machine nor a laser printer?
(1) The total number of people in the group who
own a fax machine or a laser printer or both is
less than 50.
(2) The total number of people in the group who own
both a fax machine and a laser printer is 15.
Algebra Sets
(1) is indicates that the total number who
own either a fax machine or a laser printer
or both is less than 50, but does not indicate
how much less than 50 the total number is.
us, the number of people in the group
who own neither a fax machine nor a laser
printer cannot be determined;
NOT su cient.
(2) is indicates that, of the 50 people, 15 own
both a fax machine and a laser printer, but
does not indicate how many own one or the
other. us, the number of people in the
group who own neither a fax machine nor a
laser printer cannot be determined;
NOT su cient.
Taking (1) and (2) together, it is known that
15 people own both a fax machine and a laser
printer and that the total number who own either
a fax machine or a laser printer or both is less than
50, but the exact number who own neither still
cannot be determined. For example, if 20 people
own only a fax machine and 10 people own only
a laser printer, then both (1) and (2) are true and
the number of people who own neither a fax
machine nor a laser printer is 50−20−10−15 = 5.
However, if 10people own only a fax machine
and 10 people own only a laser printer, then both
(1) and (2) are true and the number of people
who own neither a fax machine nor a laser printer
is 50−10−10−15 = 15.
e correct answer is E;
both statements together are still not su cient.
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295
6.5 Data Suffi ciency Answer Explanations
249. What is the value of w
–2 ?
(1) w
–1 = 1
2
(2) w
3 = 8
Algebra Exponents
(1) Since w
–1 = 1
2, then ( w
–1 )
2 = 1
2
2
⎛
⎝⎞
⎠ = 1
4 or
w
–2 = 1
4; SUFFICIENT.
(2) Since w
3 = 8, then w = 8
3 = 2 and
w
–2 = 2
–2 = 1
4; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
250. A certain investment earned a xed rate of 4 percent
interest per year, compounded annually, for ve years.
The interest earned for the third year of the investment
was how many dollars greater than that for the rst year?
(1) The amount of the investment at the beginning of
the second year was $4,160.00.
(2) The amount of the investment at the beginning of
the third year was $4,326.40.
Arithmetic Applied problems; Percents
is problem can be solved by determining
the dollar amount of the interest earned for
the third year minus the dollar amount of
interest earned in the rst year, or, in symbols,
[ A (1.04)
3 − A (1.04)
2 ]−[ A (1.04)
1 − A ], where A
represents the dollar amount of the investment.
is can be determined if the value of A can be
determined.
(1) is indicates that A (1.04)
1 = $4,160.00, since
the amount of the investment at the beginning
of the second year is the same as the amount
of the investment at the end of the rst year.
us, the value of A can be determined by
dividing 4,160.00 by 1.04; SUFFICIENT.
(2) is indicates that A (1.04)
2 = $4,326.40,
since the amount of the investment at the
beginning of the third year is the same as
the amount of the investment at the end of
the second year. us, the value of A can be
determined by dividing 4,326.40 by (1.04)
2 ;
SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
251. On a recent trip, Mary drove 50 miles. What was the
average speed at which she drove the 50 miles?
(1) She drove 30 miles at an average speed of
60miles per hour and then drove the remaining
20miles at an average speed of 50 miles
per hour.
(2) She drove a total of 54 minutes.
Arithmetic Rate problem
Mary drove 50 miles. Determine the average
speed at which she drove the 50 miles.
If the time it took Mary to drive the 50 miles
can be determined, then her average speed can
be determined: distance = speed × time, or
distance
speed =time
.
(1) It is given that she drove the rst 30 miles
at an average speed of 60 miles per hour, so
she drove the rst 30 miles in 30
60
1
2
= hour.
It is also given that she drove the remaining
20 miles at an average speed of 50 miles per
hour, so she drove the remaining 20 miles in
20
50
2
5
= hours. us, she drove the 50 miles
in a total of 1
2
2
5
9
10
+= hours, and thus
her average speed for the 50 miles can be
determined; SUFFICIENT.
(2) It is given that she drove a total of 54 minutes,
and thus her average speed for the 50 miles
can be determined; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
252. What is the value of t ?
(1) s + t = 6 + s
(2) t
3 = 216
Algebra Equations
(1) Given that s + t =6+ s , subtracting s from
both sides gives t =6; SUFFICIENT.
(2) Given that t
3 =216, taking the cube root of
both sides gives t =6; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
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253. For a certain car repair, the total charge consisted of
a charge for parts, a charge for labor, and a 6 percent
sales tax on both the charge for parts and the charge
for labor. If the charge for parts, excluding sales tax,
was $50.00, what was the total charge for the repair?
(1) The sales tax on the charge for labor was $9.60.
(2) The total sales tax was $12.60.
Arithmetic Applied problems; Percents
To nd the total charge, T , for the repair,
requires determining the value, in dollars,
of T =(1.06)(50+ L ) = 53+1.06 L , where
L represents the charge, in dollars, for labor.
is value can be determined if the value
of L can be determined.
(1) is indicates that 0.06 L = 9.60, from
which L can be determined by dividing
9.60 by 0.06; SUFFICIENT.
(2) is indicates that (0.06)(50 + L ) = 12.60.
So, 3.00 + 0.06 L = 12.60 or 0.06 L = 9.60,
which is the same as the equation in (1);
SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
254. George has a total of B books in his library, 25 of
which are hardcover ction books. What is the
value of B ?
(1) 40 of the B books are ction and the rest are
non ction.
(2) 60 of the B books are hardcovers and the rest
are paperbacks.
Arithmetic Applied problems
e diagram below incorporates the given
information that George has a total of B books,
of which 25 are both ction and hardcover. In the
diagram, x represents the number of books that
are ction and not hardcover, and y represents
the number of books that are hardcover and not
ction.
ction hardcover
25
B – x – 25 – y
yx
(1) Given that 40 of the books are ction, it
follows that x +25=40, or x =15. Using
this additional information, the diagram
(shown below) clearly shows that the value
of B cannot be determined. For example,
y =35 and B =80 is possible (note that
B −40− y =5), and y =35 and B =100 is
possible (note that B −40− y =25);
NOT su cient.
ction hardcover
25
B – 40 – y
y15
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297
6.5 Data Suffi ciency Answer Explanations
(2) Given that 60 of the books are hardcover,
it follows that 25+ y =60, or y =35. Using
this additional information, the diagram
(shown below) clearly shows that the value
of B cannot be determined. For example,
x =15 and B =80 is possible (note that
B − x −60=5), and x =15 and B =100 is
possible (note that B − x −60=25);
NOT su cient.
ction hardcover
25
B – x – 60
35x
Taking (1) and (2) together, there is still not
enough information to determine the value of B ,
since in the diagram below B =80 is possible and
B =100 is possible.
ction hardcover
25
B – 75
3515
e correct answer is E;
both statements together are still not su cient.
255. Is w + h
4 positive?
(1) h is positive.
(2) w is positive.
Arithmetic Properties of numbers
(1) Given that h is positive, then w + h
4 can be
positive (for example, when w =1 and h =1)
and w + h
4 can be negative (for example,
when w =–2 and h =1);
NOT su cient.
(2) Given that w is positive, then because
h
4 ≥0, it follows that w + h
4 ≥ w +0= w
and thus w + h
4 >0 since w >0;
SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
256. In Mr. Smith’s class, what is the ratio of the number of
boys to the number of girls?
(1) There are 3 times as many girls as boys in
Mr.Smith’s class.
(2) The number of boys is 1
4 of the total number of
boys and girls in Mr. Smith’s class.
Algebra Ratio and proportion
Letting B be the number of boys and G be the
number of girls, determine the value of B
G.
(1) It is given that G = 3 B , so 1
3= B
G;
SUFFICIENT.
(2) It is given that
B
BG
1
4()=+
. erefore,
4 B= B+ G , or 3 B = G , or B
G
1
3
=;
SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
257. If the sequence S has 300 terms, what is the 293rd
term of S ?
(1) The 298th term of S is –616, and each
term of S after the rst is 2 less than the
precedingterm.
(2) The rst term of S is –22.
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298
Arithmetic Sequences and series
Determine the 293rd term of the sequence S ,
or S
293 .
(1) It is given that the 298th term of S is
–616, and each term of S after the rst
term is 2 less than the preceding term.
erefore, S
298 = –616 = S
297 −2, and so
S
297 = –616 + 2 = –614. Similarly,
S
296 , S
295 , S
294 , and S
293 can be determined,
each from the term preceding it;
SUFFICIENT.
(2) It is given that S
1 = –22, but there is no
information on how subsequent terms
are related to S
1 and therefore no way to
determine S
293 ; NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
258. If a is a 3-digit integer and bis a 3-digit integer, is the
units digit of the product of aandb greater than 5 ?
(1) The units digit of a is 4.
(2) The units digit of b is 7.
Arithmetic Operations with integers
Determine whether the units digit of the product
of the two 3-digit integers a and b is greater than 5.
(1) It is given that the units digit of a is 4. If the
units digit of b is 0 or 1, then the units digit
of ab is not greater than 5. However, if the
units digit of b is 2, then the units digit of
ab is greater than 5; NOT su cient.
(2) It is given that the units digit of b is 7. If
the units digit of a is 0, then the units digit
of ab is not greater than 5. However, if the
units digit of a is 1, then the units digit of
ab is greater than 5; NOT su cient.
Taking (1) and (2) together, the units digit of a is
4 and the units digit of b is 7. erefore, the units
digit of ab is 8, which is greater than 5.
e correct answer is C;
both statements together are su cient.
259. In each of the last ve years, Company K donated
p percent of its annual pro ts to a certain scholarship
fund. Did Company K donate more than $10,000 to
the scholarship fund last year?
(1) Two years ago, Company K had annual pro ts
of $3 million and donated $15,000 to the
scholarship fund.
(2) Last year, Company K had annual pro ts of
$2.5million.
Arithmetic Applied problems; Percents
Let $ k be CompanyK’s pro t last year.
Is p
100
⎛
⎝
⎜⎞
⎠
⎟ k >10,000?
(1) Given that p
100
⎛
⎝
⎜⎞
⎠
⎟(3million)=15,000,
it follows that p =(15,000)(100)
3 million
1
2
=.
However, the question cannot be answered
since no information is available about the
value of k . For example, if k =3million, then
p
100
⎛
⎝
⎜⎞
⎠
⎟ k =15,000, and the answer to the
question is yes. However, if k =1million,
then p
100
⎛
⎝
⎜⎞
⎠
⎟ k =5,000, and the answer to the
question is no; NOT su cient.
(2) Given that k =2.5million, it follows that
p
100
⎛
⎝
⎜⎞
⎠
⎟ k = p
100
⎛
⎝
⎜⎞
⎠
⎟(2.5million). However,
the question cannot be answered since no
information is available about the value of p .
For example, if p =1, then p
100
⎛
⎝
⎜⎞
⎠
⎟ k =25,000,
and the answer to the question is yes. However,
if p =0.1, then p
100
⎛
⎝
⎜⎞
⎠
⎟ k =2,500, and the
answer to the question is no; NOT su cient.
Taking (1) and (2) together, the values of both
p and k can be determined. erefore, the value of
p
100
⎛
⎝
⎜⎞
⎠
⎟ k can be determined, and thus the answer
to the question can be determined.
e correct answer is C;
both statements together are su cient.
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299
6.5 Data Suffi ciency Answer Explanations
z
y
x
260. Is the area of the triangular region above less than 20 ?
(1) x2 + y2 ≠ z2
(2) x + y < 13
Geometry Triangles; Area
Determine whether the area of the given triangle
is less than 20.
(1) is indicates the triangle is not a right
triangle but gives no information about the
base and height or how to determine them
in order to nd the area; NOT su cient.
(2) is indicates that two sides of the triangle
have lengths x and y such that x + y < 13. If,
for example, the triangle is a right triangle
with x = 3 and y = 4, then x + y = 3 + 4 =
7 < 13 and the area of the triangle is
1
2(3)(4) = 6, which is less than 20. But if the
triangle is a right triangle with x = y = 42,
then x + y = 42 +42 = 2 42 = 168 <
169 = 13 and the area is 1
2(42)(42)
=
21, which is greater than 20; NOT su cient.
Taking (1) and (2) together, since the triangle is
not a right triangle from (1), the diagrams show
two other possibilities: an obtuse triangle and an
acute triangle.
For the obtuse triangle, h<x since because h is
a leg of a right triangle with hypotenuse x. e
area A is given by A= 1
2yh< 1
2xy. If x=y=6,
then x+y=6+6=12<13 and A< 1
2(62)=18.
e area of the triangular region is less than 20
for the obtuse triangle. For the acute triangle,
if x=y= 42 , then x+y= 42 + 42 =
242 = 168 < 169 =13. Let d=1. en,h2=
(42)
2−1=42−1=41 and h= 41 . us, for
the acute triangle, the area of the triangular region
is yh
1
2= 1
2(42)(41)
and 1
2(42)(41)
>
1
2(40)(40)
or 1
2(42)(41)
>20. erefore,
it is possible that the area of the triangular region
can be less than 20 (in the case of the obtuse
triangle) and it is possible that the area of the
triangular region can be greater than 20 (in the
case of the acute triangle).
e correct answer is E;
both statements together are still not su cient.
261. A , B , C , and D are points on a line. If C is the midpoint
of line segment AB and if D is the midpoint of line
segment CB , is the length of line segment DB greater
than5?
(1) The length of line segment AC is greater than8.
(2) The length of line segment CD is greater than6.
Geometry Lines and segments
It is given that C is the midpoint of AB,
so AC = CB = 1
2( AB ). It is given that D is
the midpoint of CB, so CD = DB =1
2( CB ).
Determine if DB >5.
(1) Given that AC >8, it follows that CB >8
since AC = CB , and so DB =1
2( CB )> 1
2(8)
or DB >4. However, this means that DB
could be 6 and 6>5 or DB could be 4.1 and
4.1<5; NOT su cient.
(2) Given that CD >6, it follows that DB >6
since CD = DB ; SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
262. The people in a line waiting to buy tickets to a show
are standing one behind the other. Adam and Beth
are among the people in the line, and Beth is standing
behind Adam with a number of people between them. If
the number of people in front of Adam plus the number
of people behind Beth is 18, how many people in the
line are behind Beth?
(1) There are a total of 32 people in the line.
(2) 23 people in the line are behind Adam.
hz
x
y
y
x
z
h
d
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Arithmetic Order
Beth is standing in line behind Adam with a
number of people between them. Let x be the
number of people ahead of Adam, let y be the
number of people between Adam and Beth, and
let z be the number of people behind Beth. It is
given that x+z=18. Determine z.
(1) is indicates that there are 32people in
the line. Two of these people are Adam
and Beth, so there are 30 other people in
line besides Adam and Beth. erefore,
x+y+z=30 and x+z=18. From this,
y=12, but z cannot be determined uniquely.
For example, if x=5, then z=13, but if
x=10, then z=8; NOT su cient.
(2) is indicates that y+1+z=23 because
the people behind Adam consist of the
people between Adam and Beth, Beth
herself, and the people behind Beth. If, for
example, y=4, then z=18, but if y=9, then
z= 13; NOT su cient.
Taking (1) and (2) together, y=12 from (1) and
y+z=22 from (2). erefore, z=10, and there
are 10 people in line behind Beth.
e correct answer is C;
both statements together are su cient.
263. Square ABCD is inscribed in circle O . What is the area
of square region ABCD ?
(1) The area of circular region O is 64 π .
(2) The circumference of circle O is 16 π .
Geometry Circles; Area
AB
C
D
Since the area of square ABCD is the square of its
side length, to solve this problem it is necessary
to determine the side length of ABCD . From the
gure, a diameter of the circle coincides with a
diagonal of the square. If the length of a diameter of
the circle can be determined, then the length
of a diagonal of the square can be determined,
from which the side length of the square can be
determined using the Pythagorean theorem.
(1) is indicates that the area of the circle is
64π, so letting r represent the radius of the
circle, π r
2 = 64π. us, r
2 = 64, r = 8, and
d = 2(8) = 16, where d represents the length
of the diameter of the circle and also the
diagonal of the square; SUFFICIENT.
(2) is indicates that the circumference of
the circle is 16π, so letting d represent the
length of the diameter of the circle as well
as the diagonal of the square, π d = 16π.
us, d = 16; SUFFICIENT.
e correct answer is D;
each statement alone is sufficient.
264. Lines k and m are parallel to each other. Is the slope of
line k positive?
(1) Line k passes through the point (3,2).
(2) Line m passes through the point (–3,2).
Geometry Coordinate geometry
(1) is indicates that line k passes through
the point (3,2). One point is not enough
to determine whether the slope of line k is
positive. If, for example, line k also passes
through the point (0,0), then the slope of
line k is 20
30
2
3
−
−=, which is positive. But if
line k also passes through the point (5,0),
then the slope of line k is 20
35
2
2
−
−=−, which
is negative; NOT su cient.
(2) is indicates that line m passes through
the point (–3,2). One point is not enough
to determine whether the slope of line m is
positive. If, for example, line m also passes
through the point (0,0), then the slope of
line m is 20
30
2
3
−
−− =−, which is negative. In
this case, the slope of line k is also negative
since parallel lines k and m have the same
slope. But if line m also passes through the
point (0,5), then the slope of line
m is 25
30
3
3
−
−− =−
−, which is positive.
In this case, the slope of line k is also
positive since parallel lines k and m have the
same slope; NOT su cient.
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301
Taking (1) and (2) together gives no more
information than (1) or (2) alone and so whether
the slope of line k is positive cannot be determined.
e correct answer is E;
both statements together are still not su cient.
265. In cross section, a tunnel that carries one lane of
one‐way traf c is a semicircle with radius 4.2m. Is the
tunnel large enough to accommodate the truck that is
approaching the entrance to the tunnel?
(1) The maximum width of the truck is 2.4m.
(2) The maximum height of the truck is 4m.
Geometry Circles; Pythagorean theorem
(1) Given that the maximum width of the truck
is 2.4m, it is possible that the tunnel is large
enough (for example, if the maximum height
of the truck is su ciently small) and it is
possible that the tunnel is not large enough
(for example, if the maximum height of the
truck is su ciently large); NOT su cient.
(2) Given that the maximum height of the
truck is 4m, it is possible that the tunnel is
large enough (for example, if the maximum
width is su ciently small) and it is possible
that the tunnel is not large enough (for
example, if the maximum width of the truck
is su ciently large); NOT su cient.
Taking (1) and (2) together, it is possible for the
truck to pass through the tunnel, because even
if the truck were rectangular with width 2.4m
and height 4m, the truck could pass through
the tunnel if it were centered in the tunnel as
shown in the diagram. In this position, it follows
from the Pythagorean theorem that every point
on the truck is located at most a distance of
1.2 4
22
()
+meters from the center axis of the
tunnel, and this distance is less than 4.2meters,
the radius of the tunnel, since (1.2)
2 +4
2 =17.44
is less than (4.2)
2 =17.64.
4 m
1.2 m
e correct answer is C;
both statements together are su cient.
266. In a certain group of 50 people, how many are doctors
who have a law degree?
(1) In the group, 36 people are doctors.
(2) In the group, 18 people have a law degree.
z
w
doctors law degree
yx
Arithmetic Sets
Using the labels in the Venn diagram,
w+x+y+z=50. Determine the value of y.
(1) is indicates that x+y=36 but does not
give a unique value for y. For example,
if x=18, then y=18; but if x=10, then
y=26; NOT su cient.
(2) is indicates that y+z=18 but does not
give a unique value for y. For example, if
z=8, then y=10; but if z=10, then y=8;
NOT su cient.
Taking (1) and (2) together, if w=6, x=26,
y=10, and z=8, then w+x+y+z=50,
x+y=36, and y+z=18. In this case, y=10.
However, if w=2, x=30, y=6, and z=12, then
w+x+y+z=50, x+y=36, and y+z=18. In
this case, y=6.
Alternatively, this problem can be solved by
means of a contingency table. Letting n represent
the number of doctors with a law degree, the
table with the given information is shown below.
doctor not a doctor total
law degree n
no law degree
total 50
(1) is indicates that there are 36 doctors,
so the number of people who are not
doctors is 50−36=14. e table with this
information is shown below.
doctor not a doctor total
law degree n
no law degree
total 36 14 50
6.5 Data Suffi ciency Answer Explanations
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It is obvious from the table that there is not
enough information to determine the value of n,
the number of doctors with a law degree; NOT
su cient.
(2) is indicates that there are 18people
with a law degree, so the number of people
without a law degree is 50−18=32. e
table with this information is shown below.
doctor not a doctor total
law degree n18
no law degree 32
total 50
It is obvious from the table that there is not enough
information to determine the value of n, the number
of doctors with a law degree; NOT su cient.
e table with the information from both (1) and
(2) is shown below.
doctor not a doctor total
law degree n18
no law degree 32
total 36 14 50
It is obvious from the table that there is still not
enough information to determine the value of n,
the number of doctors with a law degree.
e correct answer is E;
both statements together are still not su cient.
267. Of a group of 50 households, how many have at least
one cat or at least one dog, but not both?
(1) The number of households that have at least one
cat and at least one dog is 4.
(2) The number of households that have no cats and
no dogs is 14.
z
w
cat dog
yx
Arithmetic Sets
Using the labels on the Venn diagram,
w+x+y+z=50. Determine the value of x+z.
(1) is indicates that y=4, so w+x+z=46,
but the value of x+z cannot be uniquely
determined; NOT su cient.
(2) is indicates that w=14, so x+y+z=36,
but the value of x+z cannot be uniquely
determined; NOT su cient.
Taking (1) and (2) together, 14+x+4+z=50,
so x+z=50−14−4=32.
e correct answer is C;
both statements together are su cient.
268. On a certain date, Hannah invested $5,000 at
x percent simple annual interest and a different amount
at y percent simple annual interest. What amount did
Hannah invest at y percent simple annual interest?
(1) The total amount of interest earned by Hannah’s
two investments in one year was $900.
(2) Hannah invested the $5,000 at 6 percent simple
annual interest.
Algebra Applied problems
Let $ A be the amount that Hannah invested at
y percent. Determine the value of A .
(1) Given that the sum of x
100 ($5,000) and
yA
100 ($ ) is $900, or xAy
5
0100 900+=
, it
is clear that more than one value of A is
possible; NOT su cient.
(2) Given that x = 6, it is clear that more than
one value of A is possible; NOT su cient.
(1) and (2) together are not su cient because
more than one value of A is possible such that
Ay
50(6) 100 900+=
, or Ay = 60,000. For example,
A = 10,000 and y = 6 is possible, and A = 20,000
and y = 3 is also possible.
e correct answer is E;
both statements together are still not su cient.
269. Do at least 60 percent of the students in Pat’s class
walk to school?
(1) At least 60 percent of the female students in
Pat’s class walk to school.
(2) The number of students in Pat’s class who walk
to school is twice the number of students who
do not walk to school.
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303
6.5 Data Suffi ciency Answer Explanations
Arithmetic Percents
is problem can be solved by determining the
total number of students in Pat’s class and the
number who walk to school.
(1) is indicates that at least 60% of the female
students in Pat’s class walk to school. However,
it does not give any information about the
other students in Pat’s class; NOT su cient.
(2) Letting x represent the number of students
in Pat’s class who do not walk to school,
this indicates that 2 x students in Pat’s
class walk to school and that the total
number of students in Pat’s class is
x + 2 x = 3 x . From this, the percent of
students in Pat’s class who walk to school is
x
x
2
3100
⎡
⎣
⎢⎤
⎦
⎥% = 2
3(100)
⎡
⎣
⎢⎤
⎦
⎥%; SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
270. The profit from the sale of a certain appliance
increases, though not proportionally, with the number
of units sold. Did the profit exceed $4 million on sales
of 380,000units?
(1) The pro t exceeded $2 million on sales of
200,000units.
(2) The pro t exceeded $5 million on sales of
350,000units.
Arithmetic Arithmetic operations; Proportions
(1) If the profits did increase proportionally,
it might be reasonable to expect a profit
of $4 million on sales of 400,000 units.
However, it is given that the profits do not
increase proportionally. Without knowing
how the profits increase, it is impossible to
tell the profits on sales of 380,000 units;
NOT sufficient.
(2) It is given that the profits do increase with the
number of units sold. erefore, since the profit
on sales of just 350,000 units well exceeded
$4 million, then sales of 350,000+ 30,000=
380,000units would also have a profit
exceeding $4 million; SUFFICIENT.
e correct answer is B;
statement 2 alone is sufficient.
271. If n is an integer, is n even?
(1) n
2 − 1 is an odd integer.
(2) 3 n + 4 is an even integer.
Arithmetic Properties of numbers
Determine if the integer n is even.
(1) Since n
2 − 1 is odd, n
2 is even and so n is
even; SUFFICIENT.
(2) Since 3 n + 4 is even, 3 n is even and so n is
even; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
272. Carmen currently works 30 hours per week at her
part‐time job. If her gross hourly wage were to
increase by $1.50, how many fewer hours could she
work per week and still earn the same gross weekly
pay as before the increase?
(1) Her gross weekly pay is currently $225.00.
(2) An increase of $1.50 would represent an
increase of 20 percent of her current gross
hourly wage.
Arithmetic Operations with rational numbers
Let w be Carmen’s gross hourly wage and let n be
the number of hours fewer Carmen will need to
work. Find a unique value for n such that
30 w = (30 − n )( w + 1.50).
(1) Since Carmen’s gross weekly pay is
currently $225.00, then 30 w = 225 and
w = 7.50. Substituting 7.50 for w gives
30(7.50)= (30 − n )(7.50 + 1.50), which
can be solved for a unique value of n ;
SUFFICIENT.
(2) Since 1.50 is 20 percent of Carmen’s
current gross hourly pay, 1.50 = 0.20 w and
w = 7.50. is is the same information that
was gained from statement (1) and will lead
to the same result; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
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273. A certain plumber charges $92 for each job completed
in 4hours or less and $23per hour for each job
completed in more than 4hours. If it took the plumber
a total of 7hours to complete two separate jobs, what
was the total amount charged by the plumber for the
two jobs?
(1) The plumber charged $92 for one of the two
jobs.
(2) The plumber charged $138 for one of the two
jobs.
Arithmetic Applied problems
Find the total amount charged for two jobs
lasting a total of 7hours if the plumber charges
$92 for a job lasting 4 hours or less and $23 per
hour for a job lasting more than 4 hours.
(1) is indicates that one of the two jobs lasted
4hours or less. If that job lasted 2hours, then
the other job lasted 5hours, and the charge
for that job would be ($23)(5) =$115, making
the total for the two jobs $92+$115=$207.
However, if the jobs lasted 1hour and
6hours, respectively, then the total charge
for the two jobs would be $92+(6)($23) =
$92+$138=$230; NOT su cient.
(2) is indicates that one job lasted
$138
$23 =6hours. erefore, the other
job lasted for 1 hour and the charge for
that job was $92, making the total charge
for the two jobs $92+$138=$230;
SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
274. If x and y are positive numbers, is +
+>
x
y
x
y
1
1 ?
(1) x > 1
(2) x < y
Algebra Inequalities
Since y is positive, multiplying both sides of
the inequality x
y
x
y
1
1
+
+> by y(y+1) gives
y(x+1)>x(y+1) or xy+y>xy+x, which is
equivalent to y>x. So, determining whether the
inequality x
y
x
y
1
1
+
+> is true is equivalent to
determining whether the inequality y>x is true.
(1) is indicates that x>1. If, for example,
x=3 and y=4, then y>x is true. However,
if x=4 and y=3, then y>x is not true;
NOT su cient.
(2) is indicates thatx<y, so y>x is true;
SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
275. If a and b are positive integers, is <
a
b
9
11?
(1)
a
b < 0.818
(2)
b
a > 1.223.
Arithmetic Inequalities
If 11 a < 9 b and b is positive, then a
b
11 9< and
a
b
9
11
<. erefore, this problem can be solved by
determining if 11 a < 9 b .
(1) From this,
a
b < 0.818 given
a < 0.818 b multiply both sides by b ,
which is positive
11 a < 8.998 b multiply both sides by 11
en, since 8.998 b < 9 b , it follows that 11 a < 9 b ;
SUFFICIENT.
(2) From this,
b
a>1.223 given
b >1.223 a multiply both sides by a , which is
positive
9 b >11.007 a multiply both sides by 9
en, since 11.007 a >11 a , it follows that
9 b >11 a ; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
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276. Every object in a box is either a sphere or a cube, and
every object in the box is either red or green. How
many objects are in the box?
(1) There are six cubes and ve green objects in the
box.
(2) There are two red spheres in the box.
Arithmetic Sets
is problem can be solved using a contingency
table set up as shown below, where T represents
the number to be determined.
cube sphere total
red
green
total T
(1) e following table displays the information
that there are 6cubes and 5green objects:
cube sphere total
red
green 5
total 6 T
It is obvious that there is not enough information
to determine a unique value for T; NOT su cient.
(2) e following table displays the information
that there are 2red spheres:
cube sphere total
red 2
green
total T
It is obvious that there is not enough information
to determine a unique value for T; NOT su cient.
e following table displays the information from
(1) and (2) taken together:
cube sphere total
red 2
green 5
total 6 T
It is obvious that there is still not enough
information to determine a unique value for T.
e correct answer is E;
both statements together are still not su cient.
277. If x and y are positive integers, is xy even?
(1) x2 + y2−1 is divisible by 4.
(2) x + y is odd.
Arithmetic Properties of numbers
Determine whether the product of two positive
integers, x and y, is even.
(1) is indicates that x2+y2−1 is divisible
by 4, so x2+y2−1=4q for some integer q.
en x2+y2=4q+1, which means x2+y2
is odd. Both x2 and y2 cannot be even
because, in that case, their sum would be
even, and both cannot be odd because, in that
case, their sum would also be even. erefore,
one of x2 and y2 is even, and the other is odd.
It follows that one of x or y is even and the
other is odd, so xy is even; SUFFICIENT.
(2) If x+y is odd, then one of x and y is even and
the other is odd because if both were even
or both were odd, the sum would be even. It
follows that xy is even; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
278. If a and b are integers, is a+b+3 an odd integer?
(1) ab is an odd integer.
(2) a−b is an even integer.
Arithmetic Properties of numbers
Determine whether a+b+3 is odd for integers
a and b.
(1) is indicates that, since ab is odd, both a
and b are odd because if one of a or b is even
or both a and b are even, then ab is even.
erefore, a+bis even and a+b+3 is odd;
SUFFICIENT.
(2) is indicates that, since a−b is even, both
a and b are even or both are odd because if
one of them is even and the other is odd,
then a−b is odd. erefore, a+bis even,
and a+b+3 is odd; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
6.5 Data Suffi ciency Answer Explanations
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279. If x and y are positive integers, what is the value of
+xy
?
(1) x + y = 15
(2) =xy 6
Algebra Operations with radicals
(1) From this, if x = 1 and y = 14, then
x + y = 15 and xy114114+=+ =+.
But 14 16 4<=
, so 1 + 14 < 1 + 4 = 5.
However, if x = 9 and y = 6, then x + y = 15
and xy9636+=+=+
. But
642>=
so, 3+ 6 3 2 5>+=; NOT
su cient.
(2) From this, if x = 1 and y = 36, then xy = 6
and xy136167+=+ =+=
.
However, if x = 4 and y = 9, then xy = 6
and xy49235+=+=+=
; NOT
su cient.
Taking (1) and (2) together, x + y = 15 and
xy = 6, so
xx(15 )−=6substitute 15− x for y
x (15− x ) =36 square both sides
15 x − x
2 =36 use distributive property
x
2 −15 x + 36 =0 collect like terms
( x −12)( x −3) =0 factor
us, x = 12 or x = 3. If x = 12, then y = 3 and
x+ y= 12+ 3. If x = 3, then y = 12 and
x+ y= 3+ 12.
Algebraically, if the value of xy
2
()
+=
x2
()
+2xy +y2
()
= x + y +2xy can be
determined, then the value of xy+ can be
determined, and conversely.
(1) From this, xy
2
()
+= x + y + 2xy =
15+2xx(15 )−, but the value of x is
unknown, and the value of xy
2
()
+
cannot be determined; NOT su cient.
(2) From this, xy
2
()
+= x + y + 2xy =
x + x
36+2(6), but the value of x is
unknown, and the value of xy
2
()
+
cannot be determined; NOT su cient.
Taking (1) and (2) together, xy
2
()
+=
x + y + 2xy = 15 + (2)(6) = 27 and
so xy+ = 27 = 33. Note that in the
nonalgebraic solution xy+= 3 +12 and
3 +12= 3+23=33.
e correct answer is C;
both statements together are su cient.
280. A certain truck uses +kv
1
12
2 gallons of fuel per mile
when its speed is v miles per hour, where k is a
constant. At what speed should the truck travel so that
it uses 5
12 gallon of fuel per mile?
(1) The value of k is 1
10,800.
(2) When the truck travels at 30 miles per hour, it
uses 1
6 gallon of fuel per mile.
Algebra Applied problems
is problem can be solved by determining the
positive value of v so that 1
12 + kv
2 = 5
12.
(1) is indicates the value of k and so the
value of v can be determined by solving
1
12 +1
10,800 v
2 =5
12 for v ; SUFFICIENT.
(2) is indicates that 1
12 + k (30)
2 =1
6. e
value of k can be determined by solving
this equation for k . en that value of k
can be substituted into 1
12 + kv
2 = 5
12,
which can then be solved for the value of v ;
SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
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6.5 Data Suffi ciency Answer Explanations
281. If x = 2 t and yt
3
=, what is the value of x
2 − y
2 ?
(1) t
2 −3 = 6
(2) t
3 = –27
Algebra Simplifying algebraic expressions
is problem can be solved by determining the
value of −= −
⎛
⎝⎞
⎠=−xy t ttt
(2 ) 349
22 2
2
22, and
this can be determined if the value of t
2 or the
value of t can be determined.
(1) is indicates that t
2 −3 = 6 and so
t
2 = 6 + 3 = 9; SUFFICIENT.
(2) is indicates that t
3 = –27 and so
t = –3; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
282. Last school year, each of the 200 students at a certain
high school attended the school for the entire year.
If there were 8 cultural performances at the school
during the last school year, what was the average
(arithmetic mean) number of students attending each
cultural performance?
(1) Last school year, each student attended at least
one cultural performance.
(2) Last school year, the average number of
cultural performances attended per student
was 4.
Arithmetic Statistics
Determine the average number of students
attending each of 8cultural performances at a
school that has 200students.
(1) is indicates that each student attended
at least one cultural performance, but the
average number of students attending
each performance cannot be uniquely
determined. It could be as low as
200
8=25students if each student attended
exactly one performance, or it could be as
high as 200
1=200 if each student attended
every performance; NOT su cient.
(2) is indicates that, since the average number
of performances attended per student was
4, total attendance at performances
total number of students =4, so
the total attendance at the performances is
(4)(200)=800students. It follows that the
average number of students attending each
performance is 800
8=100; SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
283. A clothing manufacturer makes jackets that are
wool or cotton or a combination of wool and cotton.
The manufacturer has 3,000pounds of wool and
2,000pounds of cotton on hand. Is this enough wool
and cotton to make at least 1,000jackets?
(1) Each wool jacket requires 4pounds of wool, and
no cotton.
(2) Each cotton jacket requires 6pounds of cotton,
and no wool.
Arithmetic Applied problems
(1) Given that each wool jacket requires
4pounds of wool and no cotton, then at
most a total of 750wool jackets can be
made (because 3,000
4=750), and possibly
no other jackets. erefore, it is possible
that there is enough wool and cotton to
make at least 1,000jackets (for example, if
there is enough cotton to make 250cotton
jackets) and it is possible that there is not
enough wool and cotton to make at least
1,000jackets (for example, if there is less
than the amount of cotton needed to make
250cotton jackets); NOT su cient.
(2) Given that each cotton jacket requires
6pounds of cotton and no wool, then at
most a total of 333cotton jackets can be
made (because rounding 2, 000
6 down to the
nearest integer gives 333), and possibly no
other jackets. erefore, it is possible that
there is enough wool and cotton to make at
least 1,000jackets (for example, if there is
enough wool to make 667wool jackets), and
it is possible that there is not enough wool
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and cotton to make at least 1,000jackets
(for example, if there is less than the amount
of wool needed to make 667wool jackets);
NOT su cient.
Taking (1) and (2) together, there is enough
wool and cotton to make 750wool jackets and
333cotton jackets for a total of 1,083jackets.
e correct answer is C;
both statements together are su cient.
284. Each month, Jim receives a base salary plus a
10percent commission on the price of each car he
sells that month. If Jim sold 15cars last month, what
was the total amount of base salary and commissions
that Jim received that month?
(1) Last month, Jim’s base salary was $3,000.
(2) Last month, Jim sold 3cars whose prices
totaled $60,000 and 5cars whose prices
totaled $120,000.
Arithmetic Applied problems
Determine the total of Jim’s base salary plus a
10% commission on the price of each of the
15cars he sold last month.
(1) is indicates that Jim’s base salary was
$3,000 but gives no information about the
prices of the 15cars he sold last month;
NOT su cient.
(2) is indicates that Jim’s commission on 8cars
that he sold last month can be determined
but gives no information about his base salary
or about the prices of the other 7cars he sold
last month; NOT su cient.
Taking (1) and (2) together gives Jim’s base salary
and information about the prices of 8 of the 15cars
he sold last month, but does not provide information
about the selling prices of the other 7cars he sold.
e correct answer is E;
both statements together are still not su cient.
285. If x is a positive integer greater than 1, what is the
value of x ?
(1) 2 x is a common factor of 18 and 24.
(2) x is a factor of 6.
Arithmetic Properties of numbers
(1) Given that 2 x , where x is an integer greater
than 1, is a common factor of 18 and 24,
then 2 x is an even integer greater than or
equal to 4 that is a factor of 18 and 24. e
factors of 18 are 1, 2, 3, 6, 9, and 18. e
factors of 24 are 1, 2, 3, 4, 6, 8, 12, and 24.
Since the only even integer greater than or
equal to 4 that belongs to both lists is 6, it
follows that 2 x =6, or x =3; SUFFICIENT.
(2) Given that x , an integer greater than 1, is a
factor of 6, then x could be 2, 3, or 6; NOT
su cient.
e correct answer is A;
statement 1 alone is su cient.
286. By what percent was the price of a certain television
set discounted for a sale?
(1) The price of the television set before it was
discounted for the sale was 25 percent greater
than the discounted price.
(2) The price of the television set was discounted by
$60 for the sale.
Arithmetic Percents
Let B represent the price, in dollars, for the
television before the sale and let D represent the
discounted price, in dollars. e percent by which
B was discounted to obtain D can be determined
if the value of −BD
B can be determined.
(1) is indicates that B is 25% greater
than D or that B = 1.25 D . en,
−=−==
BD
B
DD
D
1.25
1.25
0.25
1.25 0.2 or 20%;
SUFFICIENT.
(2) is indicates that D = B −60, but B is
unknown. For example, B could be 100
and the value of −BD
B would be 60
100, or B
could be 500 and the value of −BD
B would
be 60
500; NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
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309
6.5 Data Suffi ciency Answer Explanations
287. Jack wants to use a circular rug on his rectangular
of ce oor to cover two small circular stains, each
less than
π
100 square feet in area and each more than
3 feet from the nearest wall. Can the rug be placed to
cover both stains?
(1) Jack’s rug covers an area of 9π square feet.
(2) The centers of the stains are less than 4 feet apart.
Geometry Applied problems; Circles
If a circle with radiusr has area less than 100
π
,
then πr2< 100
π
, or r2< 1
100 . Hence, r< 1
10 , so
the circle’s radius is less than 1
10 ft.
(1) Given that the circular rug has area 9πft2,
the radius of the rug, Rft, satis es the
equation πR2=9π, and so R2=9, or R=3.
If the centers of the circular stains are 4ft
apart, then the midpoint of the centers will
be a distance of at most 1
10 21
10
++
⎛
⎝⎞
⎠
ft=2.2ft from any point on the stains.
us, if the circular rug (which has radius
3ft) were placed so that its center lies on
that midpoint, then the rug would cover
both stains. However, if the centers of the
circular stains are 7ft apart, then the circular
rug (which has diameter 6ft) cannot be
placed to cover both stains; NOT su cient.
(2) Given that the centers of the circular stains
are less than 4ft apart, it is not possible to
determine whether the circular rug can be
placed to cover both stains since nothing
is given about the size of the circular rug;
NOT su cient.
Taking (1) and (2) together, the centers of the
circular stains are less than 4ft apart and it
follows from the discussion in (1) that the circular
rug can be placed to cover both stains.
e correct answer is C;
both statements together are su cient.
a×
d
egh
hj
e
f
fa
b
b
c
c
288. In the multiplication table above, each letter represents
an integer. What is the value of c ?
(1) c = f
(2) h≠0
Arithmetic Properties of numbers
(1) Given that c=f, the examples below, in which
a=b=1, show that the value of c could be 1
and the value of c could be 2; NOT su cient.
×1 11
11 11
11 11
11 11
×112
1112
1112
2224
(2) Given that h≠0, the examples in (1) show
that the value of c could be 1 and the value
of c could be 2; NOT su cient.
Taking (1) and (2) together is of no more help
than either (1) or (2) taken separately because
the same examples used to show that (1) is not
su cient also show that (2) is not su cient.
e correct answer is E;
both statements together are still not su cient.
289. If n is an integer, is (0.1)
n greater than (10)
n ?
(1) n > –10
(2) n < 10
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Arithmetic Exponents
(0.1)
n = 1
10n will be greater than 10
n if 1 is greater
than 10
2 n
, and this will be the case if and only if
n < 0. Determine if n < 0.
(1) is indicates that n is greater than –10.
is includes nonnegative values of n as well
as negative values of n ; NOT su cient.
(2) is indicates that n is less than 10, but
this includes negative values of n as well as
nonnegative values of n ; NOT su cient.
Taking (1) and (2) together, n can have any
value between –10 and 10 and can therefore be
negative or nonnegative.
e correct answer is E;
both statements together are still not su cient.
290. For a basic monthly fee of F yen (¥ F ), Naoko’s rst
cell phone plan allowed him to use a maximum of
420minutes on calls during the month. Then, for
each of x additional minutes he used on calls, he was
charged ¥ M , making his total charge for the month ¥ T ,
where T = F + xM . What is the value of F ?
(1) Naoko used 450minutes on calls the rst month
and the total charge for the month was ¥13,755.
(2) Naoko used 400minutes on calls the second
month and the total charge for the month was
¥13,125.
Algebra Simultaneous equations
(1) Given that Naoko used 450minutes
and was charged ¥13,125, it follows
that F +(450−420) M =13,755, or
F +30 M =13,755. However, the value
of F cannot be determined. For example,
F =13,005 and M =25 is possible, and
F =13,035 and M =24 is possible; NOT
su cient.
(2) Given that Naoko used 400minutes
and was charged ¥13,125, it follows that
F =13,125, since Naoko did not use more
than 420minutes; SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
291. The weights of all dishes of type X are exactly the
same, and the weights of all dishes of type Y are
exactly the same. Is the weight of 1 dish of type X
less than the weight of 1 dish of type Y ?
(1) The total weight of 3 dishes of type X and
2dishes of type Y is less than the total weight of
2dishes of type X and 4 dishes of type Y.
(2) The total weight of 4 dishes of type X and
3dishes of type Y is less than the total weight of
3dishes of type X and 4 dishes of type Y.
Algebra Inequalities
Let x be the weight of a typeX dish and let y be the
weight of a typeY dish. Determine whether x < y .
(1) Given that 3 x + 2 y < 2 x + 4 y , or x < 2 y , it
is possible that x < y is true (for example, if
x = 2 and y =3) and it is possible that x < y is
false (for example, if x = 3 and y = 2); NOT
su cient.
(2) Given that 4 x + 3 y < 3 x + 4 y , it follows
that x < y ; SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
292. If r and t are three-digit positive integers, is r greater
than t ?
(1) The tens digit of r is greater than each of the
three digits of t.
(2) The tens digit of r is less than either of the other
two digits of r.
Arithmetic Properties of numbers
Let r3, r2, and r1 be the hundreds, tens, and units
digits, respectively, of the 3-digit integer r, and
let t3, t2, and t1 be the hundreds, tens, and units
digits, respectively, of the 3-digit integer t.
(1) Given that r2 is greater than each of t3, t2,
and t1, then r could be greater than t (for
example, if r=242 and t=222) and r could
be less than t (for example, if r=242 and
t=333); NOT su cient.
(2) Given that r2 is less than either of r1 or r3,
then r could be greater than t (for example,
if r=212 and t=111) and r could be less
than t (for example, if r=212 and t=222);
NOT su cient.
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6.5 Data Suffi ciency Answer Explanations
Taking (1) and (2) together, r3>r2 follows from
(2) and r2>t3 follows from (1). erefore, r3>t3
and hence r is greater than t.
e correct answer is C;
both statements together are su cient.
293. Is the product of two positive integers x and y divisible
by the sum of x and y ?
(1) x=y
(2) x=2
Arithmetic Properties of numbers
(1) Given that x=y, then xy could be divisible
by x+y (for example, if x=y=2, then
xy=4 is divisible by x+y=4) and xy could
fail to be divisible by x+y (for example,
if x=y=3, then xy=9 is not divisible by
x+y=6); NOT su cient.
(2) Given that x=2, then xy could be divisible
by x+y (for example, if x=y=2, then
xy=4 is divisible by x+y=4) and xy could
fail to be divisible by x+y (for example, if
x=2 and y=3, then xy=6 is not divisible
by x+y=5); NOT su cient.
Taking (1) and (2) together, it follows that
x=y=2, and so xy=4 is divisible by x+y=4.
e correct answer is C;
both statements together are su cient.
294. A certain high school with a total enrollment of
900students held a science fair for three days
last week. How many of the students enrolled in the high
school attended the science fair on all three days?
(1) Of the students enrolled in the school, 30 percent
attended the science fair on two or more days.
(2) Of the students enrolled in the school, 10 percent
of those that attended the science fair on at
least one day attended on all three days.
Algebra Simultaneous equations
Let a , b , and c be the numbers of students who
attended on exactly one day, exactly two days, and
exactly three days, respectively, and let n be the
number of students who did not attend on any
of the three days. Given that a + b + c + n = 900,
determine the value of c .
(1) Given that (30%)(900) = b + c , or b + c = 270,
more than one positive integer value for c is
possible; NOT su cient.
(2) Given that (10%)( a + b + c ) = c , or
a + b + c = 10 c , or a + b = 9 c , more than
one positive integer value for c is possible;
NOT su cient.
(1) and (2) together are not su cient because
more than one positive integer value for c is
possible. Although there are 4 variables and only
3 linear equations involving these 4 variables,
which implies there exist in nitely many real
number solutions, the variables in the present
problem are further restricted to be positive
integers . However, speci c values of c can be
obtained using the equations:
I. a + b + c + n = 900 (from the information in
the question)
II. b + c = 270 (from statement (1))
III. a + b = 9 c (from statement (2))
IV. 10 c + n = 900 (from combining I and III)
For example, if n = 600, then c = 30 from IV,
b = 240 from II, and a = 30 from III. On the
other hand, if n= 500, then c = 40 from IV,
b = 230 from II, and a= 130 from III.
e correct answer is E;
both statements together are still not su cient.
295. The average (arithmetic mean) price of the 3 items that
Kate purchased from a clothing store was $50. If there
was no sales tax on any item that had a price of less
than $80 and 6 percent sales tax on all other items,
what was the total sales tax on the 3 items that Kate
purchased?
(1) The price of the most expensive item that Kate
purchased from the store was $100.
(2) The price of the least expensive item that Kate
purchased from the store was $10.
Arithmetic Applied problems; Percents
Kate purchased 3items, the average price of which
was $50, and paid 6% sales tax on each item priced
over $80. Determine the total tax that Kate paid.
Given that the average of the 3 prices is
$50, it follows that the sum of the 3 prices is
(3)($50) = $150.
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(1) One of the prices is $100. erefore,
the sum of the 2 remaining prices is
$150−$100 = $50. Hence, each of the
remaining items has a price that is less
than $80 and thus is not taxed. It follows
that the total sales tax on the 3 items is the
sales tax on the $100 item, which equals
(6%)($100) = $6; SUFFICIENT.
(2) One of the prices is $10. erefore,
the sum of the 2 remaining prices is
$150−$10 = $140. If the 2remaining
prices are $70 and $70, then none of the
items has a price greater than $80, and
hence the total sales tax on the 3 items is $0.
If the 2 remaining prices are $40 and $100,
then the total sales tax on the 3 items is
(6%)($100) = $6; NOT su cient.
is solution assumes tax is not included in the
quoted prices. If tax were included in the quoted
prices, then some minor adjustments in the
numerical examples would be needed. However,
the su ciency of (1) and insu ciency of (2)
would not be a ected.
e correct answer is A;
statement 1 alone is su cient.
296. A company makes and sells two products, P and Q.
The costs per unit of making and selling P and Q are
$8.00 and $9.50, respectively, and the selling
prices per unit of P and Q are $10.00 and $13.00,
respectively. In one month the company sold a total
of 834 units of these products. Was the total pro t on
these items more than $2,000.00 ?
(1) During the month, more units of P than units of
Q were sold.
(2) During the month, at least 100 units of Q were sold.
Arithmetic Applied problems
It is given that the pro t on each unit of P
is $10.00−$8.00=$2.00, and the pro t on
each unit of Q is $13.00−$9.50=$3.50. Also
if p and q represent the number of units of
Products P and Q made and sold, then it is given
that p + q =834. Determining if the total pro t
on these items was more than $2,000 requires
determining how many units of at least one of the
products were sold.
(1) is indicates that p > q , but does not give
a speci c value for p or q ; NOT su cient.
(2) is indicates that q ≥ 100, but does not
give a speci c value for q ; NOT su cient.
Taking (1) and (2) together, p > q and q ≥ 100,
so p> 100, but a speci c value for p or q cannot
be determined.
e correct answer is E;
both statements together are still not su cient.
297. Jill has applied for a job with each of two different
companies. What is the probability that she will get job
offers from both companies?
(1) The probability that she will get a job offer from
neither company is 0.3.
(2) The probability that she will get a job offer from
exactly one of the two companies is 0.5.
Arithmetic Probability
Let P (2) be the probability that she will get
a job o er from both companies, P (1) be the
probability that she will get a job o er from
exactly one of the companies, and P (0) be the
probability that she will get a job o er from
neither company. en P (2)+ P (1)+ P (0)=1.
What is the value of P (2)?
(1) Given that P (0)=0.3, it follows that
P (2)+ P (1)+0.3=1, or P (2)+ P (1)=0.7.
However, the value of P (2) cannot be
determined, since nothing is known about
the value of P (1) other than 0≤ P (1)≤0.7;
NOT su cient.
(2) (2) Given that P (1)=0.5, it follows that
P (2)+0.5+ P (0)=1, or P (2)+ P (0)=0.5.
However, the value of P (2) cannot be
determined, since nothing is known about
the value of P (0) other than 0≤ P (1)≤0.5;
NOT su cient.
Taking (1) and (2) together, it follows that
P (2)+0.5+0.3=1, or P (2)=0.2.
e correct answer is C;
both statements together are su cient.
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6.5 Data Suffi ciency Answer Explanations
298. A scientist recorded the number of eggs in each of
10birds’ nests. What was the standard deviation of the
numbers of eggs in the 10 nests?
(1) The average (arithmetic mean) number of eggs
for the 10 nests was 4.
(2) Each of the 10 nests contained the same
number of eggs.
Arithmetic Statistics
Note that if all of the values of a data set are equal
to the same number, say x , the di erence between
each data value and the average is x − x =0, the
sum of the squares of these di erences is 0, and so
the standard deviation is 0. On the other hand, if
the values in a data set are not all equal, then the
standard deviation will be positive.
(1) If each of the 10 nests had 4 eggs, then
the average would be 4 and the standard
deviation would be 0. If 8nests had 4eggs,
1 nest had 3 eggs, and 1 nest had 5eggs,
then the average would be 4 and the
standard deviation would be positive;
NOT su cient.
(2) Since all of the data values are equal to the
same number, the standard deviation is 0;
SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
299. A conveyor belt moves bottles at a constant speed of
120centimeters per second. If the conveyor belt moves
a bottle from a loading dock to an unloading dock, is
the distance that the conveyor belt moves the bottle
less than 90 meters? (1 meter = 100 centimeters)
(1) It takes the conveyor belt less than 1.2 minutes
to move the bottle from the loading dock to the
unloading dock.
(2) It takes the conveyor belt more than 1.1 minutes
to move the bottle from the loading dock to the
unloading dock.
Arithmetic Applied problems
Since the rate at which the conveyor belt moves
is given as 120 centimeters per second, which
is equivalent to =
120
100 1.2 meters per second,
the conveyor will move less than 90 meters if it
moves for less than 90
1.2 75= seconds.
(1) is indicates that the length of time the
conveyor belt moves is less than 1.2 minutes,
which is equivalent to (1.2)(60) = 72
seconds and 72 < 75; SUFFICIENT.
(2) is indicates that the length of time
the conveyor belt moves is more than
1.1 minutes, which is equivalent to
(1.1)(60) = 66 seconds, but does not indicate
how much more than 66 seconds the
conveyor moves. If the conveyor moves for
70 seconds (70 > 66), for example, it moves
less than 90 meters since 70 < 75. However,
if the conveyor belt moves for 80 seconds
(80 > 66), then it moves more than
90 meters since 80 > 75; NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
300. If x, y, and z are positive numbers, what is the value of
the average (arithmetic mean) of x and z ?
(1) x−y = y−z
(2) x2−y2 = z
Algebra Statistics; Simplifying algebraic
expressions
(1) Given that x−y=y−z, it follows that
x+z=2y, or y= xz
2
+. erefore, y is
the average of x and z. However, it is not
possible to determine the value of y. For
example, x=y=z=3 gives three positive
numbers that satisfy x−y=y−z,
and x=y=z=4 gives three positive
numbers that satisfy x−y=y−z;
NOT su cient.
(2) Given that x2−y2=z, it is not possible to
determine the value of xz
2
+, the average
of the x and z. For example, if x=3,
y=2, and z=5, then x2−y2=z is true
(because 32−22=9−4=5) and xz
2
+=
35
2
+=4. However, if x=5, y=4, and
z=9, then x2−y2=z is true (because
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52−42=25−16=9) and xz
2
+=
59
2
+=7; NOT su cient.
Taking (1) and (2) together, it follows
that x+z=2y and x2−y2=z, so
x+(x2−y2)=2y, or x+x2=y2+2y. Adding
1 to both sides of this last equation gives
x+x2+1=y2+2y+1=(y+1)2, which
simpli es the task of nding positive numbers
x, y, and z that satisfy both (1) and (2) and for
which the values of xz
2
+=y can be di erent.
For one example, letting x=1 gives x+x2+1=3,
and thus (y+1)2=3. Solving for a positive value
of y gives y+1= 3, or y= 3−1, and by
using x+z=2y, the corresponding value of z is
2y−x=2( 3−1)−1=23−3. Note that
23−3 is positive because (2 3)2=4(3)=12
is greater than 32=9. e values x=1, y=
3−1, and z=23−3 satisfy both (1) and
(2), and for this choice of values of x, y, and z,
the value of xz
2
+=y is 3−1. For another
example, letting x=2 gives x+x2+1=7, and
thus (y+1)2=7. Solving for a positive value
of y gives y+1= 7, or y= 7−1, and by
using x+z=2y, the corresponding value of z is
2y−x=2( 7−1)−2=27−4. Note that
27−4 is positive because (2 7)2=4(7)=28
is greater than 42=16. e values x=2, y=
7−1, and z=27−4 satisfy both (1) and
(2), and for this choice of values of x, y, and z, the
value of xz
2
+=y is 7−1; NOT su cient.
e correct answer is E;
both statements together are still not su cient.
301. The rectangular rug shown in the gure above has an
accent border. What is the area of the portion of the
rug that excludes the border?
(1) The perimeter of the rug is 44 feet.
(2) The width of the border on all sides is 1 foot.
Geometry Rectangles; Perimeter
(1) Given that the perimeter of the rug is 44 ft,
then the rectangular rug could have area
121 ft
2 (length = 11ft and width = 11 ft)
and the rectangular rug could have area
96 ft
2 (length = 16 ft and width = 6 ft).
Moreover, no information is given about
the width of the accent border, so even if
the area of the rectangular rug could be
determined, it would still not be possible to
determine the area of the portion of the rug
that excludes the border; NOT su cient.
(2) Given that the width of the border is 1 ft, the
area of the portion of the rug that excludes the
border is ( L −2)( W −2) ft
2 , where L ft and
W ft are the length and width, respectively, of
the rug. If L = W = 11, then ( L −2)( W −2) = 81.
However, if L = 16 and W = 6, then
( L −2)( W −2) = 56; NOT su cient.
Taking (1) and (2) together, the area could be
81ft
2 or 56ft
2 as shown by the examples in
(1) and (2).
e correct answer is E;
both statements together are still not su cient.
302. Terry holds 12 cards, each of which is red, white,
green, or blue. If a person is to select a card randomly
from the cards Terry is holding, is the probability less
than 1
2 that the card selected will be either red or
white?
(1) The probability that the person will select a blue
card is 1
3.
(2) The probability that the person will select a red
card is 1
6.
Arithmetic Probability
Determine if the probability is less than 1
2 that a
card selected at random from 12 cards, each of
which is red, white, green, or blue, will be either
red or white. at is, determine whether the
number of cards that are red or white is less than
1
2 (12) = 6.
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6.5 Data Suffi ciency Answer Explanations
(1) It is given that the probability is 1
3 that the
selected card will be blue. is means that
1
3(12) = 4 of the cards are blue. However,
there is no information about how many of
the 8 remaining cards are red, how many
are white, or how many are green. If, for
example, there are 2red cards, 2 white cards,
and 4 green cards, then the number of cards
that are red or white is 2 + 2 = 4, which is
less than 6. On the other hand, if there are
3 red cards, 4white cards, and 1 green card,
then the number of cards that are red or
white is 3 + 4 = 7, which is not less than 6;
NOT su cient.
(2) It is given that the probability is 1
6 that the
selected card will be red. is means that
1
6(12) = 2 of the cards are red. However,
there is no information about how many
of the 10 remaining cards are white, how
many are blue, or how many are green. If,
for example, there are 3 white cards, 5 blue
cards, and 2 green cards, then the number
of cards that are red or white is 2 + 3 = 5,
which is less than 6. On the other hand,
if there are 7white cards, 1 blue card, and
2 green cards, then the number of cards that
are red or white is 2 + 7 = 9, which is not
less than 6; NOT su cient.
Taking (1) and (2) together, there are 4blue cards
and 2red cards. However, there is no information
about how many of the 6 remaining cards are
white or how many are green. If, for example,
there are 3white cards and 3green cards, then
the number of cards that are red or white is
2+3=5, which is less than 6. On the other
hand, if there are 5white cards and 1green card,
then the number of cards that are red or white is
2+5=7, which is not less than 6.
e correct answer is E;
both statements together are still not su cient.
303. If y ≠2 xz , what is the value of +
−
xz yz
xz y
2
2 ?
(1) 2 x + y = 3
(2) z = 2
Algebra Simplifying algebraic expressions
e task is to determine the value of
+
−
xz yz
xz y
2
2= +
−
zx y
xz y
(2 )
2.
(1) is indicates 2 x + y =3, and so +
−
xz yz
xz y
2
2=
−
z
xz y
3
2. However, this is not enough
to determine the value of +
−
xz yz
xz y
2
2. For
example, if x =1, y =1, and z =2, then
2 x + y =3 and +
−
xz yz
xz y
2
2=2, but if x =0,
y =3, and z =2, then 2 x + y =3 and
+
−
xz yz
xz y
2
2= –2; NOT su cient.
(2) is indicates that z =2, and so +
−
xz yz
xz y
2
2=
+
−
xy
xy
42
4. However, this is not enough
to determine the value of +
−
xz yz
xz y
2
2. For
example, if x =1, y =1, and z =2, then
+
−
xz yz
xz y
2
2=2, but if x =0, y =3, and z =2,
then +
−
xz yz
xz y
2
2=–2; NOT su cient.
Taking (1) and (2) together is not enough to
determine the value of +
−
xz yz
xz y
2
2 because the
same examples used to show that (1) is not
su cient were also used to show that (2) is not
su cient.
e correct answer is E;
both statements together are still not su cient.
y°
z°
x°
304. In the parallelogram shown, what is the value of x ?
(1) y = 2 x
(2) x + z = 120
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Geometry Angles
(1) Given that y = 2 x and the fact that adjacent
angles of a parallelogram are supplementary,
it follows that 180= x + y = x + 2 x = 3 x , or
180 = 3 x . Solving this equation gives x = 60;
SUFFICIENT.
(2) Given that x + z = 120 and the fact
that opposite angles of a parallelogram
have the same measure, it follows that
120 = x + z = x + x , or 120 = 2 x . Solving
this equation gives x = 60; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
305. In a product test of a common cold remedy, x percent
of the patients tested experienced side effects from
the use of the drug and y percent experienced relief
of cold symptoms. What percent of the patients tested
experienced both side effects and relief of cold
symptoms?
(1) Of the 1,000patients tested, 15percent
experienced neither side effects nor relief of
cold symptoms.
(2) Of the patients tested, 30percent experienced
relief of cold symptoms without side effects.
Algebra Sets
One way to solve problems about sets is by using
a contingency table. For the information given
in this problem with T representing the total
number of people tested, the table might be as
follows:
side e ects no side e ects totals
relief of
symptoms ⎛
⎝
⎜⎞
⎠
⎟
yT
100
no relief of
symptoms
totals ⎛
⎝⎞
⎠
xT
100 T
(1) Using the information in (1) gives the
following table, where 15% of 1,000 is 150.
side e ects
no side
e ects totals
relief of
symptoms
⎛
⎝
⎜⎞
⎠
⎟
y
100 (1,000)
no relief of
symptoms
150
totals
⎛
⎝⎞
⎠
x
100 (1,000)
1,000
If x =55 and y =55, then the table becomes
side e ects no side e ects totals
relief of
symptoms 250 300 550
no relief of
symptoms 300 150 450
totals 550 450 1,000
and this gives 250
1,000 =25% as the percent
of patients tested who experienced both side
e ects and relief of cold symptoms.
However, if x =55 and y =50, then the table
becomes
side e ects no side e ects totals
relief of
symptoms 200 300 500
no relief of
symptoms 350 150 500
totals 550 450 1,000
and this gives 200
1,000 =20% as the percent
of patients tested who experienced both side
e ects and relief of cold symptoms;
NOT su cient.
(2) is indicates that 30% of the patients
tested experienced relief of cold symptoms
without side e ects. e same examples that
were used for (1) can be used here, also, to
show that di erent values can be obtained
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6.5 Data Suffi ciency Answer Explanations
for the percent of patients tested who
experienced both side e ects and relief of
cold symptoms; NOT su cient.
Since the examples satisfy both (1) and (2), these
statements taken together are not su cient to
determine the percent of patients tested who
experienced both side e ects and relief of cold
symptoms.
e correct answer is E;
both statements together are still not su cient.
306. Is x < 5 ?
(1) x2 > 5
(2) x2 + x < 5
Algebra Inequalities
(1) Given that x2>5, then x<5 can be true
(for example, if x=–3) and x<5 can be
false (for example, if x=6); NOT su cient.
(2) Given that x2+x<5, then x<5−x2. Also,
since x2≥0 is true for any real number x,
it follows that –x2≤0, or after adding 5
to both sides, 5−x2≤5. From x<5−x2
and 5−x2≤5, it follows that x<5;
SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
307. Is 4
x + y
= 8
10 ?
(1) x − y = 9
(2)
=
y
x
1
4
Algebra Properties of numbers
e question is equivalent to determining
whether (2
2 )
x + y
= (2
3 )
10 , which in turn is
equivalent to determining whether 2
2( x
+ y ) = 2
30 ,
which in turn is equivalent to determining
whether 2( x + y ) = 30, or x + y = 15.
(1) Given that x − y = 9, it is possible that
x + y = 15 (for example, x = 12 and y = 3)
and it is possible that x + y ≠15 (for example,
x = 10 and y = 1); NOT su cient.
(2) Given that =
y
x
1
4, or x = 4 y , it is possible
that x + y =15 (for example, x = 12 and
y = 3) and it is possible that x + y ≠ 15 (for
example, x = 4 and y = 1); NOT su cient.
Given (1) and (2) together, x − y = 9 and
x = 4 y , it follows that 4 y − y = 9, or y = 3, and
x = 4 y = 4(3) = 12. erefore, x + y = 12 + 3 = 15.
e correct answer is C;
both statements together are su cient.
308. Is zp negative?
(1) pz
4 < 0
(2) p + z
4 = 14
Arithmetic Properties of numbers
(1) Given that pz
4 < 0, zp can be negative
(choose p = –2 and z = 2) and zp can be
nonnegative (choose p = –2 and z = –2);
NOT su cient.
(2) Given that p + z
4 = 14, the same examples
used to show that (1) is not su cient can be
used for (2); NOT su cient.
Taking (1) and (2) together is of no more help
than either (1) or (2) taken separately because
the same examples used to show that (1) is not
su cient also show that (2) is not su cient.
e correct answer is E;
both statements together are still not su cient.
309. In each game of a certain tournament, a contestant
either loses 3 points or gains 2 points. If Pat had
100 points at the beginning of the tournament, how
many games did Pat play in the tournament?
(1) At the end of the tournament, Pat had 104 points.
(2) Pat played fewer than 10 games.
Arithmetic Computation with integers
Pat either lost 3points or gained 2points in
each game she played. erefore, since she had
100 points at the beginning of the tournament,
her score at the end of the tournament was
100−3 x +2 y , where x and y represent,
respectively, the number of games in which she
lost 3points and the number of games in which
she gained 2points. Determine the value of x + y .
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(1) is indicates that 100−3 x +2 y =104, but
no information is given about the values of x
or y . For example, the values of x and y could
be 0 and 2, respectively, so that x + y =2
or the values of x and y could be 2 and 5,
respectively, so that x + y =7; NOT su cient.
(2) is indicates that Pat played fewer than
10 games, but in each of the examples
above, Pat played fewer than 10 games;
NOT su cient.
Since the examples given satisfy both (1) and (2),
taking (1) and (2) together does not give enough
information to determine the value of x + y .
e correct answer is E;
both statements together are still not su cient.
310. At the beginning of the year, the Finance Committee
and the Planning Committee of a certain company
each had n members, and no one was a member of
both committees. At the end of the year, 5 members
left the Finance Committee and 3 members left the
Planning Committee. How many members did the
Finance Committee have at the beginning of the year?
(1) The ratio of the total number of members who
left at the end of the year to the total number of
members at the beginning of the year was 1:6.
(2) At the end of the year, 21 members remained on
the Planning Committee.
Algebra Applied problems
(1) It is given that =
n
8
2
1
6 , since a total of
3 + 5 = 8 members left at the end of the
year and there were a total of n + n =
2 n members at the beginning of the year.
It follows that (8)(6) = (2 n )(1), or n = 24;
SUFFICIENT.
(2) It is given that n −3 = 21, since 3 members
from the original n members left the
Planning Committee at the end of the
year. It follows that n = 21 + 3 = 24;
SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
311. Can a certain rectangular sheet of glass be positioned
on a rectangular tabletop so that it covers the entire
tabletop and its edges are parallel to the edges of the
tabletop?
(1) The tabletop is 36 inches wide by 60 inches long.
(2) The area of one side of the sheet of glass is
2,400square inches.
Geometry Area
Determine whether the length and width of the
sheet of glass are greater than or equal to the
length and width of the tabletop.
(1) e length and width of the tabletop are
given, but nothing can be determined about
the dimensions of the sheet of glass; NOT
su cient.
(2) e area of the sheet of glass is given,
but nothing can be determined about the
dimensions of the tabletop; NOT su cient.
(1) and (2) together are not su cient because the
information given does not specify the length and
width of the sheet of glass. For example, the length
and width of the sheet of glass could be 40 inches
and 60 inches and, since 40 ≥ 36 and 60 ≥ 60, the
answer to the question would be “Yes.” On the
other hand, the length and width of the sheet of
glass could be 100 inches and 24 inches, and in
this case the answer to the question would be “No”
because 24 is not greater than or equal to 36 or 60.
e correct answer is E;
both statements together are still not su cient.
312. In a random sample of 80 adults, how many are
college graduates?
(1) In the sample, the number of adults who are not
college graduates is 3 times the number who are
college graduates.
(2) In the sample, the number of adults who are not
college graduates is 40 more than the number
who are college graduates.
Algebra First-degree equations
Let C be the number of college graduates and let
N be the number who are not college graduates.
en, C+N= 80. Find the value of C .
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319
6.5 Data Suffi ciency Answer Explanations
(1) Since the number who are not college
graduates is 3 times the number who are,
N = 3 C . en C + 3 C = 80, 4 C = 80, and
C = 20; SUFFICIENT.
(2) Since the number who are not college
graduates is 40 more than the number who
are college graduates, N= C + 40. en
C + ( C + 40) = 80, 2 C + 40 = 80, 2 C= 40,
and C = 20; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
313. Max purchased a guitar for a total of $624, which
consisted of the price of the guitar and the sales tax.
Was the sales tax rate greater than 3 percent?
(1) The price of the guitar that Max purchased was
less than $602.
(2) The sales tax for the guitar that Max purchased
was less than $30.
Arithmetic Applied problems; Percents
Letting P be the price, in dollars, of the guitar
and r% be the sales tax rate, it is given that
Pr
1100
+
⎛
⎝⎞
⎠=624. Determine if r>3.
(1) Given that P<602, then 624=
Pr
1100
+
⎛
⎝⎞
⎠<602 r
1100
+
⎛
⎝⎞
⎠, and so
1+r
100 >624
602 . erefore, r
100 >
624
602 −1= 22
602 = 11
301 > 3
100 , because
(11)(100)>(3)(301), and so r>
100 3
100
⎛
⎝⎞
⎠=3; SUFFICIENT.
(2) Given that the sales tax was less than $30,
it is not possible to determine whether the
sales tax rate was greater than 3%. Since
(0.03)($624)=$18.72, a 3% sales tax rate
on the price corresponds to a sales tax that
is less than $18.72, since the price is less
than $624. erefore, it is possible that the
sales tax is less than $30 and the sales tax
rate is less than 3%, since any sales tax rate
less than 3% would give a sales tax that is
less than $18.72 (and hence less than $30).
However, it is also possible that the sales
tax is less than $30 and the sales tax rate is
4% (which is greater than 3%), since a 4%
sales tax rate implies P14
100
+
⎛
⎝⎞
⎠=624, or
P= 62,400
104 =600, and thus the sales tax
would be 0.04($600)=$24<$30; NOT
su cient.
e correct answer is A;
statement 1 alone is su cient.
314. What is the sum of a certain pair of consecutive odd
integers?
(1) At least one of the integers is negative.
(2) At least one of the integers is positive.
Arithmetic Properties of numbers
(1) Given that at least one of the integers
is negative, the sum could be –4 (if the
integers were –3 and –1) and the sum could
be 0 (if the integers were –1 and 1); NOT
su cient.
(2) Given that at least one of the integers is
positive, the sum could be 0 (if the integers
were –1 and 1) and the sum could be 4
(if the integers were 1 and 3); NOT
su cient.
Taking (1) and (2) together, the smaller of the
two numbers cannot be less than –1 (otherwise
(2) would not be true) and the larger of the two
numbers cannot be greater than 1 (otherwise (1)
would not be true). erefore, the integers must
be –1 and 1, and the sum must be 0.
e correct answer is C;
both statements together are su cient.
315. If a < x < b and c < y < d , is x < y ?
(1) a < c
(2) b < c
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320
Algebra Inequalities
Given a < x < b and c < y < d , determine if x < y .
(1) Even though a < c , there is no information
on the relative size of x and c . For example,
if a = 3, x = 10, b= 12, c = 4, y = 6, and d = 7,
a < c because 3 < 4 and x> y , since 10 > 6.
If, on the other hand, a = 3, x = 4, b =12,
c = 4, y = 6, and d = 7, a < c , because 3 < 4 and
x < y , since 4 < 6; NOT su cient.
(2) If b < c , then a < x < b < c < y < d and so
x < y ; SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
316. How many people are directors of both Company K
and Company R ?
(1) There were 17 directors present at a joint
meeting of the directors of Company K and
Company R, and no directors were absent.
(2) Company K has 12 directors and Company R
has 8 directors.
Algebra Sets
(1) is clarifies that Company K and
Company R together have 17 individuals
serving as directors. However, there is no
information as to the distribution of the
Company K directors, the Company R
directors, and the joint directors; NOT
sufficient.
(2) is gives the number of directors in each
company but no information as to the
number of joint directors; NOT sufficient.
Taking (1) and (2) together, it is known from (2)
that there are 20 directorships in all. If at a joint
meeting, there are only 17 people present, then
20 − 17 = 3 people must be joint directors.
e correct answer is C;
both statements together are sufficient.
317. The sum of 4 different odd integers is 64. What is the
value of the greatest of these integers?
(1) The integers are consecutive odd numbers.
(2) Of these integers, the greatest is 6 more than
the least.
Arithmetic Properties of numbers
Determine the greatest of four odd integers
whose sum is 64.
(1) is indicates that the integers are
consecutive odd integers. Letting z represent
the greatest of the four integers, it follows
that ( z −6)+( z −4)+( z −2)+ z =64,
from which a unique value of z can be
determined; SUFFICIENT.
(2) Letting w , x , y , and z represent four
di erent odd integers, where w < x < y < z ,
this indicates that z − w =6 or w = z −6.
is means that x = z −4 and y = z −2 since
w , x , y , and z must be di erent odd integers
and it must be true that w < x < y < z .
From w + x + y + z =64, it follows
that ( z −6)+( z −4)+( z −2)+ z =64
from which a unique value of z can be
determined; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
318. Was the number of books sold at Bookstore X last
week greater than the number of books sold at
Bookstore Y last week?
(1) Last week, more than 1,000 books were sold
at Bookstore X on Saturday and fewer than
1,000books were sold at Bookstore Y on
Saturday.
(2) Last week, less than 20 percent of the books
sold at Bookstore X were sold on Saturday
and more than 20 percent of the books sold at
Bookstore Y were sold on Saturday.
Arithmetic Inequalities
Determine if BookstoreX sold more books last
week than BookstoreY.
(1) is indicates that BookstoreX sold more
books on Saturday than BookstoreY, but
it gives no information about the numbers
of books sold by the two bookstores on the
other days of last week; NOT su cient.
(2) is gives information about the percents
of the books sold last week that were sold
on Saturday, but it gives no information
about the actual numbers of books sold at
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321
6.5 Data Suffi ciency Answer Explanations
the two bookstores last week. erefore, a
comparison of the numbers of books sold
last week by BookstoreX and BookstoreY
is not possible; NOT su cient.
Taking (1) and (2) together, if x represents the
number of books that BookstoreX sold on
Saturday and T
X represents the total number
of books that BookstoreX sold last week,
then x >1,000 and x <0.2 T
X . It follows that
1,000<0.2 T
X and so T
X >5,000. Similarly, if
y represents the number of books that BookstoreY
sold on Saturday and T
Y represents the total
number of books that BookstoreY sold last week,
then y <1,000 and y >0.2 T
Y . It follows that
0.2 T
Y <1,000, and so T
Y <5,000. Combining
the inequalities gives T
Y <5,000< T
X , and so
T
Y < T
X , which means that BookstoreX sold
more books last week than BookstoreY.
e correct answer is C;
both statements together are su cient.
319. From May 1 to May 30 in the same year, the balance in
a checking account increased. What was the balance in
the checking account on May 30 ?
(1) If, during this period of time, the increase in
the balance in the checking account had been
12percent, then the balance in the account on
May 30 would have been $504.
(2) During this period of time, the increase in the
balance in the checking account was 8 percent.
Arithmetic Applied problems; Percents
(1) Given that the amount on May 30 would
have been $504 if the increase had been
12%, it follows that the amount on May 1
was $ 504
1.12 = $450. However, the balance on
May 30 cannot be determined because the
(actual) percent increase is not given. For
example, if the increase had been 10%, then
the balance on May 30 would have been
(1.1)($450) = $495, which is di erent from
$504; NOT su cient.
(2) Given that the increase was 8%, the amount
on May 30 could be $108 (if the amount on
May 1 was $100) and the amount on May 30
could be $216 (if the amount on May 1 was
$200); NOT su cient.
Taking (1) and (2) together, it follows that the
amount on May30 was ($450)(1.08)=$486.
e correct answer is C;
both statements together are su cient.
320. If x and y are positive, is x < 10 < y ?
(1) x < y and xy = 100
(2) x
2 < 100 < y
2
Algebra Inequalities
(1) Given that x < y , multiply both sides by
x , which is positive, to get x
2 < xy . en,
since xy = 100, it follows that x
2 < 100.
Similarly, multiply both sides of x < y by
y , which is positive, to get xy < y
2 . Again,
since xy = 100, it follows that 100 < y
2 .
Combining x
2 < 100 and 100 < y
2 gives
x
2 < 100 < y
2 , from which it follows that
x2< 100 <y2 and, therefore,
x < 10 < y , since x and y are both positive;
SUFFICIENT.
(2) Given that x
2 < 100 < y
2 , it follows
that x < 10 < y as shown in (1) above;
SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
321. A merchant discounted the sale price of a coat and the
sale price of a sweater. Which of the two articles of
clothing was discounted by the greater dollar amount?
(1) The percent discount on the coat was
2percentage points greater than the
percent discount on the sweater.
(2) Before the discounts, the sale price of the coat
was $10 less than the sale price of the sweater.
Arithmetic Applied problems; Percents
(1) Given that the discount on the coat was
2percentage points greater than the
discount on the sweater, the sweater could
have been discounted by the greater dollar
amount ($30 sweater with 10% discount is a
discount of $3; $20 coat with 12% discount
is a discount of $2.40) and the coat could
have been discounted by the greater dollar
amount ($110 sweater with 10% discount is a
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discount of $11; $100 coat with 12% discount
is a discount of $12); NOT su cient.
(2) Given that the coat’s sale price was
$10 less than the sweater’s sale price, the
same examples used to show that (1) is
not su cient can be used for (2); NOT
su cient.
Taking (1) and (2) together is of no more help
than either (1) or (2) taken separately because
the same examples used to show that (1) is not
su cient also show that (2) is not su cient.
e correct answer is E;
both statements together are still not su cient.
322. A taxi company charges f cents for the rst mile of
the taxi ride and m cents for each additional mile. How
much does the company charge for a 10‐mile taxi ride?
(1) The company charges $0.90 for a 2‐mile ride.
(2) The company charges $1.20 for a 4‐mile ride.
Arithmetic Applied problems
If a taxi company charges f cents for the rst mile
and m cents for each additional mile, determine
the charge for a 10‐mile taxi ride, which can be
expressed as f + 9 m
(1) Since the charge for a 2‐mile ride is $0.90,
f + m = 0.90, and so f + 9 m = 0.90 + 8 m ,
but the value of m is unknown; NOT
su cient.
(2) Since the charge for a 4‐mile ride is $1.20,
f + 3 m = 1.20, and so f + 9 m = 1.20 + 6 m , but
the value of m is unknown; NOT su cient.
Taking (1) and (2) together and subtracting the
equation in (1) from the equation in (2) gives
2 m = 0.30 from which m = 0.15. en from (1),
f + 0.15 = 0.90 and f = 0.75. erefore, the charge
for a 10‐mile taxi ride is $0.75 + 9($0.15) = $2.10.
Alternatively, the graphs of f + m = 0.90 and
f + 3m = 1.20 in the ( f , m ) coordinate plane are
lines that intersect at exactly one point, and
therefore values of f and m can be determined,
from which f + 9 m can then be determined.
e correct answer is C;
both statements together are su cient.
323. If the positive integer n is added to each of the
integers 69, 94, and 121, what is the value of n ?
(1) 69 + n and 94 + n are the squares of two
consecutive integers.
(2) 94 + n and 121 + n are the squares of two
consecutive integers.
Algebra Computation with integers
Determine the value of the positive integer n .
(1) is indicates that 69+ n and 94+ n
are the squares of two consecutive
integers. Letting x and ( x +1) represent
the consecutive integers, it follows that
( x +1)
2 − x
2 = x
2 +2 x +1− x
2 =2 x +1.
erefore, (94+ n )−(69+ n )=2 x +1
or 25=2 x +1, from which x =12. en
12
2 =69+ n and n =144−69=75 or
(12+1)
2 =94+ n and n =169−94=75;
SUFFICIENT.
(2) is indicates that 94+ n and 121+ n
are the squares of two consecutive
integers. Letting x and ( x +1) represent
the consecutive integers, it follows that
( x +1)
2 − x
2 = x
2 +2 x +1− x
2 =2 x +1.
erefore, (121+ n )−(94+ n )=2 x +1
or 27=2 x +1, from which x =13. en
13
2 =94+ n and n =169−94=75 or
(13+1)
2 =121+ n and n =196−121=75;
SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
324. Guy’s net income equals his gross income minus his
deductions. By what percent did Guy’s net income
change on January 1, 1989, when both his gross
income and his deductions increased?
(1) Guy’s gross income increased by 4 percent on
January 1, 1989.
(2) Guy’s deductions increased by 15 percent on
January 1, 1989.
Arithmetic Percents
Let g
b represent Guy’s gross income and d
b
Guy’s deductions before January 1, 1989. Let
g
a represent Guy’s gross income and d
a Guy’s
deductions after January 1, 1989. Determine by
what percent Guy’s net income (gross income
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323
6.5 Data Suffi ciency Answer Explanations
minus deductions) changed on January 1, 1989,
when both his gross income and his deductions
increased, or nd gd gd
gd
()()
aa bb
bb
−−−
− as a percent.
(1) Guy’s gross income increased by 4 percent
on January 1, 1989, so g
a =1.04 g
b . en,
gd gd
gd
gd gd
gd
()()(1.04)()
,
aa bb
bb
ba bb
bb
−−−
−=−−−
−
However, no information is given
about the values of g
b , d
a , or d
b , and so
−−−
−
gd gd
gd
()()
aa bb
bb
cannot be determined;
NOT su cient.
(2) Guy’s deductions increased by 15 percent
onJanuary 1, 1989, so =dd1.15
ab
.
en, gd gd
gd
()()
aa bb
bb
−−−
−=
gdgd
gd
(1.15)( )
abbb
bb
−−−
−. However, no
information is given about the values of g
a ,
g
b , or d
b , and so −−−
−
gd gd
gd
()()
aa bb
bb
cannot be determined; NOT su cient.
Taking (1) and (2) together gives
−−−
−=−
−
gdgd
gd
gd
gd
(1.04 1.15 ) ( ) 0.04 0.15
bbbb
bb
bb
bb
,
which cannot be determined since the values of
g
b and d
b are unknown.
e correct answer is E;
both statements together are still not su cient.
325. If the ratio of the number of teachers to the number of
students is the same in School District M and School
District P, what is the ratio of the number of students in
School District M to the number of students in School
District P ?
(1) There are 10,000 more students in School
District M than there are in School District P.
(2) The ratio of the number of teachers to the number
of students in School District M is 1 to 20.
Algebra Ratios
Given that =
T
S
T
S
M
M
P
P
, where T
M and S
M are the
numbers of teachers and students, respectively,
in District M, and T
P and S
P are the numbers of
teachers and students, respectively, in District P,
nd the value of S
S
M
P
.
(1) Given that =+SS10, 000
MP , then
=+S
S
S
S
10, 000
M
P
P
P
, but the value of S
P is
unknown; NOT su cient.
(2) Given that =
T
S
1
20
M
M
and =
T
S
T
S
M
M
P
P
,
then =
T
S
1
20
P
P
. erefore, S
P = 20 T
P and
S
M = 20 T
M . It follows that =
S
S
T
T
20
20
M
P
M
P
,
but the values of T
M and T
P are unknown;
NOT su cient.
Taking (1) and (2) together, if S
P =1,000,
S
M = 1,000+10,000= 11,000, T
P =1,000
20 =50,
and ==T11,000
20 550
M, then =
S
S
11
1
M
P
. However,
if SS5,000, 5,000 10,000 15,000
PM
==+=
,
==T5,000
20 250
P, and ==T15,000
20 750
M, then
=
S
S
3
1
M
P
. erefore, the value of S
S
M
P
cannot be
determined.
e correct answer is E;
both statements together are still not su cient.
326. For a certain city’s library, the average cost of
purchasing each new book is $28. The library
receives $15,000 from the city each year; the library
also receives a bonus of $2,000 if the total number
of items checked out over the course of the year
exceeds 5,000. Did the library receive the bonus last
year?
(1) The library purchased an average of 50new
books each month last year and received enough
money from the city to cover this cost.
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324
(2) The lowest number of items checked out in one
month was 459.
Arithmetic Applied problems
(1) Given that the library purchased an average
of 50new books each month, for the entire
year the library purchased a total of (50)(12)=
600books for a total cost of (600)($28)=
$16,800. Excluding any possible bonus,
the library received $15,000 from the city.
Since this amount received from the city is
not enough to cover the cost of the books,
and the information provided in (1) says
that the total amount received from the city
was enough to cover the cost of the books,
it follows that the library received a bonus;
SUFFICIENT.
(2) Given that the least number of books
checked out in one month was 459, it follows
that the total number of books checked out
for the year was at least (12)(459) =5,508.
Since this is greater than 5,000, it follows
that the total number of books checked out
for the year was greater than 5,000 and the
library received a bonus; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
327. Each gift certi cate sold yesterday by a certain
bookstore cost either $10 or $50. If yesterday the
bookstore sold more than 5 gift certi cates that
cost $50 each, what was the total number of gift
certi cates sold yesterday by the bookstore?
(1) Yesterday the bookstore sold fewer than 10 gift
certi cates that cost $10 each.
(2) The total cost of gift certi cates sold yesterday
by the bookstore was $460.
Arithmetic Computation with integers
Let x be the number of $10 gift certi cates sold
yesterday and let y be the number of $50 gift
certi cates sold yesterday. It is given that y > 5.
Determine the value of x + y .
(1) It is given that x < 10, so x could be 0, 1, 2,
3, . . ., 9. Since y > 5, y could be 6, 7, 8, . . .,
and then x + y could be, for example,
0 + 6 = 6 or 2 + 8 = 10; NOT su cient.
(2) It is given that 10 x + 50 y = 460. Several
values of x and y with y > 5 will satisfy this
equation and give di erent values for x + y ,
as shown below; NOT su cient.
x y 10 x +50 y x + y
16 6 460 22
11 7 460 18
6 8 460 14
1 9 460 10
Taking (1) and (2) together, it can be seen from
the table that all the requirements are satis ed
by x = 6 and y = 8 and also by x = 1 and y = 9,
but the value of x + y is not uniquely determined;
NOT su cient.
e correct answer is E;
both statements together are still not su cient.
328. What is the tens digit of positive integer x ?
(1) x divided by 100 has a remainder of 30.
(2) x divided by 110 has a remainder of 30.
Arithmetic Properties of numbers
(1) Having a remainder of 30 when x is divided
by 100 can only happen if x has a tens digit
of 3 and a ones digit of 0, as in 130, 230,
630, and so forth; SUFFICIENT.
(2) When 140 is divided by 110, the quotient is
1 R30. However, 250 divided by 110 yields
a quotient of 2 R30, and 360 divided by
110 gives a quotient of 3 R30. Since there
is no consistency in the tens digit, more
information is needed; NOT sufficient.
e correct answer is A;
statement 1 alone is sufficient.
329. Three dice, each of which has its 6sides numbered
1 through 6, are tossed. The sum of the 3numbers that
are facing up is 12. Is at least 1 of these numbers 5?
(1) None of the 3numbers that are facing up is
divisible by 3.
(2) Of the numbers that are facing up, 2, but not all
3, are equal.
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325
6.5 Data Suffi ciency Answer Explanations
Arithmetic Properties of integers
When three dice, each with its 6faces numbered
1 through 6, are tossed and the sum of the three
integers facing up is 12, the possible outcomes are
{1, 5, 6}, {2, 4, 6}, {2, 5, 5}, {3, 3, 6}, {3, 4, 5}, and
{4, 4, 4}. Determine if, in the outcome described,
at least one of the numbers is 5.
(1) is indicates that none of the numbers
is divisible by three. e outcome could
be {4, 4, 4}. In this case, none of the three
numbers is 5. On the other hand, the
outcome could be {2, 5, 5}. In this case,
at least one of the numbers is 5;
NOT su cient.
(2) is indicates that two of the numbers,
but not all three, are equal. e outcome
could be {3, 3, 6}. In this case, none of the
three numbers is 5. On the other hand, the
outcome could be {2, 5, 5}. In this case,
at least one of the numbers is 5; NOT
su cient.
Taking (1) and (2) together, of the possible
outcomes {1, 5, 6}, {2, 4, 6}, {3, 3, 6}, and {3, 4, 5}
are eliminated because they do not satisfy (1), and
{4, 4, 4} is eliminated because it does not satisfy
(2). is leaves only {2, 5, 5}, and at least one
number is 5.
e correct answer is C;
both statements together are su cient.
330. On the number line, point R has coordinate r and point T
has coordinate t . Is t <0?
(1) –1 < r < 0
(2) The distance between R and T is equal to r
2 .
Arithmetic Number line
Determine if t , the coordinate of point T on the
number line, is negative.
(1) is indicates that r , the coordinate of
point R on the number line, lies between
–1 and 0, but gives no information about
the location of T in relation to either
point R or 0; NOT su cient.
(2) is indicates that the distance between
R and T , which can be expressed as | r − t |,
is r
2 . If r =2, for example, then |2− t |=4
so 2− t =4 or 2− t =–4. If 2− t =4, then
t =–2, which is negative. If 2− t =–4, then
t =6, which is not negative; NOT su cient.
Taking (1) and (2) together, if r − t ≥0,
then r − t = r
2 and t = r − r
2 = r (1− r ). Since
–1< r <0, it follows that 1<1− r <2, and
so t is the product of a negative number
( r ) and a positive number (1− r ) and is
therefore negative. Similarly, if r − t <0,
then | r − t |=–( r − t ) = t − r = r
2 and
t = r
2 + r = r ( r +1). Since –1< r <0, it follows
that 0< r +1<1, and so t is the product of a
negative number ( r ) and the positive number
( r +1) and is therefore negative.
e correct answer is C;
both statements together are su cient.
331. S is a set of points in the plane. How many distinct
triangles can be drawn that have three of the points in
S as vertices?
(1) The number of distinct points in S is 5.
(2) No three of the points in S are collinear.
Arithmetic Elementary combinatorics
(1) Given that the number of points in S is 5,
the number of triangles can be 0 (if the
points are collinear) and the number of
triangles can be greater than 0 (if the points
are not all collinear); NOT su cient.
(2) Given that no three points of S are collinear,
the number of triangles can be 1 (if S
consists of 3 points) and the number of
triangles can be 4 (if S consists of 4points);
NOT su cient.
Taking (1) and (2) together, the number of
distinct triangles must be 5
3
5!
3!(5 3)! 10
⎛
⎝⎞
⎠=−=,
which is the number of combinations of 5 points
taken 3 at a time.
e correct answer is C;
both statements together are su cient.
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332. Stores L and M each sell a certain product at a
different regular price. If both stores discount their
regular price of the product, is the discount price at
Store M less than the discount price at Store L ?
(1) At Store L the discount price is 10 percent
less than the regular price; at Store M the
discount price is 15 percent less than the regular
price.
(2) At Store L the discount price is $5 less than the
regular store price; at Store M the discount price
is $6 less than the regular price.
Arithmetic Percents
Let L
r and L
d be the regular and discounted
prices, respectively, at Store L, and let M
r and M
d
be the regular and discounted prices, respectively,
at Store M. Determine if M
d < L
d .
(1) Knowing that L
d = (1 − 0.10) L
r = 0.90 L
r
and that M
d = (1 − 0.15) M
r = 0.85 M
r gives
no information for comparing M
d and L
d ;
NOT su cient.
(2) Knowing that L
d = L
r –5 and that
Md = M
r −6 gives no information for
comparing M
d and L
d ; NOT su cient.
Taking (1) and (2) together gives 0.90 L
r = L
r − 5
and 0.85 M
r = M
r − 6, from which it follows that
0.10 L
r =5 or L
r = 50 and 0.15 M
r =6 or M
r =40.
en L
d = 50 − 5 = 45 and M
d = 40 − 6 = 34.
erefore, M
d < L
d .
e correct answer is C;
both statements together are su cient.
333. If d denotes a decimal, is d ≥ 0.5 ?
(1) When d is rounded to the nearest tenth, the
result is 0.5.
(2) When d is rounded to the nearest integer,
the result is 1.
Arithmetic Rounding; Estimating
(1) In this case, for example, the value of d
could range from the decimal 0.45 to 0.54.
Some of these, such as 0.51 or 0.52, are
greater than or equal to 0.5, and others,
such as 0.47 or 0.48, are less than 0.5;
NOT sufficient.
(2) When the result of rounding d to the
nearest integer is 1, d could range in value
from the decimal 0.50 to 1.49, which are
greater than or equal to 0.5; SUFFICIENT.
e correct answer is B;
statement 2 alone is sufficient.
334. In the two-digit integers 3■ and 2▲, the symbols ■ and
▲ represent different digits, and the product (3■)(2▲)
is equal to 864. What digit does ■ represent?
(1) The sum of ■ and ▲ is 10.
(2) The product of ■ and ▲ is 24.
Arithmetic Properties of numbers
(1) Given that ■+▲=10, then the possible
products ■▲ are (1)(9)= (9)(1)=9,
(2)(8)=(8)(2)=16, (3)(7)=(7)(3)=21,
(4)(6)=(6)(4)=24, and (5)(5)=25.Since
(3■)(2▲)=864 has units digit4, itfollows
that ■▲ must also have units digit4.Since
only two of the possible products of ■▲ has
units digit4, it follows that ■=4 and ▲=6,
or ■=6 and ▲=4. If ■=4 and ▲=6, then
(3■)(2▲)=(34)(26)=884≠864, and if
■=6 and ▲=4, then (3■)(2▲) =(36)(24)=
864. erefore,
■=6; SUFFICIENT.
(2) Given that
■▲=24, and that both ■ and ▲
are digits, there are four possibilities for the
values of ■ and ▲.
(a)
■=3 and ▲=8, which gives (3■)(2▲) =
(33)(28)=924≠864;
(b)
■=4 and ▲=6, which gives (3■)(2▲) =
(34)(26)=884≠864;
(c)
■=6 and ▲=4, which gives (3■)(2▲) =
(36)(24)=864;
(d)
■=8 and ▲=3, which gives (3■)(2▲) =
(38)(23)=874≠864.
erefore,
■=6; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
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327
6.5 Data Suffi ciency Answer Explanations
M
335. Two points, N and Q (not shown), lie to the right of
point M on line ℓ. What is the ratio of the length of QN
to the length of MQ ?
(1) Twice the length of MN is 3 times the length of MQ .
(2) Point Q is between points M and N .
Algebra Order
(1) Given that twice the length of MN is
3times the length of MQ , it follows that
the points are ordered from left to right as
M , Q , and N . us, letting MQ = x and
QN = y , it is given that 2( x + y ) = 3 x and
the value of y
x is to be determined. e given
equation can be rewritten as 2 x + 2 y = 3 x , or
2 y = x , or y
x
1
2
=; SUFFICIENT.
(2) Given that Q is between M and N , the ratio
of QN to MQ can be close to zero (if Q and
N are close together and both far from M )
and the ratio of QN to MQ can be large (if
M and Q are close together and both far
from N ); NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
336. Did the sum of the prices of three shirts exceed $60 ?
(1) The price of the most expensive of the shirts
exceeded $30.
(2) The price of the least expensive of the shirts
exceeded $20.
Arithmetic Applied problems
(1) Given that the price of the most expensive
shirt exceeded $30, the sum of the prices of
the shirts can be under $60 (if the prices were
$10, $10, and $35) and the sum of the prices
of the shirts can be over $60 (if the prices
were $10, $10, and $50); NOT su cient.
(2) Given that the price of the least expensive
shirt exceeded $20, it follows that the
sum of the prices of the shirts exceeds
3($20) = $60; SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
337. What is the total number of coins that Bert and
Claire have?
(1) Bert has 50 percent more coins than Claire.
(2) The total number of coins that Bert and Claire
have is between 21 and 28.
Arithmetic Computation with integers
Determine the total number of coins Bert and
Claire have. If B represents the number of coins
that Bert has and C represents the number of
coins that Claire has, determine B + C .
(1) Bert has 50% more coins than Claire, so
B = 1.5 C , and B + C = 1.5 C + C = 2.5 C , but
the value of C can vary; NOT su cient.
(2) e total number of coins Bert and
Claire have is between 21 and 28, so
21< B + C <28 and, therefore, B+C could
be 22, 23, 24, 25, 26, or 27; NOT su cient.
Taking (1) and (2) together, 21 < 2.5 C < 28 and
then C
21
2.5
28
2.5
<< or 8.4< C <11.2.
If C = 9, then B = (1.5)(9) = 13.5; if C = 10,
then B = (1.5)(10) = 15; and if C = 11, then
B = (1.5)(11) = 16.5. Since B represents a number
of coins, B is an integer. erefore, B = 15, C = 10,
and B + C = 25.
e correct answer is C;
both statements together are su cient.
338. A telephone station has x processors, each of which
can process a maximum of y calls at any particular
time, where x and y are positive integers. If 500 calls
are sent to the station at a particular time, can the
station process all of the calls?
(1) x = 600
(2) 100 < y < 200
Algebra Applied problems
At a particular time, the telephone station can
process a maximum of xy calls, where x and y are
positive integers. Determine whether xy ≥ 500.
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(1) Given that x = 600, it follows that
xy ≥ 600 since y ≥ 1 ( y is a positive
integer); SUFFICIENT.
(2) Given that 100 < y < 200, xy < 500 is
possible (if x = 3 and y = 150) and
xy ≥ 500 is possible (if x = 10 and y = 150);
NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
Price per Flower
Roses $1.00
Daisies $0.50
339. Kim and Sue each bought some roses and some
daisies at the prices shown above. If Kim bought the
same total number of roses and daisies as Sue, was
the price of Kim’s purchase of roses and daisies higher
than the price of Sue’s purchase of roses and daisies?
(1) Kim bought twice as many daisies as roses.
(2) Kim bought 4 more roses than Sue bought.
Algebra Applied problems
Let RK be the number of roses that Kim
bought, let RS be the number of roses that Sue
bought, and let T be the total number of roses
and daisies each bought. en Kim bought
(T−RK)daisies and Sue bought (T−RS)daisies.
For the roses and daisies, Kim paid a total of
$[RK+ 1
2(T−RK)]=$1
2(RK+T) and Sue paid
a total of $[RS+ 1
2(T−RS)]=$1
2(RS+T).
Determine whether 1
2(RK+T)> 1
2(RS+T), or
equivalently, determine whether RK>RS.
(1) Given that T−RK=2RK, or T=3RK, it is
not possible to determine whether RK>RS
because no information is provided about
the value of RS; NOT su cient.
(2) Given that RK=RS+4, it follows that
RK>RS; SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
340. Jazz and blues recordings accounted for 6 percent of
the $840 million revenue from the sales of recordings
in Country Y in 2000. What was the revenue from
the sales of jazz and blues recordings in Country Y in
1998 ?
(1) Jazz and blues recordings accounted for
5 percent of the revenue from the sales of
recordings in Country Y in 1998.
(2) The revenue from the sales of jazz and blues
recordings in Country Y increased by 40 percent
from 1998 to 2000.
Arithmetic Percents
It is given that jazz and blues recordings
accounted for 6% of the $840million revenue
of recordings in CountryYin 2000. Determine
the revenue from the sales of jazz and blues
recordings in 1998.
(1) is indicates that jazz and blues recordings
accounted for 5% of the revenue from
the sales of recordings in CountryYin
1998. However, no information is given
to indicate what the revenue from the
sales of recordings was in 1998. erefore,
the revenue from sales of jazz and blues
recordings in 1998 cannot be determined;
NOT su cient.
(2) is indicates that the revenue from
the sales of jazz and blues recordings
in CountryYincreased by 40% from
1998 to 2000. Letting R
1998 and R
2000
represent the revenue from the sales of
jazz and blues recordings in 1998 and
2000, respectively, then R
2000 =1.4 R
1998 ,
and so (0.06)($840million)=1.4 R
1998 ,
from which R
1998 can be determined;
SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
341. On a certain nonstop trip, Marta averaged x miles per
hour for 2 hours and y miles per hour for the remaining
3hours. What was her average speed, in miles
per hour, for the entire trip?
(1) 2 x + 3 y = 280
(2) y = x + 10
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329
6.5 Data Suffi ciency Answer Explanations
Algebra Rate problems
Marta traveled a total of (2 x + 3 y ) miles in
2 + 3 = 5hours for an average speed of +
⎛
⎝
⎜⎞
⎠
⎟
xy23
5
miles per hour. Determine the value of +xy23
5.
(1) Given that 2 x + 3 y = 280, it follows that
+xy23
5=280
5; SUFFICIENT.
(2) Given that y = x + 10, it follows that
+xy23
5= ++xx23(10)
5= x +6.
erefore, the value of +xy23
5 can be
56 (if x = 50 and y = 60) and the value of
+xy23
5 can be 61 (if x = 55 and y = 65);
NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
342. If x is a positive integer, what is the value of
+−xx24 ?
(1)
x is an integer.
(2) +x24 is an integer.
Arithmetic Operations with radicals
Determine the value of +x24− x.
(1) is indicates that x is a perfect square. If
x =1, then +x24− x= +124
− 1=
5−1=4. However, if x =25, then
+x24− x= +25 24− 25
=7−5=2;
NOT su cient.
(2) is indicates that +x24 is an integer. In
each of the examples above, +x24 is an
integer; NOT su cient.
Because the same examples were used to establish
that neither (1) nor (2) is su cient, it is not
possible to determine the value of +x24− x
from the given information.
e correct answer is E;
both statements together are still not su cient.
343. A tank is lled with gasoline to a depth of exactly
2 feet. The tank is a cylinder resting horizontally on
its side, with its circular ends oriented vertically. The
inside of the tank is exactly 6 feet long. What is the
volume of the gasoline in the tank?
(1) The inside of the tank is exactly 4 feet in diameter.
(2) The top surface of the gasoline forms a
rectangle that has an area of 24 square feet.
Geometry Cylinders; Volume
(1) Given that the diameter of the cylindrical
tank is 4ft, it follows that its radius is 2 ft.
erefore, the radius and height of the
cylindrical tank are known, and hence the
volume of the gasoline is half the volume of the
cylinder, or 1
2π r
2 h = 1
2π (2 ft)
2 (6 ft) = 12π ft
3 ;
SUFFICIENT.
A' B' C
'
C
O
2
2
x'
xr
r
A
P
B
(2) Given that the rectangular surface of the
gasoline forms a rectangle with area 24 ft
2
and length 6 ft, the width of the rectangular
surface is 4 ft. Let r ft be the radius of the
cylinder. e gure shows a vertical cross‐
section of the cylindrical tank—a circle
with center O —with the two possibilities
for the location of the top surface of the
gasoline: the depth of the gasoline is less
than or equal to r ft ( AC marks the location
of the top surface of the gasoline and
BP = 2 ft is the depth of the gasoline) or
the depth of the gasoline is greater than or
equal to r ft (AC′′
marks the location of
the top surface of the gasoline and B ′P = 2 ft
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is the depth of the gasoline). For the rst
possibility, Δ OBC is a right triangle with
hypotenuse
O
C of length r ft, so letting
OB = x ft, it follows from the Pythagorean
theorem that r
2 = x
2 + 2
2 = x
2 + 4.
However, because r = OB + BP = x + 2,
it follows that r
2 = ( x + 2)
2 = x
2 + 4 x + 4.
erefore, x
2 + 4 = x
2 + 4 x + 4, so 4 x = 0,
x = 0, and AC is a diameter of the circle.
us, the diameter of the cylindrical tank is
4 ft, and by the same reasoning used in (1),
the volume of the gasoline can be
determined. For the second possibility,
Δ OB ′C ′ is a right triangle with hypotenuse
OC′ of length r ft, so letting B ′O = x ′ ft, it
follows from the Pythagorean theorem that
r
2 = ( x ′ )
2 + 2
2 = ( x ′ )
2 + 4. However, because
r = B ′P − B ′O = 2− x ′ , it follows that
r
2 = (2− x ′ )
2 = 4−4 x ′ + ( x ′ )
2 . erefore,
( x ′ )
2 + 4 = 4−4 x ′ + ( x ′ )
2 , so 0 = –4 x ′ ,
x ′ = 0, and AC′′
is a diameter of the circle.
us, the diameter of the cylindrical tank
is 4 ft, and by the same reasoning used
in (1), the volume of the gasoline can be
determined; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
qrst
344. Of the four numbers represented on the number line
above, is r closest to zero?
(1) q =– s
(2) – t < q
Algebra Order
rqts
Referring to the gure above, in which it may be
assumed that q , r , s , and t are di erent numbers,
determine if r is closest to 0.
(1) Since q = – s , one of q and s is positive and
the other is negative. Since s is to the right
of q , then s is positive and q is negative.
Also, 0 is halfway between q and s , so q and
s are the same distance from 0. If r = 0, then,
of q , r , s , and t , r is closest to 0 because it IS 0.
If r ≠0 then either (i) q < 0 < r < s < t or
(ii) q < r < 0 < s < t .
rqts
0
(i) If q < 0 < r < s < t , as shown above, r is
closer to 0 than s is because r is between
0 and s , and r is clearly closer to 0 than
t is because t is farther away from
0 than s is. Also, since q and s are the
same distance from 0 and r is closer to
0 than s is, then r is closer to 0 than q is.
erefore, r is closest to 0.
0
rqts
(ii) If q < r < 0 < s < t , as shown above,
r is closer to 0 than q is because r is
between 0 and q . Also, r is closer to
0 than s is because r is closer to 0 than
q is and q and s are the same distance
from 0. Moreover, r is closer to 0 than
t is because t is farther away from
0 than s is. erefore, r is closest to 0.
In each case, r is closest to 0;
SUFFICIENT.
(2) If− t < q, then – t is to the left of q .
If t = 5, s =4, r = 3, and q =–2, then
–5 < –2, so (2) is satis ed. In this case,
q is closest to 0. On the other hand, if t = 5,
s = 4, r = –1, and q =−2, then –5 < –2, so
(2) is satis ed, but r is closest to 0; NOT
su cient.
e correct answer is A;
statement 1 alone is su cient.
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6.5 Data Suffi ciency Answer Explanations
345. A group consisting of several families visited an
amusement park where the regular admission fees
were ¥5,500 for each adult and ¥4,800 for each child.
Because there were at least 10people in the group,
each paid an admission fee that was 10% less than the
regular admission fee. How many children were in the
group?
(1) The total of the admission fees paid for the
adults in the group was ¥29,700.
(2) The total of the admission fees paid for the children
in the group was ¥4,860 more than the total of the
admission fees paid for the adults in the group.
Arithmetic Simultaneous equations
Determine the number of children in a group of
at least 10people who visited an amusement park.
(1) is indicates that (0.9)(5,500) A =29,700,
where A represents the number of adults in
the group. From this, the number of adults
can be determined. However, the number of
children in the group cannot be determined
without additional information about the
exact number of people in the group; NOT
su cient.
(2) If C and A represent the numbers
of children and adults, respectively,
in the group, this indicates that
(0.9)(4,800) C =(0.9)(5,500) A +4,860, or
48 C =55 A +54, or 48 C −55 A =54, which
is a single equation with two variables from
which unique values of C and A cannot be
determined, even under the assumptions
that C and A are integers such that
C + A ≥10. For example, the values of C
and A could be 8 and 6, respectively, since
(48)(8)−(55)(6)=54, or the values of C
and A could be 63 and 54, respectively, since
(48)(63)– (55)(54)=54; NOT su cient.
Taking (1) and (2) together, it follows that
A = 29,700
(0.9)(5,500)=6 and
C =(0.9)(5,500)(6) 4,860
(0.9)(4,800)
+=8.
e correct answer is C;
both statements together are su cient.
ADC
B
x°
346. What is the area of triangular region ABC above?
(1) The product of BD and AC is 20.
(2) x =45
Geometry Triangles; Area
e area of ΔABC BD AC
2
=×.
(1) e product of BD and AC is given as
20, so the area of ΔABC is 20
2 or 10;
SUFFICIENT.
(2) With the measurement of x being 45, it is
concluded that Δ ABD is a 45–45–90 right
triangle, where the length of side BD is
equal to the length of side AD . However,
with no lengths of any side known, there
is not enough information to calculate the
area; NOT sufficient.
e correct answer is A;
statement 1 alone is sufficient.
347. In the xy ‐coordinate plane, is point R equidistant from
points (–3,–3) and (1,–3) ?
(1) The x ‐coordinate of point R is –1.
(2) Point R lies on the line y = –3.
Algebra Coordinate geometry
Determine if point R is equidistant from (–3,–3)
and (1,–3). Letting R = ( x , y ), then R will be
equidistant from (–3,–3) and (1,–3) if and only
if R lies on the perpendicular bisector of the line
segment with endpoints (–3,–3) and (1,–3), or
equivalently, if and only if R lies on the vertical
line that consists of all points with x ‐coordinate
equal to 31
21
−+ =− . erefore, determine if x = –1.
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(1) Given that x = –1, then R will be
equidistant from (–3,–3) and (1,–3);
SUFFICIENT.
(2) Given that y = –3, then both x = –1 and
x ≠ –1 are possible; NOT su cient.
Alternatively, letting R = ( x , y ), then R will be
equidistant from (–3,–3) and (1,–3) if and only if
the distance between ( x , y ) and (–3,–3) is the same
as the distance between ( x , y ) and (1,–3), or if and
only if xy xy( 3)( 3) (1)( 3)
22 22
+++= −++
or if and only if ( x + 3)
2 + ( y + 3)
2 =
( x −1)
2 + ( y + 3)
2 , or if and only if
( x + 3)
2 = ( x −1)
2 .
(1) Given that x = –1, then (–1 + 3)
2 = 4 and
(–1−1)
2 = 4; SUFFICIENT.
(2) Given that y = –3, then it is impossible
to determine if ( x + 3)
2 = ( x −1)
2 ; NOT
su cient.
e correct answer is A;
statement 1 alone is su cient.
348. What is the ratio of the average (arithmetic mean)
height of students in class X to the average height of
students in class Y ?
(1) The average height of the students in class X is
120 centimeters.
(2) The average height of the students in class X
and class Y combined is 126 centimeters.
Arithmetic Statistics
(1) Given that the average height of the
students in class X is 120cm, but given no
information about the average height of the
students in class Y, the desired ratio cannot
be determined; NOT su cient.
(2) Given that the average height of the
students in class X and class Y combined
is 126cm, the ratio of the averages of the
individual classes cannot be determined. For
example, if class X consists of 10 students,
each of whom has height 120cm, and
class Y consists of 10students, each of
whom has height 132 cm, then the average
height of the students in class X and classY
combined is 10(120) 10(132)
20
+=126cm
and the ratio of the averages of the
individual classes is 120
132 . However, if
class X consists of 10 students, each of
whom has height 120 cm and class Y
consists of 20 students, each of whom has
height 129 cm, then the average height
of the students in class X and class Y
combined is 10(120) 20(129)
30 126
+=cm
and the ratio of the averages of the
individual classes is 120
129 ; NOT su cient.
Taking (1) and (2) together is of no more help
than either (1) or (2) taken separately because
the same examples used to show that (2) is not
su cient include the information from (1).
e correct answer is E;
both statements together are still not su cient.
349. Is the positive two‐digit integer N less than 40 ?
(1) The units digit of N is 6 more than the tens digit.
(2) N is 4 less than 4 times the units digit.
Arithmetic Place value
Determine if the two‐digit integer N is less than
40. Letting the tens digit be t and the units digit
be u , then N = 10 t + u . Determine if 10 t + u < 40.
(1) Given that u = t + 6, then
N = 10 t + ( t + 6) = 11 t + 6. Since u is a digit,
u = t + 6 ≤ 9, so t ≤ 3. erefore,
N = 11 t + 6 ≤ 11(3) + 6 = 39;
SUFFICIENT.
(2) Given that N = 4 u −4, then since u is a
digit and u ≤ 9, it follows that
N = 4 u −4 ≤ 4(9)−4 = 32; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
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333
6.5 Data Suffi ciency Answer Explanations
350. If 2
x + y
= 4
8 , what is the value of y ?
(1) x
2 = 81
(2) x − y = 2
Algebra Exponents
Since 4
8 = (2
2 )
8 = 2
16 , the equation 2
x + y = 4
8
becomes 2
x + y = 2
16 , which is equivalent to
x + y = 16.
(1) Given that x
2 = 81, then both x = 9 and
x = –9 are possible. erefore, y = 7 is possible
(choose x = 9) and y = 25 is possible (choose
x = –9); NOT su cient.
(2) Given that x − y = 2, it follows that
– x + y = –2. Adding the last equation
to x + y = 16 gives 2 y = 14, or y = 7;
SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
351. Each week a certain salesman is paid a xed amount
equal to $300, plus a commission equal to 5 percent
of the amount of his sales that week over $1,000.
What is the total amount the salesman was paid last
week?
(1) The total amount the salesman was paid last
week is equal to 10 percent of the amount of his
sales last week.
(2) The salesman’s sales last week totaled $5,000.
Algebra Applied problems
Let P be the salesman’s pay for last week
and let S be the amount of his sales last week.
en P = 300 + 0.05( S − 1,000). Determine the
value of P .
(1) Given P =0.10 S , then 0.10 S =
300 + 0.05( S − 1,000). is equation can
be solved for a unique value of S , from
which the value of P can be determined;
SUFFICIENT.
(2) Given S = 5,000, then P =
300 + 0.05(5,000− 1,000); SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
352. At a bakery, all donuts are priced equally and all bagels
are priced equally. What is the total price of 5 donuts
and 3 bagels at the bakery?
(1) At the bakery, the total price of 10 donuts and
6bagels is $12.90.
(2) At the bakery, the price of a donut is $0.15 less
than the price of a bagel.
Algebra Simultaneous equations
Let x be the price, in dollars, of each donut and
let y be the price, in dollars, of each bagel. Find
the value of 5 x+ 3 y .
(1) Given that 10 x + 6 y = 12.90, since
xy xy53 1
2(10 6 )+= +, it follows that
+=xy53 1
2(12.90); SUFFICIENT.
(2) Given that x = y − 0.15, then 5 x + 3 y =
5( y −0.15) + 3 y = 8 y −0.75, which varies as
y varies; NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
C
B
A
D
353. In the gure above, is the area of triangular region
ABC equal to the area of triangular region DBA ?
(1) ( AC )
2 = 2( AD )
2
(2)
Δ ABC is isosceles.
Geometry Triangles; Area
Determine whether =AC CB AD AB
1
2()()
1
2()()
or, equivalently, whether ( AC )( CB ) = ( AD )( AB ).
(1) Given that ( AC )
2 = 2( AD )
2 , then 2 and 1
could be the values of AC and AD ,
respectively. If, for example, =CB 2, then
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()()
=+=AB 222
22
by the
Pythagorean theorem applied to Δ ABC .
Hence, =AC CB()()(2)(2)
and
( AD )( AB ) = (1)(2), from which it follows
that ( AC )( CB ) = ( AD )( AB ). On the other
hand, if CB = 1, then
()
=+=AB 21 3
22
by the Pythagorean theorem applied to
Δ ABC . Hence, =AC CB()()(2)(1)
and
=AD AB()()(1)(3)
, from which it follows
that ( AC )( CB ) ≠ ( AD )( AB ); NOT su cient.
(2) Given that Δ ABC is isosceles then, by
varying the value of AD , the area of
Δ ABC may or may not be equal to the area
of Δ DBA . For example, if AC = CB = 1, then
( AC )( CB ) = (1)(1) = 1 and AB = 2 by the
Pythagorean theorem applied to Δ ABC . If
==
⎛
⎝
⎜⎞
⎠
⎟=AD AD AB
1
2,then( )( ) 1
2(2) 1
,
and ( AC )( CB ) = ( AD )( AB ). On the other
hand, if AD= 1, ==AD AB()()(1)(2)2
and ( AC )( CB ) ≠ ( AD )( AB ); NOT su cient.
Given (1) and (2) together, let AC = CB = x be
the length of the legs of the isosceles triangle
ABC . en, from ( AC )
2 = 2( AD )
2 , it follows that
x
2 = 2( AD )
2 , and hence =AD x
2. Also, by the
Pythagorean theorem applied to Δ ABC , it
follows that =+=AB x x x 2
22 . erefore,
it follows that ( AC )( CB ) = ( x )( x ) = x
2 and
()
=⎛
⎝
⎜⎞
⎠
⎟=AD AB xxx
(
)( ) 222, and so
( AC )( CB ) = ( AD )( AB ).
e correct answer is C;
both statements together are su cient.
354. If r and s are positive integers, can the fraction r
s be
expressed as a decimal with only a nite number of
nonzero digits?
(1) s is a factor of 100.
(2) r is a factor of 100.
Arithmetic Properties of numbers
Determine if r
s, where r and s are positive
integers, can be expressed as a decimal with a
nite number of nonzero decimal digits.
(1) It is given that s is a factor of 100 and so
s = 1, 2, 4, 5, 10, 20, 25, 50, or 100. is
means that r
s must be one of the quotients
rrrr r r r r
1,2,4,5,10 ,20 ,25 ,50 or r
100 .
us,
r
s must be one of the products r (1),
r (0.5), r (0.25), r (0.20), r (0.1), r (0.05) r (0.04),
r (0.02), or r (0.01). In each case, r
s is the
product of an integer and a decimal with a
nite number of nonzero digits, and
hence, r
s can be expressed as a decimal with
a nite number of nonzero digits. In fact,
it su ces to note this is true for r
100, since
each of the other possibilities is a positive
integer times r
100 (for example, r
20 is
5 times r
100); SUFFICIENT.
(2) It is given that r is a factor of 100. If r = 4
and s= 5, then r
s = 0.8, which is a decimal
with a nite number of nonzero digits.
On the other hand, if r = 4 and s = 7, then
=
r
s0.571428, which is not a decimal with
a nite number of nonzero digits; NOT
su cient.
e correct answer is A;
statement 1 alone is su cient.
355. If r > 0 and s > 0, is <
r
s
s
r ?
(1) =
r
s3
1
4
(2) s = r + 4
Algebra Ratios
Given positive numbers r and s , determine if
<
r
s
s
r.
(1) If =
r
s3
1
4, then =
r
s
3
4, =
s
r
4
3, and so
<
r
s
s
r, since <
3
4
4
3; SUFFICIENT.
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335
6.5 Data Suffi ciency Answer Explanations
(2) If s = r +4, then =+
r
s
r
r4 and s
r= +r
r
4.
Since r +4> r , +
r
r4<1 and +r
r
4>1,
so <
r
s
s
r; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
356. If k is an integer such that 56 < k < 66, what is the
value of k ?
(1) If k were divided by 2, the remainder would be 1.
(2) If k + 1 were divided by 3, the remainder would
be 0.
Arithmetic Properties of integers
Determine the value of the integer k , where
56 < k < 66.
(1) It is given that the remainder is 1 when k
is divided by 2, which implies that k is odd.
erefore, the value of k can be 57, 59, 61,
63, or 65; NOT su cient.
(2) It is given that the remainder is 0 when
k + 1 is divided by 3, which implies that
k + 1 is divisible by 3. Since 56 < k < 66
(equivalently, 57 < k + 1 < 67), the value
of k + 1 can be 60, 63, or 66 so the value
of k can be 59, 62, or 65; NOT su cient.
Taking (1) and (2) together, 59 and 65 appear
in both lists of possible values for k ; NOT
su cient.
e correct answer is E;
both statements together are still not su cient.
357. If x is a positive integer, then is x prime?
(1) 3 x + 1 is prime.
(2) 5 x + 1 is prime.
Arithmetic Properties of numbers
Determine if the positive integer x is prime.
(1) is indicates that 3 x +1 is prime. If
x =2, then 3 x +1=7 is prime and so is x .
However, if x =6, then 3 x +1=19 is prime,
but 6 is not prime; NOT su cient.
(2) is indicates that 5 x +1 is prime. If x =2,
then 5 x +1=11 is prime and so is x .
However, if x =6, then 5 x +1=31 is prime,
but 6 is not prime; NOT su cient.
Because the same examples were used to establish
that neither (1) nor (2) is su cient, it is not
possible to determine whether x is prime from
the given information.
e correct answer is E;
both statements together are still not su cient.
k , n , 12, 6, 17
358. What is the value of n in the list above?
(1) k < n
(2) The median of the numbers in the list is 10.
Arithmetic Statistics
Given the list k , n , 12, 6, 17, determine the value
of n .
(1) Although k < n , no information is given
about the value of k or n ; NOT su cient.
(2) Since the median of the numbers in the list
is 10 and there are 5 numbers in the list,
10 is one of those 5 numbers. erefore,
n = 10 or k = 10. If n = 10, then the value
of n has been determined. However, if
k = 10, then n can be any number that
is 10 or less, so the value of n cannot be
determined; NOT su cient.
Taking (1) and (2) together, if k < n and the
median of the list is 10, then 12 and 17 are to
the right of the median and the list in ascending
order is either 6, k , n , 12, 17 or k , 6, n , 12, 17. In
either case, n is the middle number, and since the
median is 10, n =10.
e correct answer is C;
both statements together are su cient.
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359. If x and y are integers, what is the value of x + y ?
(1)
<+<
xy
324
(2) 2 < x < y < 5
Arithmetic Computation with integers
Determine the value of x + y for integers x and y .
(1) Given that 3< +xy
2<4, then 6< x + y <8.
Since x + y is an integer and 7 is the
only integer greater than 6 and less than
8, it follows that the value of x + y is 7;
SUFFICIENT.
(2) Given that 2 < x < y < 5, then 2 < x < 5, and
hence x = 3 or x = 4. Likewise, 2 < y < 5,
and hence y = 3 or y = 4. With the
additional restriction that x < y , it follows
that x = 3 and y = 4, and thus x + y = 7;
SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
360. Last year, if Arturo spent a total of $12,000 on his
mortgage payments, real estate taxes, and home
insurance, how much did he spend on his real estate
taxes?
(1) Last year, the total amount that Arturo spent on
his real estate taxes and home insurance was
33 1
3percent of the amount that he spent on his
mortgage payments.
(2) Last year, the amount that Arturo spent on his
real estate taxes was 20 percent of the total
amount he spent on his mortgage payments and
home insurance.
Arithmetic Applied problems
Let M , R , and H be the amounts that Arturo
spent last year on mortgage payments, real estate
taxes, and home insurance, respectively. Given that
++ =MRH12, 000, determine the value of R .
(1) Given that +=RH M
1
3 and MRH++ =
12,000, then +=MM
1
312,000, or
M =9,000. However, the value of R cannot
be determined, since it is possible that
R =2,000 (use M =9,000 and H =1,000)
and it is possible that R =1,000 (use
M =9,000 and H =2,000); NOT su cient.
(2) Given that =+RMH
1
5()
, or 5 R = M + H
and M + R + H = 12,000, which can be
rewritten as ( M + H ) + R = 12,000, then
5 R + R = 12,000, or R =2,000;
SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
361. If a , b , c , and d are positive numbers, is <
a
b
c
d ?
(1)
<−
−
ca
db
0
(2)
⎛
⎝
⎜⎞
⎠
⎟<
ad
bc
ad
bc
2
Algebra Inequalities
Determine whether <
a
b
c
d, where a , b , c , and d are
positive numbers.
(1) Given that <−
−
ca
db
0, then a = 2, b = 3, c = 6,
and d = 8 are possible values for a , b , c ,
and d because −
−=−
−=
ca
db
62
83
4
5 and >
4
50.
For these values, <
a
b
c
d is true because <
2
3
6
8.
On the other hand, a = 4, b = 6, c = 2, and
d = 3 are also possible values of a , b , c , and
d because −
−=−
−=
ca
db
24
36
2
3 and >
2
30. For
these values, <
a
b
c
d is false because =
4
6
2
3;
NOT su cient.
(2) Given that ⎛
⎝⎞
⎠<
ad
bc
ad
bc
2
, then
<
ad
bc 1 dividing both sides by the
positive number ad
bc
<
ad
bc multiplying both sides by the
positive number c
<
a
b
c
d dividing both sides by the positive
number d; SUFFICIENT
e correct answer is B;
statement 2 alone is su cient.
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6.5 Data Suffi ciency Answer Explanations
362. Is the number of members of Club X greater than the
number of members of Club Y ?
(1) Of the members of Club X, 20 percent are also
members of Club Y.
(2) Of the members of Club Y, 30 percent are also
members of Club X.
Arithmetic Sets
Let a be the number of members in Club X that
do not belong to Club Y, let b be the number of
members in Club Y that do not belong to Club X,
and let c be the number of members that belong to
both Club X and to Club Y. Determine whether
a + c > b + c , or equivalently, whether a > b .
(1) If a = 80, b =79, and c = 20, then 20 percent
of the members of Club X are also members
of Club Y (because c = 20 is 20 percent of
a + c = 100) and a > b is true. However, if
a =80, b = 80, and c= 20, then 20 percent
of the members of Club X are also members
of Club Y (because c = 20 is 20 percent of
a + c = 100) and a > b is false. erefore, it
cannot be determined whether a > b ; NOT
su cient.
(2) If a = 71, b = 70, and c = 30, then 30 percent
of the members of Club Y are also members
of ClubX (because c = 30 is 30 percent of
b + c = 100) and a > b is true. However, if
a =70, b =70, and c = 30, then 30 percent of
the members of Club Y are also members
of Club X (because c= 30 is 30 percent of
b + c = 100) and a > b is false. erefore, it
cannot be determined whether a > b ; NOT
su cient.
Now assume both (1) and (2). From (1) it follows
that +
c
ac
= 0.20=1
5, or 5 c = a + c , and so a = 4c.
From (2) it follows that +
c
bc
= 0.30= 3
10, or
10 c= 3 b+ 3 c , and so 7 c = 3 b and =bc
7
3. Since
4 c>
7
3 c (from the statements it can be deduced
that c > 0), it follows that a > b . erefore, (1) and
(2) together are su cient.
e correct answer is C;
both statements together are su cient.
qprst
363. On the number line above, p , q , r , s , and t are ve
consecutive even integers in increasing order. What is
the average (arithmetic mean) of these ve integers?
(1) q + s = 24
(2) The average (arithmetic mean) of q and r is 11.
Arithmetic Properties of numbers
Since p , q , r , s , and t are consecutive even integers
listed in numerical order, the 5 integers can also be
given as p , p + 2, p + 4, p + 6, and p + 8. Determine
the average of these 5 integers, which is the value
of ppppp( 2)( 4)( 6)( 8)
5
++++++++=
pp
520
54
+=+
(1) Given that q + s =24, then
( p + 2) + ( p + 6) = 24.
erefore, 2 p + 8 = 24, or p = 8, and hence
p + 4 =12; SUFFICIENT.
(2) Given that +=
qr
211, then q + r =(2)(11) = 22,
or ( p + 2) + ( p + 4) = 22. erefore,
2 p + 6 = 22, or p = 8, and hence p + 4 = 12;
SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
364. If x
⎡
⎢⎤
⎥ denotes the least integer greater than or equal
to x , is x0
⎡
⎢⎤
⎥= ?
(1) –1 < x < 1
(2) x < 0
Algebra Functions
Determine if ⎡
⎢⎤
⎥
x, the least integer greater than
or equal to x , is equal to 0, which is the same as
determining if x satis es –1 < x ≤ 0.
(1) Given that –1 < x < 1, then it is possible
that ⎡
⎢⎤
⎥=x0 (for example, if x = 0, then
⎡
⎢⎤
⎥=x0) and it is possible that ⎡
⎢⎤
⎥≠x0 (for
example, if =x1
2, then ⎡
⎢⎤
⎥=≠x10
); NOT
su cient.
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(2) Given that x < 0, then it is possible that
⎡
⎢⎤
⎥=x0 (for example, if =−x1
2, then ⎡
⎢⎤
⎥=x0)
and it is possible that ⎡
⎢⎤
⎥≠x0 (for example,
if x = –5, then ⎡
⎢⎤
⎥=− ≠x50
); NOT
su cient.
Taking (1) and (2) together gives –1 < x < 0,
which implies that ⎡
⎢⎤
⎥=x0.
e correct answer is C;
both statements together are su cient.
365. If x and y are integers, is x > y ?
(1) x + y > 0
(2) y
x < 0
Arithmetic Properties of integers
Determine if the integer x is greater than the
integer y .
(1) It is given that x + y > 0, and so – x < y .
If, for example, x = –3 and y = 4, then
x + y = –3 + 4 = 1 > 0 and x < y . On the
other hand, if x = 4 and y = –3, then
x+ y = 4−3 = 1 > 0 and x > y ; NOT
su cient.
(2) It is given that y
x < 0, so y < 0. If, for
example, x= 3 and y = –2,
then (–2)
3 = –8 < 0 and x > y . On the
other hand, if x = –3 and y = –2, then
(–2)
–3 =– 1
8<0 and x < y ; NOT su cient.
Taking (1) and (2) together, from (2) y is
negative and from (1) – x is less than y . erefore,
– x is negative, and hence x is positive. Since x is
positive and y is negative, it follows that x > y.
e correct answer is C;
both statements together are su cient.
366. If r and s are the roots of the equation x
2 + bx + c = 0,
where b and c are constants, is rs < 0 ?
(1) b < 0
(2) c < 0
Algebra Second-degree equations
Determine whether the product of the roots to
x
2 + bx + c = 0, where b and c are constants, is
negative.
If r and s are the roots of the given equation, then
( x − r )( x − s ) = x
2 + bx + c . is implies that
x
2 −( r + s ) x + rs = x
2 + bx + c , and so rs = c .
erefore, rs is negative if and only if c is negative.
(1) Given that b < 0, then c could be negative or
positive. For example, if b = –1 and
c = –6, then the given equation would be
x
2 − x −6 = ( x −3)( x + 2) = 0, and the
product of its roots would be (3)(–2), which
is negative. On the other hand, if b = –6 and
c = 5, then the given equation would be
x
2 −6 x + 5 = ( x −5)( x −1) = 0, and the
product of its roots would be (5)(1), which
is positive; NOT su cient.
(2) Given that c < 0, it follows from the
explanation above that rs < 0; SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
k ft
k ft
15 ft
15 ft
367. The gure above represents an L‐shaped garden. What
is the value of k ?
(1) The area of the garden is 189 square feet.
(2) The perimeter of the garden is 60 feet.
Geometry Polygons
(1) Given that the area of the garden is 189 ft
2 ,
and observing that area of the garden can
be calculated by imagining the garden as
a square with dimensions 15 ft by 15 ft
from which its upper‐right square corner
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6.5 Data Suffi ciency Answer Explanations
with dimensions (15− k ) ft by (15− k ) ft
is removed, it follows that
189 = (15)
2 −(15− k )
2 . erefore, (15− k )
2 =
225−189 = 36, so 15− k = 6 or 15− k = –6.
e gure implies 15− k > 0, so it follows
that 15− k = 6, or k = 9; SUFFICIENT.
(2) Given that the perimeter of the garden is
60 ft, and because 15 + 15 + k + (15− k ) +
(15− k ) + k = 60, any value of k between 0
and 15 is possible, since for any such value
of k the sum of the lengths of all the sides
would be 60 ft; NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
368. The only articles of clothing in a certain closet are
shirts, dresses, and jackets. The ratio of the number
of shirts to the number of dresses to the number of
jackets in the closet is 9:4:5, respectively. If there are
more than 7dresses in the closet, what is the total
number of articles of clothing in the closet?
(1) The total number of shirts and jackets in the
closet is less than 30.
(2) The total number of shirts and dresses in the
closet is 26.
Arithmetic Ratio and proportion
Letting s , d , and j represent, respectively, the
numbers of shirts, dresses, and jackets in the
closet, then s =9 x , d =4 x , and j =5 x , where x is
a positive integer. It is given that 4 x >7, and so
4 x ≥8 or x ≥2 since x is an integer. Determine
the value of 9 x +4 x +5 x =18 x .
(1) is indicates that 9 x +5 x <30, and so
14 x ≤28 or x ≤2 since x is an integer. It
follows from x ≥2 and x ≤2 that x =2 and
18 x =36; SUFFICIENT.
(2) is indicates that 9 x +4 x =26 or
13 x =26, or x =2. It follows that 18 x =36;
SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
QR
PT
S
O
x°
TOTAL EXPENSES FOR THE
FIVE DIVISIONS OF COMPANY H
369. The gure above represents a circle graph of
CompanyH’s total expenses broken down by the
expenses for each of its ve divisions. If O is the center
of the circle and if Company H’s total expenses are
$5,400,000, what are the expenses for Division R ?
(1) x = 94
(2) The total expenses for Divisions S and T are
twice as much as the expenses for Division R.
Geometry Circles
In this circle graph, the expenses of Division R
are equal to the value of x
360 multiplied by
$5,400,000, or $15,000 x . erefore, it is necessary
to know the value of x in order to determine the
expenses for Division R.
(1) e value of x is given as 94, so the
expenses of Division R can be determined;
SUFFICIENT.
(2) is gives a comparison among the expenses
of some of the divisions of Company H, but
no information is given about the value of x ;
NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
370. If x is negative, is x < –3 ?
(1) x
2 > 9
(2) x
3 < –9
Algebra Properties of numbers
(1) Given that x
2 > 9, it follows that x <−3 or
x > 3, a result that can be obtained in a
variety of ways. For example, consider the
equivalent inequality
(
)
>x9
2 that reduces
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to >x3, or consider when the two factors
of x2 − 9 are both positive and when the
two factors of x2 − 9 are both negative, or
consider where the graph of the parabola
y = x2 − 9 is above the x ‐axis, etc. Since it is
also given that x is negative, it follows that
x < –3; SUFFICIENT.
(2) Given that x
3 < –9, if x = –4, then x
3 = –64,
and so x
3 <–9 and it is true that x < –3.
However, if x = –3, then x
3 = –27, and so
x
3 < –9, but it is not true that x < –3;
NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
371. What is the number of cans that can be packed in a
certain carton?
(1) The interior volume of this carton is 2,304 cubic
inches.
(2) The exterior of each can is 6 inches high and has
a diameter of 4 inches.
Geometry Rectangular solids and cylinders
(1) No information about the size of the cans is
given; NOT su cient.
(2) No information about the size of the carton
is given; NOT su cient.
Taking (1) and (2) together, there is still not
enough information to answer the question. If
the carton is a rectangular solid that is 1 inch
by 1inch by 2,304 inches and the cans are
cylindrical with the given dimensions, then 0cans
can be packed into the carton. However, if the
carton is a rectangular solid that is 16inches
by 12inches by 12 inches and the cans are
cylindrical with the given dimensions, then
1 or more cans can be packed into the carton.
e correct answer is E;
both statements together are still not su cient.
rst
uvw
xyz
372. Each of the letters in the table above represents one
of the numbers 1, 2, or 3, and each of these numbers
occurs exactly once in each row and exactly once in
each column. What is the value of r ?
(1) v + z = 6
(2) s + t + u + x = 6
Arithmetic Properties of numbers
In the following discussion, “row/column
convention” means that each of the numbers 1, 2,
and 3 appears exactly once in any given row and
exactly once in any given column.
(1) Given that v + z = 6, then both v and z
are equal to 3, since no other sum of the
possible values is equal to 6. Applying the
row/column convention to row 2, and then
to row 3, it follows that neither u nor x can
be 3. Since neither u nor x can be 3, the
row/column convention applied to column 1
forces r to be 3; SUFFICIENT.
(2) If u = 3, then s + t + x = 3. Hence, s = t =
x = 1, since the values these variables can
have does not permit another possibility.
However, this assignment of values would
violate the row/column convention for
row 1, and thus u cannot be 3. If x = 3, then
s + t + u = 3. Hence, s = t = u =1, since the
values these variables can have does not
permit another possibility. However, this
assignment of values would violate the
row/column convention for row 1, and thus
x cannot be 3. Since neither u nor x can be
3, the row/column convention applied to
column 1 forces r to be 3; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
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6.5 Data Suffi ciency Answer Explanations
373. Material A costs $3 per kilogram, and Material B costs
$5 per kilogram. If 10 kilograms of MaterialKconsists
of x kilograms of Material A and y kilograms of
MaterialB, is x > y ?
(1) y > 4
(2) The cost of the 10 kilograms of Material K is
less than $40.
Algebra Inequalities
Since x + y = 10, the relation x > y is equivalent to
x > 10 − x , or x > 5.
(1) e given information is consistent with
x = 5.5 and y = 4.5, and the given information
is also consistent with x = y =5. erefore,
it is possible for x > y to be true and it is
possible for x > y to be false; NOT su cient.
(2) Given that 3 x + 5 y < 40, or
3 x +5(10 − x ) < 40, then 3 x − 5 x < 40 − 50.
It follows that −2 x < –10, or x > 5;
SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
374. At what speed was a train traveling on a trip when it
had completed half of the total distance of the trip?
(1) The trip was 460 miles long and took 4 hours to
complete.
(2) The train traveled at an average rate of
115 miles per hour on the trip.
Arithmetic Applied problems
Determine the speed of the train when it had
completed half the total distance of the trip.
(1) Given that the train traveled 460 miles
in 4 hours, the train could have traveled
at the constant rate of 115miles per hour
for 4 hours, and thus it could have been
traveling 115 miles per hour when it had
completed half the total distance of the
trip. However, the train could have traveled
150 miles per hour for the rst 2 hours
(a distance of 300 miles) and 80 miles per
hour for the last 2hours (a distance of
160 miles), and thus it could have been
traveling 150 miles per hour when it had
completed half the total distance of the trip;
NOT su cient.
(2) Given that the train traveled at an average
rate of 115 miles per hour, each of the
possibilities given in the explanation for
(1) could occur, since 460 miles in 4hours
gives an average speed of =
460
4115 miles
per hour; NOT su cient.
Assuming (1) and (2), each of the possibilities
given in the explanation for (1) could occur.
erefore, (1) and (2) together are not su cient.
e correct answer is E;
both statements together are still not su cient.
375. Tom, Jane, and Sue each purchased a new house. The
average (arithmetic mean) price of the three houses
was $120,000. What was the median price of the
three houses?
(1) The price of Tom’s house was $110,000.
(2) The price of Jane’s house was $120,000.
Arithmetic Statistics
Let T , J , and S be the purchase prices for Tom’s,
Jane’s, and Sue’s new houses. Given that
the average purchase price is 120,000, or
T + J + S =3(120,000), determine the median
purchase price.
(1) Given T = 110,000, the median could be
120,000 (if J = 120,000 and S = 130,000) or
125,000 (if J = 125,000 and S = 125,000);
NOT su cient.
(2) Given J = 120,000, the following two cases
include every possibility consistent with
T + J+S = (3)(120,000), or
T +S = (2)(120,000).
(i) T = S = 120,000
(ii) One of T or S is less than 120,000 and
the other is greater than 120,000.
In each case, the median is clearly 120,000;
SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
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376. What is the value of x if x3 < x2 ?
(1) –2 < x < 2
(2) x is an integer greater than –2.
Algebra Inequalities
e inequality x3<x2 is equivalent to x3−x2<0,
or x2(x−1)<0. Since this inequality is false
for x=0, it follows that x≠0, and hence x2>0.
erefore, x2(x−1)<0 can only hold if x−1<0,
or if x<1. us, the problem is equivalent to
determining the value of x given that x≠0 and
x<1.
(1) Given that –2<x<2, it is not possible to
determine the value of x. For example, the
value of x could be –1 (note that –1<1)
and the value of x could be 0.5 (note that
0.5<1); NOT su cient.
(2) Given that the value of x is an integer
greater than –2, then the value of x must
be among the integers –1, 0, 1, 2, 3, ....
However, from the discussion above, x≠0
and x<1, so the value of x can only be –1;
SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
377. For any integers x and y , min( x , y ) and max( x , y ) denote
the minimum and the maximum of x and y , respectively.
For example, min(5, 2)=2 and max(5, 2)=5. For
the integer w , what is the value of min(10, w ) ?
(1) w = max(20, z ) for some integer z .
(2) w = max(10, w )
Arithmetic Properties of numbers
If w ≥ 10, then (10, w ) = 10, and if w < 10,
then (10, w )= w . erefore, the value of
min(10, w ) can be determined if the value of
w can be determined.
(1) Given that w = max(20, z ) then w ≥ 20.
Hence, w ≥ 10, and so min(10, w )= 10;
SUFFICIENT.
(2) Given that w = max(10, w ), then w ≥ 10,
and so min(10, w ) = 10; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
378. A certain bookcase has 2 shelves of books. On the
upper shelf, the book with the greatest number of
pages has 400pages. On the lower shelf, the book
with the least number of pages has 475 pages. What
is the median number of pages for all of the books on
the 2 shelves?
(1) There are 25 books on the upper shelf.
(2) There are 24 books on the lower shelf.
Arithmetic Statistics
(1) e information given says nothing about
the number of books on the lower shelf. If
there are fewer than 25 books on the lower
shelf, then the median number of pages will
be the number of pages in one of the books
on the upper shelf or the average number
of pages in two books on the upper shelf.
Hence, the median will be at most 400. If
there are more than 25books on the lower
shelf, then the median number of pages will
be the number of pages in one of the books
on the lower shelf or the average number
of pages in two books on the lower shelf.
Hence, the median will be at least 475;
NOT su cient.
(2) An analysis very similar to that used in (1)
shows the information given is not su cient
to determine the median; NOT su cient.
Given both (1) and (2), it follows that there is
a total of 49 books. erefore, the median will
be the 25th book when the books are ordered
by number of pages. Since the 25th book in this
ordering is the book on the upper shelf with the
greatest number of pages, the median is 400.
erefore, (1) and (2) together are su cient.
e correct answer is C;
both statements together are su cient.
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6.5 Data Suffi ciency Answer Explanations
ABCD
E
379. In the gure above, points A , B , C , D , and E lie on a
line. A is on both circles, B is the center of the smaller
circle, C is the center of the larger circle, D is on the
smaller circle, and E is on the larger circle. What is the
area of the region inside the larger circle and outside
the smaller circle?
(1) AB = 3 and BC = 2
(2) CD = 1 and DE = 4
Geometry Circles
If R is the radius of the larger circle and r is the
radius of the smaller circle, then the desired area
is π R
2 −π r
2 . us, if both the values of R and r
can be determined, then the desired area can be
determined.
(1) Given that AB =r = 3 and BC = 2, then
AB + BC = R = 3 + 2 = 5; SUFFICIENT.
(2) Given that CD = 1 and DE = 4, then
CD + DE = R = 1 + 4 = 5. Since AE is a
diameter of the larger circle, then
AD + DE = 2R . Also, since AD is a diameter
of the smaller circle, then AD = 2r . us,
2 r + DE =2 R or 2 r +4=10, and so r =3;
SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
380. In planning for a trip, Joan estimated both the distance
of the trip, in miles, and her average speed, in miles
per hour. She accurately divided her estimated
distance by her estimated average speed to obtain an
estimate for the time, in hours, that the trip would take.
Was her estimate within 0.5 hour of the actual time
that the trip took?
(1) Joan’s estimate for the distance was within
5miles of the actual distance.
(2) Joan’s estimate for her average speed was within
10 miles per hour of her actual average speed.
Arithmetic Applied problems; Estimating
(1) Given that Joan’s estimate for the distance
was within 5 miles of the actual distance,
it is not possible to determine whether her
estimate for the time was within 0.5 hour
without information about her estimated
average speed. For example, if her estimated
distance was 20miles and was within
5 miles of the actual distance, then the
actual distance would be between 15 and
25miles. If her estimated speed was
20 miles per hour (mph) and was within,
say, 10 mph of her actual speed, then
her actual speed would be between 10 and
30 mph. Her estimated time would then
be 20
20 = 1.0 hour and the actual time would
be between 15
30 = 0.5 hour (least distance
over greatest speed) and 25
10 = 2.5 hours
(greatest distance over least speed). Since
1.0 hour is between 0.5 hour and 2.5 hours,
her estimate for the time could equal the
actual time, and thus it is possible that
her estimate of the time is within 0.5 hour
of the actual time. However, her estimate
for the time could be as much as
2.5−1.0 = 1.5 hours over the actual time,
and thus it is possible that her estimate
of the time is not within 0.5 hour; NOT
su cient.
(2) Given that Joan’s estimate for her average
speed was within 10 miles per hour of her
actual average speed, the same examples
used in (1) can be used to show that it
cannot be determined whether her estimate
for the time would be within 0.5 hour of the
actual time; NOT su cient.
Taking (1) and (2) together is of no more help
than either (1) or (2) taken separately because
the same examples used to show that (1) is not
su cient also show that (2) is not su cient.
e correct answer is E;
both statements together are still not su cient.
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381. A certain list consists of 3 different numbers. Does the
median of the 3 numbers equal the average (arithmetic
mean) of the 3 numbers?
(1) The range of the 3 numbers is equal to twice the
difference between the greatest number and the
median.
(2) The sum of the 3 numbers is equal to 3 times
one of the numbers.
Arithmetic Statistics
Let the numbers be x , y , and z so that x < y < z .
Determine whether y = ++xyz
3, or equivalently,
whether 3 y = x + y + z , or equivalently,
whether 2 y = x + z .
(1) Given that the range is equal to twice the
di erence between the greatest number and
the median, it follows that z − x = 2( z − y ),
or z − x = 2 z −2 y , or 2 y = x + z ;
SUFFICIENT.
(2) Given that the sum of the 3 numbers equals
3times one of the numbers, it follows that
x + y + z = 3 x or x + y + z = 3 y or
x + y + z = 3 z . If x + y + z = 3 x , then
y + z = 2 x , or ( y − x ) + ( z − x ) = 0. Also,
if x + y + z = 3 z , then x + y = 2 z , or
0 = ( z − x ) + ( z − y ). In each of these cases,
the sum of two positive numbers is zero,
which is impossible. erefore, it must
be true that x + y + z = 3 y , from which it
follows that x + z = 2 y , and hence by the
initial comments, the median of the
3 numbers equals the average of the
3 numbers; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
382. Line ℓ lies in the xy-plane and does not pass through
the origin. What is the slope of line ℓ ?
(1) The x-intercept of line ℓ is twice the y-intercept
of line ℓ.
(2) The x- and y-intercepts of line ℓ are both positive.
Geometry Coordinate geometry
Since the line does not pass through the origin,
the line is either vertical and given by the
equation x=c for some constantc such that
c≠0, or the line is not vertical and given by the
equation y=mx+b for some constants m and b
such that b≠0. Determine whether the line is not
vertical, and if so, determine the slope of the line,
which is the value of m.
(1) Given that the x-intercept of the line is
twice the y-intercept of the line, it follows
that the line is not vertical, since a vertical
line that does not pass through the origin
will not have a y-intercept. us, the line
is given by the equation y=mx+b. e
x-intercept of the line is the solution to
0=mx+b, or mx=–b, which has solution
x=–b
m, and the y-intercept of the line is b.
erefore, – b
m=2b. Since b≠0, both sides
of the last equation can be divided by b to
get – m
1=2, or m=–1/2; SUFFICIENT.
(2) Given that the x- and y-intercepts of the
line are both positive, it is not possible to
determine the slope of the line. For example,
if the line is given by y=–x+1, then the
x-intercept is 1 (solve –x+1=0), the
y-intercept is 1 (b=1), and the slope is –1.
However, if the line is given by y=–2x+2,
then the x-intercept is 1 (solve –2x+2=0),
the y-intercept is 2 (b=2), and the slope is
–2; NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
y = ax −5
y = x +6
y =3 x + b
383. In the xy ‐plane, the straight‐line graphs of the three
equations above each contain the point ( p , r ). If a and
b are constants, what is the value of b ?
(1) a = 2
(2) r = 17
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6.5 Data Suffi ciency Answer Explanations
Algebra Coordinate geometry
Since ( p , r ) is on each of the lines, each of the
following three equations is true:
(i) r = ap −5
(ii) r = p + 6
(iii) r = 3 p + b
Determine the value of b .
(1) Given that a = 2, Equations (i) and
(ii) become r = 2 p −5 and r = p + 6.
Subtracting equations gives 0 = p −11, or
p = 11. Now using r = p + 6, it follows that
r = 11 + 6 = 17. Finally, using p = 11 and
r = 17 in Equation (iii) gives
17 = 3(11) + b , or b = 17−33 = –16;
SUFFICIENT.
(2) Given that r = 17, Equation (ii) becomes
17 = p + 6, and so p = 17−6 = 11. Using
r = 17 and p = 11, Equation (iii) becomes
17 = 3(11) + b , or b = 17−33 = –16;
SUFFICIENT.
e correct answer is D;
each statement alone is sufficient.
T
U
W
V
S
Q
PR
384. In the gure above, PQR and STU are identical
equilateral triangles, and PQ = 6. What is the perimeter
of polygon PQWTUVR ?
(1) Triangle SWV has perimeter 9.
(2) VW has length 3.5.
Geometry Triangles; Perimeter
(1) Given that triangle SWV has perimeter 9,
the perimeter of polygon PQWTUVR
can be determined, since the perimeter of
polygon PQWTUVR equals the sum of the
perimeters of the two equilateral triangles,
which is 3(6) + 3(6) = 36, minus the
perimeter of triangle SWV ; SUFFICIENT.
Q
T
U
W
V
PR
3.5
3.5
3.5
S
Figure 1
T
U
W
V
S
Q
RP
3.5
Figure 2
(2) Given that VW = 3.5, and using the fact
that the perimeter of polygon PQWTUVR
equals the sum of the perimeters of
the two equilateral triangles, which is
3(6) + 3(6) = 36, minus the perimeter of
triangle SWV , it is not possible to determine
the perimeter of polygon PQWTUVR .
For example, the perimeter of polygon
PQWTUVR could be 36−3(3.5) = 25.5
(arrange triangles PQR and STU so that
VW = WS = SV = 3.5, as shown in Figure 1),
and the perimeter of polygon PQWTUVR
could be greater than 25.5 (arrange triangles
PQR and STU so that VW = 3.5, WS is
slightly greater than 3.5, and SV is close to
0, as shown in Figure 2); NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
385. The range of the numbers in set S is x , and the range
of the numbers in set T is y . If all of the numbers in set
T are also in set S , is x greater than y ?
(1) Set S consists of 7 numbers.
(2) Set T consists of 6 numbers.
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Arithmetic Statistics
Set S has a range of x , set T has a range of y , and
T is a subset of S . Determine if x is greater than y .
(1) It is given that S contains exactly 7 numbers,
but nothing additional is known about T .
us, if S = {1, 2, 3, 4, 5, 6, 7} and
T = {1, 2, 3, 4, 5, 6}, then x = 7−1 = 6,
y = 6−1 = 5, and x is greater than y . On the
other hand, if S = {1, 2, 3, 4, 5, 6, 7} and
T = {1, 3, 4, 5, 6, 7}, then x = 7−1 = 6,
y = 7−1 = 6, and x is not greater than y ;
NOT su cient.
(2) It is given that T contains exactly 6 numbers,
but nothing additional is known about T .
Since the same examples given in (1) can
also be used in (2), it cannot be determined
if x is greater than y ; NOT su cient.
Taking (1) and (2) together, the examples used
in (1) can be used to show that it cannot be
determined if x is greater than y .
e correct answer is E;
both statements together are still not su cient.
386. The hypotenuse of a right triangle is 10 cm. What is
the perimeter, in centimeters, of the triangle?
(1) The area of the triangle is 25 square
centimeters.
(2) The 2 legs of the triangle are of equal length.
Geometry Triangles
If x and y are the lengths of the legs of the
triangle, then it is given that x
2 + y
2 = 100.
Determining the value of x + y + 10, the
perimeter of the triangle, is equivalent to
determining the value of x + y .
(1) Given that the area is 25, then =xy
1
225, or
xy = 50. Since +=++xy x y xy() 2
222 , it
follows that +=+xy( ) 100 2(50)
2, or
+=xy 200; SUFFICIENT.
(2) Given that x = y , since x
2 + y
2 = 100, it
follows that 2 x
2 =100, or =x50. Hence,
+=+= =xyxx x2250
; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
Shipment S1 S2 S3 S4 S5 S6
Fraction of the
Total Value of the
Six Shipments
1
4
1
5
1
6
3
20
2
15
1
10
387. Six shipments of machine parts were shipped from a
factory on two trucks, with each shipment entirely on
one of the trucks. Each shipment was labeled either
S1, S2, S3, S4, S5, or S6. The table shows the value
of each shipment as a fraction of the total value of
the six shipments. If the shipments on the rst truck
had a value greater than 1
2 of the total value of the six
shipments, was S3 shipped on the rst truck?
(1) S2 and S4 were shipped on the rst truck.
(2) S1 and S6 were shipped on the second truck.
Arithmetic Operations on rational numbers
Given that the shipments on the rst truck had
a value greater than 1
2 of the total value of the
6 shipments, determine if S3 was shipped on the
rst truck.
To avoid dealing with fractions, it will be
convenient to create scaled values of the
shipments by multiplying each fractional value
by 60, which is the least common denominator
of the fractions. us, the scaled values associated
with S1, S2, S3, S4, S5, and S6 are 15, 12, 10, 9,
8, and 6, respectively. e given information is
that the scaled value of the shipments on the rst
truck is greater than ⎛
⎝⎞
⎠
1
2(60) = 30.
(1) Given that the rst truck includes
shipments with scaled values 12 and 9, it
may or may not be the case that S3 (the
shipment with scaled value 10) is on the
rst truck. For example, the rst truck could
contain only S2, S3, and S4, for a total
scaled value 12 + 10 + 9 = 31 > 30. Or, the
rst truck could contain only S1, S2, and S4,
for a total scaled value 15 + 12 + 9 = 36 > 30;
NOT su cient.
(2) Given that the second truck includes
shipments with scaled values 15 and 6, the
second truck cannot contain S3. Otherwise,
the second truck would contain shipments
with scaled values 15, 6, and 10, for a total
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347
6.5 Data Suffi ciency Answer Explanations
scaled value 15 + 6 + 10 = 31, leaving
at most a total scaled value 29 (which is
not greater than 30) for the rst truck;
SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
388. If x , y , and z are three‐digit positive integers and if
x = y + z , is the hundreds digit of x equal to the sum
of the hundreds digits of y and z ?
(1) The tens digit of x is equal to the sum of the tens
digits of y and z .
(2) The units digit of x is equal to the sum of the
units digits of y and z .
Arithmetic Place value
Letting x = 100 a + 10 b + c , y = 100 p + 10 q + r ,
and z = 100 t + 10 u + v , where a , b , c , p , q , r , t , u ,
and v are digits, determine if a = p + t .
(1) It is given that b = q + u (which implies that
c + v ≤ 9 because if c + v > 9, then in the
addition process a ten would need to be
carried over to the tens column and b would
be q + u + 1). Since b is a digit, 0 ≤ b ≤ 9.
Hence, 0 ≤ q + u ≤ 9, and so 0 ≤ 10( q + u ) ≤ 90.
erefore, in the addition process, there are
no hundreds to carry over from the tens
column to the hundreds column, so a = p + t ;
SUFFICIENT.
(2) It is given that c = r + v . If x = 687, y = 231,
and z = 456, then, y + z = 231 + 456 =
687 = x , r + v = 1 + 6 = 7 = c , and
p + t = 2 + 4 = 6 = a . On the other hand,
if x = 637, y = 392, and z = 245, then y + z =
392 + 245 = 637 = x , r + v = 2 + 5 = 7 = c ,
and p + t = 3 + 2 = 5 ≠ 6 = a ; NOT
su cient.
e correct answer is A;
statement 1 alone is su cient.
Favorable Unfavorable Not Sure
Candidate M 40 20 40
Candidate N 30 35 35
389. The table above shows the results of a survey of
100voters who each responded “Favorable” or
“Unfavorable” or “Not Sure” when asked about their
impressions of Candidate M and of Candidate N. What
was the number of voters who responded “Favorable”
for both candidates?
(1) The number of voters who did not respond
“Favorable” for either candidate was 40.
(2) The number of voters who responded
“Unfavorable” for both candidates was 10.
Arithmetic Sets
If x is the number of voters who responded
“Favorable” for both candidates, then it follows
from the table that the number of voters who
responded “Favorable” to at least one candidate
is 40 + 30 – x = 70 – x . is is because 40 + 30
represents the number of voters who responded
“Favorable” for Candidate M added to the
number of voters who responded “Favorable” for
Candidate N, a calculation that counts twice each
of the x voters who responded “Favorable” for
both candidates.
(1) Given that there were 40 voters who did not
respond “Favorable” for either candidate and
there were 100 voters surveyed, the number
of voters who responded “Favorable” to
at least one candidate is 100−40 = 60.
erefore, from the comments above, it
follows that 70− x = 60, and hence x = 10;
SUFFICIENT.
(2) e information given a ects only the
numbers of voters in the categories
“Unfavorable” for Candidate M only,
“Unfavorable” for Candidate N only, and
“Unfavorable” for both candidates. us,
the numbers of voters in the categories
“Favorable” for Candidate M only,
“Favorable” for Candidate N only, and
“Favorable” for both candidates are not
a ected. Since these latter categories are
only constrained to have certain integer
values that have a total sum of 70− x , more
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348
than one possibility exists for the value of x .
For example, the numbers of voters in the
categories “Favorable” for Candidate M
only, “Favorable” for Candidate N only,
and “Favorable” for both candidates could
be 25, 15, and 15, respectively, which gives
70 – x =25 + 15 + 15, or x = 15. However,
the numbers of voters in the categories
“Favorable” for Candidate M only,
“Favorable” for Candidate N only, and
“Favorable” for both candidates could be
30, 20, and 10, respectively, which gives
70− x = 30 + 20 + 10, or x = 10; NOT
su cient.
e correct answer is A;
statement 1 alone is su cient.
390. A school administrator will assign each student in a group
of n students to one of m classrooms. If 3 < m < 13 < n ,
is it possible to assign each of the n students to one
of the m classrooms so that each classroom has the
same number of students assigned to it?
(1) It is possible to assign each of 3 n students
to one of m classrooms so that each
classroom has the same number of students
assigned to it.
(2) It is possible to assign each of 13 n students
to one of m classrooms so that each
classroom has the same number of students
assigned to it.
Arithmetic Properties of numbers
Determine if n is divisible by m .
(1) Given that 3 n is divisible by m , then n is
divisible by m if m = 9 and n = 27 (note that
3 < m < 13 < n , 3 n = 81, and m = 9, so 3 n is
divisible by m ) and n is not divisible by m if
m = 9 and n = 30 (note that 3 < m < 13 < n ,
3 n = 90, and m = 9, so 3 n is divisible by m );
NOT su cient.
(2) Given that 13 n is divisible by m , then
13 n = qm , or =
n
m
q
13, for some integer q .
Since 13 is a prime number that divides
qm (because 13 n = qm ) and 13 does not
divide m (because m <13), it follows that 13
divides q .
erefore, q
13 is an integer, and since
=
n
m
q
13, then n
m is an integer. us, n is divisible
by m ; SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
391. If q, s, and t are all different numbers, is q < s < t ?
(1) t−q = |t−s| + |s−q|
(2) t > q
Algebra Absolute value
(1) It is given that t−q=|t−s|+|s−q|,
which can be rewritten without absolute
values in four mutually exclusive and
collectively exhaustive cases by making use
of the algebraic de nition of absolute value.
Recall that |x|=x if x>0, and |x|=–x if
x<0. us, for example, if t−s<0, then
|t−s|=–(t−s).
Case 1: t>s and s>q. In this case, t−s>0
and s−q>0, and so t−q=|t−s|+|s−q|
is equivalent to t−q=(t−s)+(s−q),
which is an identity. erefore, the case
for which t>s and s>q is consistent with
the given information and the assumption
t−q=|t−s|+|s−q|.
Case 2: t>s and s<q. In this case, t−s>0
and s−q<0, and so t−q=|t−s|+|s−q|
is equivalent to t−q=(t−s)−(s−q),
or s=q, which is not consistent with the
assumption that q, s, and t are all di erent
numbers. erefore, the case for which
t>s and s<q is not consistent with the
given information and the assumption
t−q=|t−s|+|s−q|.
Case 3: t<s and s>q. In this case, t−s<0
and s−q>0, and so t−q=|t−s|+|s−q|
is equivalent to t−q=–(t−s)+(s−q),
or t=s, which is not consistent with the
assumption that q, s, and t are all di erent
numbers. erefore, the case for which
t<s and s>q is not consistent with the
given information and the assumption
t−q=|t−s|+|s−q|.
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349
6.5 Data Suffi ciency Answer Explanations
Case 4: t<s and s<q. In this case, t−s<0
and s−q<0, and so t−q=|t−s|+|s−q|
is equivalent to t−q=–(t−s)−(s−q),
or t=q, which is not consistent with the
assumption that q, s, and t are all di erent
numbers. erefore, the case for which
t<s and s<q is not consistent with the
given information and the assumption
t−q=|t−s|+|s−q|. e only case that
is consistent with the given information
and the assumption t−q=|t−s|+|s−q|
is Case 1. erefore, it follows that t>s
and s>q, and this implies q<s<t;
SUFFICIENT.
(2) Given that t>q, it is possible that q<s<t
is true (for example, when s is between t and
q) and it is possible that q<s<t is false (for
example, when s is greater than t); NOT
su cient.
e correct answer is A;
statement 1 alone is su cient.
392. What is the median number of employees assigned
per project for the projects at Company Z ?
(1) 25 percent of the projects at Company Z have 4
or more employees assigned to each project.
(2) 35 percent of the projects at Company Z have 2
or fewer employees assigned to each project.
Arithmetic Statistics
(1) Although 25 percent of the projects have 4
or more employees, there is essentially no
information about the middle values of
the numbers of employees per project. For
example, if there were a total of 100 projects,
then the median could be 2 (75 projects
that have exactly 2 employees each and
25 projects that have exactly 4employees
each) or the median could be 3 (75 projects
that have exactly 3 employees each and
25 projects that have exactly 4 employees
each); NOT su cient.
(2) Although 35 percent of the projects have 2
or fewer employees, there is essentially no
information about the middle values of
the numbers of employees per project. For
example, if there were a total of 100 projects,
then the median could be 3 (35 projects
that have exactly 2 employees each and
65 projects that have exactly 3employees
each) or the median could be 4 (35 projects
that have exactly 2 employees each and
65 projects that have exactly 4 employees
each); NOT su cient.
Given both (1) and (2), 100−(25+35) percent =
40percent of the projects have exactly
3employees. erefore, when the numbers of
employees per project are listed from least to
greatest, 35 percent of the numbers are 2 or less
and (35+40)percent=75 percent are 3 or less,
and hence the median is 3.
e correct answer is C;
both statements together are su cient.
393. Last year, a certain company began manufacturing
product X and sold every unit of product X that it
produced. Last year the company’s total expenses
for manufacturing product X were equal to $100,000
plus 5percent of the company’s total revenue from all
units of product X sold. If the company made a pro t
on productX last year, did the company sell more than
21,000 units of product X last year?
(1) The company’s total revenue from the sale of
product X last year was greater than $110,000.
(2) For each unit of product X sold last year, the
company’s revenue was $5.
Algebra Applied problems
For a company that made a pro t last year
from selling product X and had total expenses
for product X of $100,000 + 0.05 R , where
R is the total revenue for selling product X,
determine whether the company sold more than
21,000units of product X last year.
Note that since the company made a pro t,
revenue−cost, which is given by
R −($100,000 + 0.05 R ) = 0.95 R −$100,000,
must be positive.
(1) It is given that R > $110,000. It is possible
to vary the unit price and the number of
units sold so that R > $110,000 and more
than 21,000 units were sold, and also so that
R > $110,000 and less than 21,000 units
were sold. For example, if 25,000 units
were sold for $10 per unit, then
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350
R = 25,000($10) = $250,000 > $110,000
and 25,000 > 21,000. On the other hand, if
20,000 units were sold for $10 per unit, then
R = 20,000($10) = $200,000 > $110,000
and 20,000 < 21,000; NOT su cient.
(2) It is given that the company’s revenue for
each unit of product X was $5. If the
company manufactured and sold x units
of product X, then its revenue was $5 x .
Because the company made a pro t,
0.95($5 x )−$100,000 > 0, and so
0.95($5 x )−$100,000 >0
$4.75 x −$100,000 >0
$4.75 x >$100,000
x >21,052; SUFFICIENT.
To avoid long division in the last step, note
that 4.75(21,000) = 99,750, and thus from
4.75 x > 100,000, it follows that x > 21,000.
e correct answer is B;
statement 2 alone is su cient.
394. Beginning in January of last year, Carl made deposits
of $120 into his account on the 15th of each month
for several consecutive months and then made
withdrawals of $50 from the account on the 15th of
each of the remaining months of last year. There were
no other transactions in the account last year. If the
closing balance of Carl’s account for May of last year
was $2,600, what was the range of the monthly
closing balances of Carl’s account last year?
(1) Last year the closing balance of Carl’s account
for April was less than $2,625.
(2) Last year the closing balance of Carl’s account
for June was less than $2,675.
Arithmetic Statistics
(1) If Carl began making $50 withdrawals on
or before May 15, his account balance on
April 16 would be at least $50 greater than
it was on the last day of May. us, his account
balance on April 16 would be at least
$2,600+$50=$2,650, which is contrary to
the information given in (1). erefore,
Carl did not begin making $50 withdrawals
until June 15 or later. ese observations can
be used to give at least two possible ranges.
Carl could have had an account balance of
$2,000 on January 1, made $120 deposits in
each of the rst 11months of the year, and
then made a $50 withdrawal on December 15,
which gives a range of monthly closing
balances of (120)(10). Also, Carl could
have had an account balance of $2,000 on
January 1, made $120deposits in each of
the rst 10 months of the year, and then
made $50 withdrawals on November 15
and on December 15, which gives a range
of monthly closing balances of (120)(9);
NOT su cient.
(2) On June 1, Carl’s account balance was the
same as its closing balance was for May,
namely $2,600. Depending on whether Carl
made a $120 deposit or a $50withdrawal
on June 15, Carl’s account balance on June 16
was either $2,720 or $2,550. It follows from
the information given in (2) that Carl’s
balance on June 16 was $2,550. erefore,
Carl began making $50 withdrawals on or
before June 15. ese observations can be
used to give at least two possible ranges.
Carl could have had an account balance of
$2,680 on January1, made one $120 deposit
on January 15, and then made a $50
withdrawal in each of the remaining
11months of the year (this gives a closing
balance of $2,600 for May), which gives
a range of monthly closing balances of
(50)(11). Also, Carl could have had an account
balance of $2,510 on January 1, made $120
deposits on January 15 and on February 15,
and then made a $50withdrawal in each of
the remaining 10 months of the year (this
gives a closing balance of $2,600 for May),
which gives a range of monthly closing
balances of (50)(10); NOT su cient.
Given both (1) and (2), it follows from the
remarks above that Carl began making $50
withdrawals on June 15. erefore, the changes
to Carl’s account balance for each month of last
year are known. Since the closing balance for
May is given, it follows that the closing balances
for each month of last year are known, and
hence the range of these 12 known values can be
determined.
e correct answer is C;
both statements together are su cient.
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6.5 Data Suffi ciency Answer Explanations
395. Are all of the numbers in a certain list of 15 numbers
equal?
(1) The sum of all the numbers in the list is 60.
(2) The sum of any 3 numbers in the list is 12.
Arithmetic Properties of numbers
(1) If there are 15 occurrences of the number 4
in the list, then the sum of the numbers in
the list is 60 and all the numbers in the list
are equal. If there are 13 occurrences of the
number 4 in the list, 1 occurrence of the
number 3 in the list, and 1 occurrence of
the number 5 in the list, then the sum of the
numbers in the list is 60 and not all the
numbers in the list are equal; NOT
su cient.
(2) Given that the sum of any 3 numbers in the
list is 12, arrange the numbers in the list in
numerical order, from least to greatest:
a
1 ≤ a
2 ≤ a
3 ≤ . . . ≤ a
15 .
If a
1 < 4, then a
1 + a
2 + a
3 < 4 + a
2 + a
3 .
erefore, from (2), 12 < 4 + a
2 + a
3 , or
8< a
2 + a
3 , and so at least one of the values
a
2 and a
3 must be greater than 4. Because
a
2 ≤ a
3 , it follows that a
3 > 4. Since the
numbers are arranged from least to greatest,
it follows that a
4 > 4 and a
5 > 4. But then,
a
3 + a
4 + a
5 > 4 + 4 + 4= 12, contrary to (2),
and so a
1 < 4 is not true. erefore, a
1 ≥ 4.
Since a
1 is the least of the 15 numbers,
a
n ≥ 4 for n = 1, 2, 3, …, 15.
If a
15 > 4, then a
13 + a
14 + a
15 > a
13 + a
14 + 4.
erefore, from (2), 12> a
13 + a
14 +4, or
8> a
13 + a
14 , and so at least one of the values
a
13 and a
14 must be less than 4. Because
a
13 ≤ a
14 , it follows that a
13 < 4. Since the
numbers are arranged from least to greatest,
it follows that a
11 < 4 and a
12 < 4. But then
a
11 + a
12 + a
13 < 4 + 4 + 4= 12, contrary
to (2). erefore, a
15 ≤ 4. Since a
15 is the
greatest of the 15numbers, a
n ≤ 4
for n = 1, 2, 3, …, 15.
It has been shown that, for n =1, 2, 3, …, 15,
each of a
n ≥ 4 and a
n ≤ 4 is true. erefore,
a
n = 4 for n =1, 2, 3, …, 15; SUFFICIENT.
e correct answer is B;
statement 2 alone is su cient.
396. If the average (arithmetic mean) of six numbers is 75,
how many of the numbers are equal to 75 ?
(1) None of the six numbers is less than 75.
(2) None of the six numbers is greater than 75.
Arithmetic Statistics
If the average of six numbers is 75, then
1
6 of the sum of the numbers is 75. erefore,
the sum of the numbers is (6)(75).
(1) If one of the numbers is greater than 75,
then we can write that number as 75+ x
for some positive number x . Consequently,
the sum of the 6numbers must be at least
(5)(75) + (75 + x ) = (6)(75) + x , which is
greater than (6)(75), contrary to the fact
that the sum is equal to (6)(75). Hence,
none of the numbers can be greater than 75.
Since none of the numbers can be less than 75
(given information) and none of the
numbers can be greater than 75, it follows
that each of the numbers is equal to 75;
SUFFICIENT.
(2) If one of the numbers is less than 75, then
we can write that number as 75− x for some
positive number x . Consequently, the sum
of the 6numbers must be at most (5)(75) +
(75− x ) = (6)(75)− x , which is less than
(6)(75), contrary to the fact that the sum
is equal to (6)(75). Hence, none of the
numbers can be less than 75. Since none of
the numbers can be less than 75 and none
of the numbers can be greater than 75
(given information), it follows that each of
the numbers is equal to 75; SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
397. What amount did Jean earn from the commission on
her sales in the rst half of 1988 ?
(1) In 1988 Jean’s commission was 5 percent of the
total amount of her sales.
(2) The amount of Jean’s sales in the second half of
1988 averaged $10,000 per month more than in
the rst half.
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352
Arithmetic Applied problems
Let A be the amount of Jean’s sales in the rst
half of 1988. Determine the value of A .
(1) If the amount of Jean’s sales in the rst half
of 1988 was $10,000, then her commission
in the rst half of 1988 would have been
(5%)($10,000)=$500. On the other hand,
if the amount of Jean’s sales in the rst half
of 1988 was $100,000, then her commission
in the rst half of 1988 would have been
(5%)($100,000)=$5,000; NOT su cient.
(2) No information is given that relates the
amount of Jean’s sales to the amount of
Jean’s commission; NOT su cient.
Given (1) and (2), from (1) the amount of Jean’s
commission in the rst half of 1988 is (5%) A .
From (2) the amount of Jean’s sales in the second
half of 1988 is A +$60,000. Both statements
together do not give information to determine
the value of A .
e correct answer is E;
both statements together are still not su cient.
A
DB
C
398. In the gure above, if the area of triangular region D
is 4, what is the length of a side of square region A ?
(1) The area of square region B is 9.
(2) The area of square region C is 64
9.
Geometry Area
e area of the triangular region D can be
represented by bh
1
2, where b is the base of the
triangle (and is equal to the length of a side of
the square region C ) and h is the height of the
triangle (and is equal to the length of a side of
the square region B ). e area of any square is
equal to the length of a side squared. e
Pythagorean theorem is used to nd the length
of a side of a right triangle, when the length of
the other 2 sides of the triangle are known and is
represented by a
2 + b
2 = c
2 , where a and b are the
lengths of the 2 perpendicular sides of the triangle
and c is the length of the hypotenuse.
Although completed calculations are provided
in what follows, keep in mind that completed
calculations are not needed to solve this problem.
(1) If the area of B is 9, then the length of each
side is 3. erefore, h = 3. en, b can be
determined, since the area of the triangle is,
by substitution, =b41
2(3 ) or 8=3 b or =b
8
3.
Once b is known, the Pythagorean theorem
can be used: ⎛
⎝⎞
⎠+=c
8
33
2
22
or +=c
64
992
or =c
145
9
2. e length of a side of A is thus
145
9; SUFFICIENT.
(2) If the area of C is 64
9, then the length of
each side is 8
3. erefore, b =8
3. e area
of a triangle is A =1
2 bh so =⎛
⎝⎞
⎠
h41
2
8
3,
=h88
3, and 3= h . Once h is known, the
Pythagorean theorem can be used as above;
SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
399. If n is a positive integer and k = 5.1 × 10
n , what is the
value of k ?
(1) 6,000 < k < 500,000
(2) k
2 = 2.601 × 10
9
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6.5 Data Suffi ciency Answer Explanations
Arithmetic Properties of numbers
Given that k = 5.1 × 10
n , where n is a positive
integer, then the value of k must follow the
pattern shown in the following table:
n k
151
2 510
3 5,100
4 51,000
5 510,000
6 5,100,000
..
..
..
(1) Given that 6,000 < k < 500,000, then k
must have the value 51,000, and so n = 4;
SUFFICIENT.
(2) Given that k
2 = 2.601 × 10
9 , then
k2.601 10 2,601 10 2,601 10
96 6
=×=×=×
51 10 51,000
3
=× = , and so n = 4;
SUFFICIENT.
e correct answer is D;
each statement alone is su cient.
x˚
w˚
y˚
z˚
400. What is the value of x + y in the gure above?
(1) w = 95
(2) z = 125
Geometry Angles
x°
w°a°
d°c°
b°
y°
z°
In the gure above, a , b , c , and d are the
degree measures of the interior angles of the
quadrilateral formed by the four lines and
a + b + c + d =360. en
+++
=−+−+−+−
=−+++
=−
=
wxyz
adcb
abcd
(180 ) (180 ) (180 ) (180 )
720 ( )
720 360
360.
Determine the value of x + y .
(1) Given that w = 95, then 95+ x + y + z =360
and x + y + z = 265. If z =65, for example,
then x + y =200. On the other hand,
if z =100, then x + y = 165; NOT su cient.
(2) Given that z =125, then w + x + y + 125 =
360 and w + x + y =235. If w = 35, for
example, then x + y =200. On the other
hand, if w = 100, then x + y = 135; NOT
su cient.
Taking (1) and (2) together, 95 + x + y + 125 = 360,
and so x + y =140.
e correct answer is C;
both statements together are su cient.
401. If n and k are positive integers, is +>nk n2 ?
(1) k >3 n
(2) n + k >3 n
Algebra Inequalities
Determine if +>nk n2. Since each side
is positive, squaring each side preserves the
inequality, so +>nk n2 is equivalent to
++>nk nk n n()()(2)(2)
, which in turn is
equivalent to n + k >4 n , or to k >3 n .
(1) Given that k >3 n , then +>nk n2;
SUFFICIENT.
(2) Given that n + k > 3 n , then k > 2 n . However,
it is possible for k > 2 n to be true and k >3 n
to be false (for example, k = 3 and n = 1) and
it is possible for k > 2 n to be true and k > 3 n
to be true (for example, k = 4 and n = 1);
NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
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354
402. In a certain business, production index p is directly
proportional to ef ciency index e , which is in turn
directly proportional to investment index i . What is p if
i = 70 ?
(1) e = 0.5 whenever i = 60.
(2) p = 2.0 whenever i = 50.
Arithmetic Proportions
(1) is gives only values for e and i , and, while
p is directly proportional to e , the nature
of this proportion is unknown. erefore,
p cannot be determined; NOT su cient.
(2) Since p is directly proportional to e , which is
directly proportional to i , then p is directly
proportional to i . erefore, the following
proportion can be set up: p
i=2.0
50 . If i = 70,
then =
p
70
2.0
50 . rough cross multiplying,
this equation yields 50 p = 140, or p = 2.8;
SUFFICIENT.
e preceding approach is one method that can
be used. Another approach is as follows: It is
given that p = Ke = K ( Li ) = ( KL ) i , where K and L
are the proportionality constants, and the value of
70 KL is to be determined. Statement (1) allows
us to determine the value of L , but gives nothing
about K , and thus (1) is not su cient. Statement
(2) allows us to determine the value of KL , and
thus (2) is su cient.
e correct answer is B;
statement 2 alone is su cient.
403. If n is a positive integer, what is the tens digit of n ?
(1) The hundreds digit of 10 n is 6.
(2) The tens digit of n + 1 is 7.
Arithmetic Properties of numbers
(1) Given that the hundreds digit of 10 n is 6,
the tens digit of n is 6, since the hundreds
digit of 10 n is always equal to the tens digit
of n ; SUFFICIENT.
(2) Given that the tens digit of n + 1 is 7, it
is possible that the tens digit of n is 7 (for
example, n = 70) and it is possible that the
tens digit of n is 6 (for example, n = 69);
NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
404. What is the value of +−
−
ttx
tx
2?
(1)
−=
t
tx
23
(2) t − x = 5
Algebra Simplifying algebraic expressions
Determine the value of +−
−
ttx
tx
2.
(1) Since −=
t
tx
2 3 and
+−
−=−+−
−=−+
ttx
tx
t
tx
tx
tx
t
tx
22 2
1,
it follows that +−
−=+
ttx
tx
231
;
SUFFICIENT.
(2) Given that t − x = 5, it follows that
+−
−=+=+
ttx
tx
tt
225
5
2
51, which can
vary when the value of t varies. For example,
+=t
2
513
if t = 5 (choose x = 0 to have
t − x = 5) and +=t
2
515
if t =10 (choose
x =5 to have t − x =5); NOT su cient.
e correct answer is A;
statement 1 alone is su cient.
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7.0 Reading Comprehension
357
7.0 Reading Comprehension
Reading comprehension questions appear in the Verbal section of the GMAT
® exam. e Verbal
section uses multiple‐choice questions to measure your ability to read and comprehend written material,
to reason and evaluate arguments, and to correct written material to conform to standard written
English. Because the Verbal section includes content from a variety of topics, you may be generally
familiar with some of the material; however, neither the passages nor the questions assume knowledge
of the topics discussed. Reading comprehension questions are intermingled with critical reasoning and
sentence correction questions throughout the Verbal section of the test.
You will have 75 minutes to complete the Verbal section, or an average of about 1¾ minutes to answer
each question. Keep in mind you will need time to read the written passages—and that time is not
factored into the 1¾ minute average. erefore, you should plan to proceed more quickly through the
reading comprehension questions in order to give yourself enough time to read the passages thoroughly.
Reading comprehension questions begin with written passages up to 350 words long. e passages
discuss topics from the social sciences, humanities, the physical or biological sciences, and such
business‐related fields as marketing, economics, and human resource management. e passages are
accompanied by questions that will ask you to interpret the passage, apply the information you gather
from the reading, and make inferences (or informed assumptions) based on the reading. For these
questions, you will see a split computer screen. e written passage will remain visible on the left side
as each question associated with that passage appears, in turn, on the right side. You will see only one
question at a time. However, the number of questions associated with each passage may vary.
As you move through the reading comprehension sample questions, try to determine a process that
works best for you. You might begin by reading a passage carefully and thoroughly. Some test‐takers
prefer to skim the passages the first time through, or even to read the first question before reading the
passage. You may want to reread any sentences that present complicated ideas or introduce terms that
are new to you. Read each question and series of answers carefully. Make sure you understand exactly
what the question is asking and what the answer choices are.
If you need to, you may go back to the passage and read any parts that are relevant to answering the
question. Specific portions of the passages may be indicated in the related questions.
e following pages describe what reading comprehension questions are designed to measure, present
the directions that will precede questions of this type, and describe the various question types. is
chapter also provides test‐taking strategies, sample questions, and detailed explanations of all the
questions. e explanations further illustrate the ways in which reading comprehension questions
evaluate basic reading skills.
7.0 Reading Comprehension Verbal Questions
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7.1 What Is Measured
Reading comprehension questions measure your ability to understand, analyze, and apply information
and concepts presented in written form. All questions are to be answered on the basis of what is stated
or implied in the reading material, and no specific prior knowledge of the material is required.
e GMAT reading comprehension questions evaluate your ability to do the following:
• Understand words and statements.
Although the questions do not test your vocabulary (they will not ask you to define terms), they
do test your ability to interpret special meanings of terms as they are used in the reading passages.
e questions will also test your understanding of the English language. ese questions may ask
about the overall meaning of a passage.
• Understand logical relationships between points and concepts.
is type of question may ask you to determine the strong and weak points of an argument or
evaluate the relative importance of arguments and ideas in a passage.
• Draw inferences from facts and statements.
e inference questions will ask you to consider factual statements or information presented in a
reading passage and reach conclusions on the basis of that information.
• Understand and follow the development of quantitative concepts as they are presented in
written material.
is may involve the interpretation of numerical data or the use of simple arithmetic to reach
conclusions about material in a passage.
ere are six kinds of reading comprehension questions, each of which tests a di erent skill. e
reading comprehension questions ask about the following areas:
Main idea
Each passage is a unified whole—that is, the individual sentences and paragraphs support and develop
one main idea or central point. Sometimes you will be told the central point in the passage itself, and
sometimes it will be necessary for you to determine the central point from the overall organization or
development of the passage. You may be asked in this kind of question to
• recognize a correct restatement, or paraphrasing, of the main idea of a passage
• identify the author’s primary purpose or objective in writing the passage
• assign a title that summarizes, briefly and pointedly, the main idea developed in the passage
Supporting ideas
ese questions measure your ability to comprehend the supporting ideas in a passage and di erentiate
them from the main idea. e questions also measure your ability to di erentiate ideas that are explicitly
stated in a passage from ideas that are implied by the author but are not explicitly stated. You may be
asked about
• facts cited in a passage
• the specific content of arguments presented by the author in support of his or her views
• descriptive details used to support or elaborate on the main idea
359
Whereas questions about the main idea ask you to determine the meaning of a passage as a whole ,
questions about supporting ideas ask you to determine the meanings of individual sentences and
paragraphs that contribute to the meaning of the passage as a whole. In other words, these questions ask
for the main point of one small part of the passage.
Inferences
ese questions ask about ideas that are not explicitly stated in a passage but are implied by the author.
Unlike questions about supporting details, which ask about information that is directly stated in a
passage, inference questions ask about ideas or meanings that must be inferred from information that
is directly stated. Authors can make their points in indirect ways, suggesting ideas without actually
stating them. Inference questions measure your ability to understand an author’s intended meaning in
parts of a passage where the meaning is only suggested. ese questions do not ask about meanings
or implications that are remote from the passage; rather, they ask about meanings that are developed
indirectly or implications that are specifically suggested by the author.
To answer these questions, you may have to
• logically take statements made by the author one step beyond their literal meanings
• recognize an alternative interpretation of a statement made by the author
• identify the intended meaning of a word used figuratively in a passage
If a passage explicitly states an e ect, for example, you may be asked to infer its cause. If the author
compares two phenomena, you may be asked to infer the basis for the comparison. You may be asked
to infer the characteristics of an old policy from an explicit description of a new one. When you read a
passage, you should concentrate not only on the explicit meaning of the author’s words, but also on the
more subtle meaning implied by those words.
Applying information to a context outside the passage itself
ese questions measure your ability to discern the relationships between situations or ideas presented
by the author and other situations or ideas that might parallel those in the passage. In this kind of
question, you may be asked to
• identify a hypothetical situation that is comparable to a situation presented in the passage
• select an example that is similar to an example provided in the passage
• apply ideas given in the passage to a situation not mentioned by the author
• recognize ideas that the author would probably agree or disagree with on the basis of statements
made in the passage
Unlike inference questions, application questions use ideas or situations not taken from the passage.
Ideas and situations given in a question are like those given in the passage, and they parallel ideas and
situations in the passage; therefore, to answer the question, you must do more than recall what you read.
You must recognize the essential attributes of ideas and situations presented in the passage when they
appear in di erent words and in an entirely new context.
7.1 Reading Comprehension What Is Measured
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360
Logical structure
ese questions require you to analyze and evaluate the organization and logic of a passage. ey may
ask you
• how a passage is constructed—for instance, does it define, compare or contrast, present a new idea,
or refute an idea?
• how the author persuades readers to accept his or her assertions
• the reason behind the author’s use of any particular supporting detail
• to identify assumptions that the author is making
• to assess the strengths and weaknesses of the author’s arguments
• to recognize appropriate counterarguments
ese questions measure your ability not only to comprehend a passage but also to evaluate it critically.
However, it is important for you to realize that logical structure questions do not rely on any kind of
formal logic, nor do they require you to be familiar with specific terms of logic or argumentation. You
can answer these questions using only the information in the passage and careful reasoning.
About the style and tone
Style and tone questions ask about the expression of a passage and about the ideas in a passage that may
be expressed through its diction—the author’s choice of words. You may be asked to deduce the author’s
attitude to an idea, a fact, or a situation from the words that he or she uses to describe it. You may
also be asked to select a word that accurately describes the tone of a passage—for instance, “critical,”
“questioning,” “objective,” or “enthusiastic.”
To answer this type of question, you will have to consider the language of the passage as a whole. It
takes more than one pointed, critical word to make the tone of an entire passage “critical.” Sometimes,
style and tone questions ask what audience the passage was probably intended for or what type of
publication it probably appeared in. Style and tone questions may apply to one small part of the passage
or to the passage as a whole. To answer them, you must ask yourself what meanings are contained in
the words of a passage beyond the literal meanings. Did the author use certain words because of their
emotional content, or because a particular audience would expect to hear them? Remember, these
questions measure your ability to discern meaning expressed by the author through his or her choice
of words.
7.2 Test-Taking Strategies
1. Do not expect to be completely familiar with any of the material presented in reading
comprehension passages.
You may find some passages easier to understand than others, but all passages are designed to
present a challenge. If you have some familiarity with the material presented in a passage, do not let
this knowledge influence your choice of answers to the questions. Answer all questions on the basis
of what is stated or implied in the passage itself.
361
2. Analyze each passage carefully, because the questions require you to have a specific and detailed
understanding of the material.
You may nd it easier to do the analysis rst before moving to the questions. You may nd that
you prefer to skim the passage the first time and read more carefully once you understand what
a question asks. You may even want to read the question before reading the passage. You should
choose the method most suitable for you.
3. Focus on key words and phrases, and make every effort to avoid losing the sense of what is
discussed in the passage.
Keep the following in mind:
• Note how each fact relates to an idea or an argument.
• Note where the passage moves from one idea to the next.
• Separate main ideas from supporting ideas.
• Determine what conclusions are reached and why.
4. Read the questions carefully, making certain that you understand what is asked.
An answer choice that accurately restates information in the passage may be incorrect if it does not
answer the question. If you need to, refer back to the passage for clarification.
5. Read all the choices carefully.
Never assume that you have selected the best answer without first reading all the choices.
6. Select the choice that answers the question best in terms of the information given in the passage.
Do not rely on outside knowledge of the material to help you answer the questions.
7. Remember that comprehension—not speed—is the critical success factor when it comes to reading
comprehension questions.
7.3 The Directions
ese are the directions that you will see for reading comprehension questions when you take the
GMAT exam. If you read them carefully and understand them clearly before going to sit forthe test,
you will not need to spend too much time reviewing them once you are at the test center and the test is
under way.
e questions in this group are based on the content of a passage. After reading the passage, choose the
best answer to each question. Answer all questions following the passage on the basis of what is stated or
implied in the passage .
7.2 Reading Comprehension Test-Taking Strategies
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7.4 Practice Questions
Each of the reading comprehension questions is based on the content of a passage. After reading the
passage answer all questions pertaining to it on the basis of what is stated or implied in the passage.
Foreach question, select the best answer of the choices given.
Line
(5)
(10)
(15)
(20)
(25)
(30)
(35)
Biologists have advanced two theories to explain
why schooling of sh occurs in so many sh species.
Because schooling is particularly widespread among
species of small sh, both theories assume that
schooling offers the advantage of some protection
from predators.
Proponents of theory A dispute the assumption
that a school of thousands of sh is highly visible.
Experiments have shown that any sh can be seen,
even in very clear water, only within a sphere of 200
meters in diameter. When sh are in a compact group,
the spheres of visibility overlap. Thus the chance of
a predator nding the school isonly slightly greater
than the chance of the predator nding a single sh
swimming alone. Schooling is advantageous to the
individual sh because a predator’s chance of nding
any particular sh swimming in the school is much
smaller than its chance of nding at least one of
the same group of sh if the sh were dispersed
throughout an area.
However, critics of theory A point out that some
sh form schools even in areas where predators
are abundant and thus little possibility of escaping
detection exists. They argue that the school continues
to be of value to its members even after detection.
They advocate theory B, the “confusion effect,” which
can be explained in two different ways.
Sometimes, proponents argue, predators simply
cannot decide which sh to attack. This indecision
supposedly results from a predator’s preference
for striking prey that is distinct from the rest of the
school in appearance. In many schools the sh are
almost identical in appearance, making it dif cult for a
predator to select one. The second explanation for
the “confusion effect” has to do with the sensory
confusion caused by a large number of prey moving
around the predator. Even if the predator
(40)
makes the decision to attack a particular sh,
themovement of other prey in the school can
bedistracting. The predator’s dif culty can
be compared to that of a tennis player trying
to hitatennis ball when two are approaching
simultaneously.
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363
Questions 405–408 refer to the passage.
405. According to the passage, theory B states that which
of the following is a factor that enables a schooling sh
to escape predators?
(A) The tendency of sh to form compact groups
(B) The movement of other sh within the school
(C) The inability of predators to detect schools
(D) The ability of sh to hide behind one another in a
school
(E) The great speed with which a school can
disperse
406. According to the passage, both theory A and theory B
have been developed to explain how
(A) sh hide from predators by forming schools
(B) forming schools functions to protect sh from
predators
(C) schooling among sh differs from other
protective behaviors
(D) small sh are able to make rapid decisions
(E) small sh are able to survive in an environment
densely populated by large predators
407. According to one explanation of the “confusion
effect,” a sh that swims in a school will have greater
advantages for survival if it
(A) tends to be visible for no more than 200 meters
(B) stays near either the front or the rear of a school
(C) is part of a small school rather than a large
school
(D) is very similar in appearance to the other sh in
the school
(E) is medium‐sized
408. The author is primarily concerned with
(A) discussing different theories
(B) analyzing different techniques
(C) defending two hypotheses
(D) refuting established beliefs
(E) revealing new evidence
7.4 Reading Comprehension Practice Questions
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364
Line
(5)
(10)
(15)
(20)
(25)
Scientists long believed that two nerve clusters in
the human hypothalamus, called suprachiasmatic
nuclei (SCNs), were what controlled our circadian
rhythms. Those rhythms are the biological cycles
that recur approximately every 24 hours in
synchronization with the cycle of sunlight and
darkness caused by Earth’s rotation. Studies have
demonstrated that in some animals, the SCNs
control daily uctuations in blood pressure, body
temperature, activity level, and alertness, as well as
the nighttime release of the sleep‐promoting agent
melatonin. Furthermore, cells in the human retina
dedicated to transmitting information about light
levels to the SCNs have recently been discovered.
Four critical genes governing circadian cycles
have been found to be active in every tissue,
however, not just the SCNs, of ies, mice, and
humans. In addition, when laboratory rats that
usually ate at will were fed only once a day, peak
activity of a clock gene in their livers shifted by
12hours, whereas the same clock gene in the
SCNs remained synchronized with light cycles. While
scientists do not dispute the role of the SCNs in
controlling core functions such as the regulation of
body temperature and blood pressure, scientists
now believe that circadian clocks in other organs
and tissues may respond to external cues other than
light—including temperature changes—that recur
regularly every 24 hours.
Questions 409–411 refer to the passage.
409. The primary purpose of the passage is to
(A) challenge recent ndings that appear to
contradict earlier ndings
(B) present two sides of an ongoing scienti c debate
(C) report answers to several questions that have
long puzzled researchers
(D) discuss evidence that has caused a long‐
standing belief to be revised
(E) attempt to explain a commonly misunderstood
biological phenomenon
410. The passage mentions each of the following as a
function regulated by the SCNs in some animals
EXCEPT
(A) activity level
(B) blood pressure
(C) alertness
(D) vision
(E) temperature
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365
411. The author of the passage would probably agree with
which of the following statements about the SCNs?
(A) The SCNs are found in other organs and tissues
of the body besides the hypothalamus.
(B) The SCNs play a critical but not exclusive role in
regulating circadian rhythms.
(C) The SCNs control clock genes in a number of
tissues and organs throughout the body.
(D) The SCNs are a less signi cant factor in
regulating blood pressure than scientists once
believed.
(E) The SCNs are less strongly affected by changes
in light levels than they are by other external
cues.
7.4 Reading Comprehension Practice Questions
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Line
(5)
(10)
(15)
(20)
(25)
In their study of whether offering a guarantee of
service quality will encourage customers to visit a
particular restaurant, Tucci and Talaga have found
that the effect of such guarantees is mixed. For
higher-priced restaurants, there is some evidence
that offering a guarantee increases the likelihood of
customer selection, probably re ecting the greater
nancial commitment involved in choosing an
expensive restaurant. For lower-priced restaurants,
where one expects less assiduous service, Tucci and
Talaga found that a guarantee could actually have a
negative effect: a potential customer might think that
a restaurant offering a guarantee is worried about
its service. Moreover, since customers understand a
restaurant’s product and know what to anticipate in
terms of service, they are empowered to question its
quality. This is not generally true in the case of skilled
activities such as electrical work, where, consequently,
a guarantee might have greater customer appeal.
For restaurants generally, the main bene t of
a service guarantee probably lies not so much in
customer appeal as in managing and motivating staff.
Staff members would know what service standards
are expected of them and also know that the success
of the business relies on their adhering to those
standards. Additionally, guarantees provide some
basis for de ning the skills needed for successful
service in areas traditionally regarded as unskilled,
such as waiting tables.
Questions 412–414 refer to the passage.
412. The primary purpose of the passage is to
(A) question the results of a study that examined
the effect of service-quality guarantees in the
restaurant industry
(B) discuss potential advantages and disadvantages
of service-quality guarantees in the restaurant
industry
(C) examine the conventional wisdom regarding
the effect of service-quality guarantees in the
restaurant industry
(D) argue that only certain restaurants would bene t
from the implementation of service-quality
guarantees
(E) consider the impact that service-quality
guarantees can have on the service provided by
a restaurant
413. It can be inferred that the author of the passage would
agree with which of the following statements about the
appeal of service guarantees to customers?
(A) Such guarantees are likely to be somewhat more
appealing to customers of restaurants than to
customers of other businesses.
(B) Such guarantees are likely to be more appealing
to customers who know what to anticipate in
terms of service.
(C) Such guarantees are likely to have less appeal in
situations where customers are knowledgeable
about a business’s product or service.
(D) In situations where a high level of nancial
commitment is involved, a service guarantee is
not likely to be very appealing.
(E) In situations where customers expect a high
level of customer service, a service guarantee is
likely to make customers think that a business is
worried about its service.
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367
414. According to the passage, Tucci and Talaga found
that service guarantees, when offered by lower-priced
restaurants, can have which of the following effects?
(A) Customers’ developing unreasonably high
expectations regarding service
(B) Customers’ avoiding such restaurants because
they fear that the service guarantee may not be
fully honored
(C) Customers’ interpreting the service guarantee as
a sign that management is not con dent about
the quality of its service
(D) A restaurant’s becoming concerned that its
service will not be assiduous enough to satisfy
customers
(E) A restaurant’s becoming concerned that
customers will be more emboldened to question
the quality of the service they receive
7.4 Reading Comprehension Practice Questions
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Line
(5)
(10)
(15)
(20)
(25)
(30)
The argument for “monetizing”—or putting a
monetary value on—ecosystem functions may be
stated thus: Concern about the depletion of natural
resources is widespread, but this concern, in the
absence of an economic argument for conservation,
has not translated into signi cant conservational
progress. Some critics blame this impasse on
environmentalists, whom they believe fail to address
the economic issues of environmental degradation.
Conservation can appear unpro table when compared
with the economic returns derived from converting
natural assets (pristine coastlines, for example) into
explicitly commercial ones (such as resort hotels).
But according to David Pearce, that illusion stems
from the fact that “services” provided by ecological
systems are not traded on the commodities market,
and thus have no readily quanti able value. To
remedy this, says Pearce, one has to show that all
ecosystems have economic value—indeed, that all
ecological services are economic services. Tourists
visiting wildlife preserves, for example, create
jobs and generate income for national economies;
undisturbed forests and wetlands regulate water
runoff and act as water-purifying systems, saving
millions of dollars worth of damage to property
and to marine ecosystems. In Gretchen Daily’s
view, monetization, while unpopular with many
environmentalists, re ects the dominant role that
economic considerations play in human behavior,
and the expression of economic value in a common
currency helps inform environmental decision-making
processes.
Questions 415–418 refer to the passage.
415. Information in the passage suggests that David Pearce
would most readily endorse which of the following
statements concerning monetization?
(A) Monetization represents a strategy that is
attractive to both environmentalists and their
critics.
(B) Monetization is an untested strategy,
but it is increasingly being embraced by
environmentalists.
(C) Monetization should at present be restricted to
ecological services and should only gradually
be extended to such commercial endeavors as
tourism and recreation.
(D) Monetization can serve as a means of
representing persuasively the value of
environmental conservation.
(E) Monetization should inform environmental
decision-making processes only if it is accepted
by environmentalist groups.
416. Which of the following most clearly represents an
example of an “ecological service” as that term is used
in line 20 ?
(A) A resort hotel located in an area noted for its
natural beauty
(B) A water-purifying plant that supplements natural
processes with nontoxic chemicals
(C) A wildlife preserve that draws many international
travelers
(D) A nonpro t rm that specializes in restoring
previously damaged ecosystems
(E) A newsletter that keeps readers informed of
ecological victories and setbacks
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369
417. According to the passage, Daily sees monetization as
an indication of which of the following?
(A) The centrality of economic interests to people’s
actions
(B) The reluctance of the critics of environmentalism
to acknowledge the importance of conservation
(C) The inability of nancial interests and ecological
interests to reach a common ideological ground
(D) The inevitability of environmental degradation
(E) The inevitability of the growth of ecological
services in the future
418. Which of the following can be inferred from the
passage concerning the environmentalists mentioned
in line 8 ?
(A) They are organized in opposition to the
generation of income produced by the sale of
ecological services.
(B) They are fewer in number but better organized
and better connected to the media than their
opponents.
(C) They have sometimes been charged with failing
to use a particular strategy in their pursuit of
conservational goals.
(D) They have been in the forefront of publicizing the
extent of worldwide environmental degradation.
(E) They de ne environmental progress differently
and more conservatively than do other organized
groups of environmentalists.
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
370
Line
(5)
(10)
(15)
(20)
(25)
(30)
Much research has been devoted to investigating
what motivates consumers to try new products.
Previous consumer research suggests that both the
price of a new product and the way it is advertised
affect consumers’ perceptions of the product’s
performance risk (the possibility that the product will
not function as consumers expect and/or will not
provide the desired bene ts). Some of this research
has concluded that a relatively high price will reduce
a consumer’s perception of the performance risk
associated with purchasing a particular product,
while other studies have reported that price has little
or no effect on perceived performance risk. These
con icting ndings may simply be due to the nature
of product advertisements: a recent study indicates
that the presentation of an advertised message has a
marked effect on the relationship between price and
perceived performance risk.
Researchers have identi ed consumers’ perception
of the credibility of the source of an advertised
message—i.e., the manufacturer—as another factor
affecting perceived performance risk: one study
found that the greater the source credibility, the lower
the consumer’s perception of the risk of purchasing
an advertised new product. However, past research
suggests that the relationship between source
credibility and perceived performance risk may be
more complex: source credibility may interact with
price in a subtle way to affect consumers’ judgments
of the performance risk associated with an advertised
product.
Questions 419–422 refer to the passage.
419. According to the passage, the studies referred to in
line 12 reported which of the following about the effect
of price on consumers’ perception of the performance
risk associated with a new product?
(A) Although most consumers regard price as
an important factor, their perception of the
performance risk associated with a new product
is ultimately determined by the manufacturer’s
reputation.
(B) Price interacts with the presentation of an
advertised message to affect perceived
performance risk.
(C) Price does not signi cantly affect consumers’
perception of the performance risk associated
with a new product.
(D) Consumers tend to regard price as more important
than the manufacturer’s credibility when they are
buying from that manufacturer for the rst time.
(E) Consumers are generally less concerned about
a new product’s performance risk when that
product is relatively expensive.
420. The “past research” mentioned in line 25 suggests
which of the following about perceived performance
risk?
(A) The more expensive a new product is, the more
likely consumers may be to credit advertised
claims about that product.
(B) The more familiar consumers are with a
particular manufacturer, the more willing they
may be to assume some risk in the purchase
of a new product being advertised by that
manufacturer.
(C) Consumers’ perception of the performance risk
associated with a new product being advertised
may be in uenced by an interplay between the
product’s price and the manufacturer’s credibility.
(D) Consumers may be more likely to believe that
a product will function as it is advertised to
do when they have bought products from a
particular manufacturer before.
(E) The price of a particular advertised product
may have less impact than the manufacturer’s
credibility on consumers’ assessment of the
performance risk associated with that product.
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371
421. The passage is primarily concerned with
(A) challenging the implications of previous research
into why consumers try new products
(B) suggesting new marketing strategies for
attracting consumers to new products
(C) reconciling two different views about the effect
of price on consumers’ willingness to try new
products
(D) describing a new approach to researching why
consumers try new products
(E) discussing certain ndings regarding why
consumers try new products
422. Which of the following, if true, would most tend to
weaken the conclusions drawn from “some of this
research” (line 8)?
(A) In a subsequent study, consumers who were
asked to evaluate new products with relatively
low prices had the same perception of the
products’ performance risk as did consumers
who were shown the same products priced more
expensively.
(B) In a subsequent study, the quality of the
advertising for the products that consumers
perceived as having a lower performance risk
was relatively high, while the quality of the
advertising for the products that consumers
perceived as having a higher performance risk
was relatively poor.
(C) In a subsequent study, the products that
consumers perceived as having a lower
performance risk were priced higher than the
highest priced products in the previous research.
(D) None of the consumers involved in this research
had ever before bought products from the
manufacturers involved in the research.
(E) Researchers found that the higher the source
credibility for a product, the more consumers
were willing to pay for it.
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
372
Line
(5)
(10)
(15)
(20)
(25)
(30)
(35)
Historians remain divided over the role of
banks in facilitating economic growth in the
United States in the late eighteenth and early
nineteenth centuries. Some scholars contend
that banks played a minor role in the nation’s
growing economy. Financial institutions, they
argue, appeared only after the economy had
begun to develop, and once organized, followed
conservative lending practices, providing aid to
established commercial enterprises but
shunning those, such as manufacturing and
transportation projects, that were more
uncertain and capital‐intensive (i.e., requiring
greater expenditures in the form of capital than in
labor).
A growing number of historians argue, in
contrast, that banks were crucial in transforming
the early national economy. When state
legislatures began granting more bank charters
in the 1790s and early 1800s, the supply of
credit rose accordingly. Unlike the earliest banks,
which had primarily provided short‐term loans to
well‐connected merchants, the banks of the early
nineteenth century issued credit widely. As Paul
Gilje asserts, the expansion and democratization
of credit in the early nineteenth century became
the driving force of the American economy, as
banks began furnishing large amounts of capital
to transportation and industrial enterprises. The
exception, such historians argue, was in the
South; here, the overwhelmingly agrarian nature
of the economy generated outright opposition
to banks, which were seen as monopolistic
institutions controlled by an elite group of
planters.
Questions 423–427 refer to the passage.
423. The primary purpose of the passage is to
(A) compare the economic role played by southern
banks with the economic role played by banks
in the rest of the United States during the late
eighteenth and early nineteenth centuries
(B) reevaluate a conventional interpretation of the
role played by banks in the American economy
during the late eighteenth and early nineteenth
centuries
(C) present different interpretations of the role
played by banks in the American economy during
the late eighteenth and early nineteenth centuries
(D) analyze how the increasing number of banks in
the late eighteenth and early nineteenth centuries
affected the American economy
(E) examine how scholarly opinion regarding the role
played by banks in the American economy during
the late eighteenth and early nineteenth centuries
has changed over time
424. The passage suggests that the scholars mentioned in
line 4 would argue that the reason banks tended not to
fund manufacturing and transportation projects in the
late eighteenth and early nineteenth centuries was that
(A) these projects, being well established and well
capitalized, did not need substantial long‐term
nancing from banks
(B) these projects entailed a level of risk that
was too great for banks’ conservative lending
practices
(C) banks preferred to invest in other, more
speculative projects that offered the potential for
higher returns
(D) bank managers believed that these projects
would be unlikely to contribute signi cantly to
economic growth in the new country
(E) bank managers believed funding these projects
would result in credit being extended to too
many borrowers
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373
425. The passage suggests that Paul Gilje would be most
likely to agree with which of the following claims
about the lending practices of the “earliest banks”
(see line 21)?
(A) These lending practices were unlikely to
generate substantial pro ts for banks.
(B) These lending practices only bene ted a narrow
sector of the economy.
(C) The restrictive nature of these lending practices
generated signi cant opposition outside of the
South.
(D) The restrictive nature of these lending practices
forced state legislatures to begin granting more
bank charters by the early nineteenth century.
(E) These lending practices were likely to be
criticized by economic elites as being overly
restrictive.
426. The passage suggests that the opposition to banks in
the South in the early nineteenth century stemmed in
part from the perception that banks
(A) did not bene t more than a small minority of the
people
(B) did not support the interests of elite planters
(C) were too closely tied to transportation and
industrial interests
(D) were unwilling to issue the long‐term loans
required by agrarian interests
(E) were too willing to lend credit widely
427. Which of the following statements best describes the
function of the last sentence of the passage?
(A) It provides evidence tending to undermine the
viewpoint of the scholars mentioned in line 5.
(B) It resolves a con ict over the role of banks
summarized in the rst paragraph.
(C) It clari es some of the reasons state legislatures
began granting more bank charters.
(D) It quali es a claim made earlier in the passage
about the impact of banks on the American
economy in the early nineteenth century.
(E) It supports a claim made earlier in the passage
about how the expansion of credit affected the
economy.
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
374
Line
(5)
(10)
(15)
(20)
(25)
(30)
Io and Europa, the inner two of Jupiter’s four
largest moons, are about the size of Earth’s moon
and are composed mostly or entirely of rock and
metal. Ganymede and Callisto are larger and roughly
half ice. Thus, these four moons are somewhat
analogous to the planets of the solar system, in which
the rock‐ and metal‐rich inner planets are distinct
from the much larger gas‐ and ice‐rich outer planets.
Jupiter’s moons are, however, more “systematic”:
many of their properties vary continuously with
distance from Jupiter. For example, Io is ice‐free,
Europa has a surface shell of ice, and while
Ganymede and Callisto are both ice‐rich, outermost
Callisto hasmore.
This compositional gradient has geological
parallels. Io is extremely geologically active, Europa
seems to be active on a more modest scale, and
Ganymede has undergone bouts of activity in its
geological past. Only Callisto reveals no geological
activity. In similar fashion, Callisto’s surface is very
heavily cratered from the impact of comets and
asteroids; Ganymede, like Earth’s moon, is heavily
cratered in parts; Europa is very lightly cratered; and
no craters have been detected on Io, even though
Jupiter’s gravity attracts comets and asteroids
passing near it, substantially increasing the
bombardment rate of the inner moons compared
to that of the outer ones. But because of Io’s high
degree of geological activity, its surface undergoes
more‐or‐less continuous volcanic resurfacing.
Questions 428–430 refer to the passage.
428. According to the passage, the difference in the amount
of cratering on Callisto’s and Io’s respective surfaces
can probably be explained by the difference between
these two moons with respect to which of the following
factors?
(A) Size
(B) Ice content
(C) The rate of bombardment by comets and
asteroids
(D) The in uence of Jupiter’s other moons
(E) The level of geological activity
429. Which of the following best describes the purpose of
the second paragraph of the passage?
(A) To provide further evidence of the systematic
variation in the characteristics of Jupiter’s four
largest moons
(B) To present a comprehensive theory to explain
the systematic variation in the characteristics of
Jupiter’s four largest moons
(C) To explain the signi cance of the systematic
variation in the characteristics of Jupiter’s four
largest moons
(D) To introduce facts that contradict conventional
assumptions about Jupiter’s four largest moons
(E) To contrast the characteristics of Jupiter’s four
largest moons with the characteristics of the
planets of the solar system
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375
430. The author’s reference to Jupiter’s gravity in line 25
serves primarily to
(A) indicate why the absence of craters on Io’s
surface is surprising
(B) explain the presence of craters on the surface of
Jupiter’s four largest moons
(C) provide an explanation for the lack of geological
activity on Callisto
(D) contrast Jupiter’s characteristics with the
characteristics of its four largest moons
(E) illustrate the similarity between Jupiter’s four
largest moons and the planets of the solar
system
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
376
Line
(5)
(10)
(15)
(20)
(25)
(30)
In an effort to explain why business acquisitions
often fail, scholars have begun to focus on the role
of top executives of acquired companies. Acquired
companies that retain their top executives tend to
have more successful outcomes than those that do
not. Furthermore, existing research suggests that
retaining the highest‐level top executives, such as the
CEO (chief executive of cer) and COO (chief operating
of cer), is related more positively to postacquisition
success than retaining lower‐ranked top executives.
However, this explanation, while insightful, suffers from
two limitations. First, the focus on positional rank does
not recognize the variation in length of service that
may exist in top executive posts across companies,
nor does it address which particular top executives
(with respect to length of service) should be retained
to achieve a successful acquisition outcome. Second,
the relationship between retained top executives and
acquisition outcomes offered by existing research
is subject to opposing theoretical explanations
related to length of service. The resource‐based view
(RBV) suggests that keeping acquired company top
executives with longer organizational tenure would lead
to more successful outcomes, as those executives
have idiosyncratic and nontransferable knowledge
of the acquired company that would be valuable for
the effective implementation of the acquisition. The
opposing position, offered by the upper echelons
perspective (UEP), suggests that retaining top
executives having short organizational tenure would
lead to more successful outcomes, as they would have
the adaptability to manage most effectively during the
uncertainty of the acquisition process.
( 35)
(40)
(45)
(50)
Responding to these limitations, Bergh conducted
a study of executive retention and acquisition
outcome that focused on the organizational tenure of
retained company top executives in 104 acquisitions,
followed over 5 years. Bergh considered the
acquisition successful if the acquired company was
retained and unsuccessful if it was divested. Bergh’s
ndings support the RBV position. Apparently, the
bene ts of long organizational tenure lead to more
successful outcomes than the bene ts of short
organizational tenure. While longer tenured top
executives may have trouble adapting to change, it
appears that their perspectives and knowledge bases
offer unique value after the acquisition. Although
from the UEP position it seems sensible to retain
less tenured executives and allow more tenured
ones to leave, such a strategy appears to lower the
probability of acquisition success.
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377
Questions 431–434 refer to the passage.
431. According to the passage, the research mentioned
in line 6 suggests which of the following about
lower‐ranked top executives and postacquisition
success?
(A) Given that these executives are unlikely to
contribute to postacquisition success, little effort
should be spent trying to retain them.
(B) The shorter their length of service, the less likely
it is that these executives will play a signi cant
role in postacquisition success.
(C) These executives are less important to
postacquisition success than are more highly
ranked top executives.
(D) If they have long tenures, these executives may
prove to be as important to postacquisition
success as are more highly ranked top
executives.
(E) Postacquisition success is unlikely if these
executives are retained.
432. The resource‐based view, as described in the passage,
is based on which of the following ideas?
(A) The managerial skills of top executives become
strongest after the rst ve years of their tenure.
(B) Company‐speci c knowledge is an important
factor in the success of an acquisition process.
(C) The amount of nontransferable knowledge
possessed by long‐tenured top executives tends
to be underestimated.
(D) Effective implementation of an acquisition
depends primarily on the ability of executives to
adapt to change.
(E) Short‐tenured executives are likely to impede
the implementation of a successful acquisition
strategy.
433. The passage suggests that Bergh and a proponent of
the upper echelons perspective would be most likely to
disagree over which of the following?
(A) Whether there is a positive correlation between
short organizational tenure and managerial
adaptability
(B) Whether there is a positive correlation between
long organizational tenure and the acquisition of
idiosyncratic and nontransferable knowledge
(C) Whether adaptability is a useful trait for an
executive who is managing an acquisition
process
(D) Whether retaining less‐tenured top executives of
an acquired company is an optimal strategy for
achieving postacquisition success
(E) Whether retaining highest‐level top executives
of acquired companies is more important than
retaining lower‐ranked top executives
434. According to the passage, prior to Bergh’s study,
research on the role of top executives of acquired
companies in business acquisition success was limited
in which of the following ways?
(A) It did not address how the organizational
tenure of top executives affects postacquisition
success.
(B) It did not address why some companies have
longer‐tenured CEOs than others.
(C) It did not consider strategies for retaining long‐
tenured top executives of acquired companies.
(D) It failed to differentiate between the contribution
of highest‐level top executives to postacquisition
success and that of lower‐ranked top executives.
(E) It underestimated the potential contribution
that lower‐level top executives can make to
postacquisition success.
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
378
Line
(5)
(10)
(15)
(20)
(25)
(30)
When Jamaican‐born social activist Marcus
Garvey came to the United States in 1916, he
arrived at precisely the right historical moment.
What made the moment right was the return of
African American soldiers from the First World War
in 1918, which created an ideal constituency for
someone with Garvey’s message of unity, pride,
and improved conditions for African American
communities.
Hoping to participate in the traditional American
ethos of individual success, many African American
people entered the armed forces with enthusiasm,
only to nd themselves segregated from white
troops and subjected to numerous indignities. They
returned to a United States that was as segregated
as it had been before the war. Considering similar
experiences, anthropologist Anthony F. C. Wallace
has argued that when a perceptible gap arises
between a culture’s expectations and the reality of
that culture, the resulting tension can inspire a
revitalization movement: an organized, conscious
effort to construct a culture that ful lls long‐
standing expectations.
Some scholars have argued that Garvey created
the consciousness from which he built, in the 1920s,
the largest revitalization movement in
African American history. But such an argument only
tends to obscure the consciousness of
identity, strength, and sense of history that already
existed in the African American community. Garvey
did not create this consciousness; rather, he gave
this consciousness its political expression.
Questions 435–438 refer to the passage.
435. According to the passage, which of the following
contributed to Marcus Garvey’s success?
(A) He introduced cultural and historical
consciousness to the African American
community.
(B) He believed enthusiastically in the traditional
American success ethos.
(C) His audience had already formed a
consciousness that made it receptive to his
message.
(D) His message appealed to critics of African
American support for United States military
involvement in the First World War.
(E) He supported the movement to protest
segregation that had emerged prior to his arrival
in the United States.
436. The passage suggests that many African American
people responded to their experiences in the armed
forces in which of the following ways?
(A) They maintained as civilians their enthusiastic
allegiance to the armed forces.
(B) They questioned United States involvement in the
First World War.
(C) They joined political organizations to protest the
segregation of African American troops and the
indignities they suffered in the military.
(D) They became aware of the gap between their
expectations and the realities of American
culture.
(E) They repudiated Garvey’s message of pride and
unity.
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379
437. It can be inferred from the passage that the “scholars”
mentioned in line 24 believe which of the following to
be true?
(A) Revitalization resulted from the political activism
of returning African American soldiers following
the First World War.
(B) Marcus Garvey had to change a number of
prevailing attitudes in order for his mass
movement to nd a foothold in the United States.
(C) The prevailing sensibility of the African American
community provided the foundation of Marcus
Garvey’s political appeal.
(D) Marcus Garvey hoped to revitalize consciousness
of cultural and historical identity in the African
American community.
(E) The goal of the mass movement that Marcus
Garvey helped bring into being was to build on
the pride and unity among African Americans.
438. According to the passage, many African American
people joined the armed forces during the First World
War for which of the following reasons?
(A) They wished to escape worsening economic
conditions in African American communities.
(B) They expected to ful ll ideals of personal
attainment.
(C) They sought to express their loyalty to the United
States.
(D) They hoped that joining the military would help
advance the cause of desegregation.
(E) They saw military service as an opportunity to
ful ll Marcus Garvey’s political vision.
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
380
Line
(5)
(10)
(15)
(20)
(25)
(30)
In the Sonoran Desert of northwestern Mexico and
southern Arizona, the owers of several species of
columnar cacti—cardon, saguaro, and organ
pipe—were once exclusively pollinated at night by
nectar-feeding bats, as their close relatives in arid
tropical regions of southern Mexico still are. In these
tropical regions, diurnal (daytime) visitors to columnar
cactus owers are ineffective pollinators because,
by sunrise, the owers’ stigmas become unreceptive
or the owers close. Yet the owers of the Sonoran
Desert cacti have evolved to remain open after sunrise,
allowing pollination by such diurnal visitors as bees and
birds. Why have these cacti expanded their range of
pollinators by remaining open and receptive in daylight?
This development at the northernmost range of
columnar cacti may be due to a yearly variation in the
abundance—and hence the reliability—of migratory
nectar-feeding bats. Pollinators can be unreliable
for several reasons. They can be dietary generalists
whose delity to a particular species depends on
the availability of alternative food sources. Or, they
can be dietary specialists, but their abundance may
vary widely from year to year, resulting in variable
pollination of their preferred food species. Finally, they
may be dietary specialists, but their abundance may
be chronically low relative to the availability of owers.
Recent data reveals that during spring in the
Sonoran Desert, the nectar-feeding bats are
specialists feeding on cardon, saguaro, and
organpipe owers. However, whereas cactus- ower
abundance tends to be high during spring, bat
population densities tend to be low except near
maternity roosts. Moreover, in spring, diurnal cactus-
pollinating birds are signi cantly more abundant in
(35)
(40)
(45)
this region than are the nocturnal bats. Thus, with bats
being unreliable cactus- ower pollinators, and daytime
pollinators more abundant and therefore more reliable,
selection favors the cactus owers with traits that
increase their range of pollinators. While data suggest
that population densities of nectar-feeding bats are
also low in tropical areas of southern Mexico, where
bats are the exclusive pollinators of many species
of columnar cacti, cactus- ower density and bat
population density appear to be much more evenly
balanced there: compared with the Sonoran Desert’s
cardon and saguaro, columnar cacti in southern Mexico
produce far fewer owers per night. Accordingly,
despite their low population density, bats are able to
pollinate nearly 100 percent of the available owers.
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381
Questions 439–441 refer to the passage.
439. The primary purpose of the passage is to
(A) compare the adaptive responses of several
species of columnar cacti in the Sonoran Desert
with those in the arid tropical regions of southern
Mexico
(B) discuss some of the possible causes of the
relatively low abundance of migratory nectar-
feeding bats in the Sonoran Desert
(C) provide a possible explanation for a particular
evolutionary change in certain species of
columnar cacti in the Sonoran Desert
(D) present recent ndings that challenge a
particular theory as to why several species
of columnar cacti in the Sonoran Desert have
expanded their range of pollinators
(E) compare the effectiveness of nocturnal and
diurnal pollination for several different species of
columnar cacti in the Sonoran Desert
440. According to the passage, which of the following types
of nectar-feeding pollinators is likely to be an unreliable
pollinator of a particular cactus ower?
(A) A dietary specialist whose abundance is typically
high in relation to that of the ower
(B) A dietary specialist whose abundance is at times
signi cantly lower than that of the ower
(C) A dietary generalist for whom that ower’s
nectar is not a preferred food but is the most
consistently available food
(D) A dietary generalist for whom that ower’s nectar
is slightly preferred to other available foods
(E) A dietary generalist that evolved from a species
of dietary specialists
7.4 Reading Comprehension Practice Questions
441. According to the passage, present-day columnar cacti
in the Sonoran Desert differ from their close relatives
in southern Mexico in that the Sonoran cacti
(A) have owers that remain open after sunset
(B) are pollinated primarily by dietary specialists
(C) can be pollinated by nectar-feeding bats
(D) have stigmas that are unreceptive to pollination
at night
(E) are sometimes pollinated by diurnal pollinators
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GMAT® Offi cial Guide 2018
382
Line
(5)
(10)
(15)
(20)
(25)
(30)
In terrestrial environments, gravity places
special demands on the cardiovascular systems of
animals. Gravitational pressure can cause blood to
pool in the lower regions of the body, making it
dif cult to circulate blood to critical organs such as
the brain. Terrestrial snakes, in particular, exhibit
adaptations that aid in circulating blood against the
force of gravity.
The problem confronting terrestrial snakes is best
illustrated by what happens to sea snakes when
removed from their supportive medium. Because the
vertical pressure gradients within the blood vessels
are counteracted by similar pressure gradients in
the surrounding water, the distribution of blood
throughout the body of sea snakes remains about
the same regardless of their orientation in space,
provided they remain in the ocean. When removed
from the water and tilted at various angles with the
head up, however, blood pressure at their midpoint
drops signi cantly, and at brain level falls to zero.
That many terrestrial snakes in similar spatial
orientations do not experience this kind of circulatory
failure suggests that certain adaptations enable them
to regulate blood pressure more effectively in those
orientations.
One such adaptation is the closer proximity of
the terrestrial snake’s heart to its head, which helps
to ensure circulation to the brain, regardless of the
snake’s orientation in space. The heart of sea snakes
can be located near the middle of the body, a
position that minimizes the work entailed in
circulating blood to both extremities. In arboreal
snakes, however, which dwell in trees and often
assume a vertical posture, the average distance
(35)
(40)
(45)
from the heart to the head can be as little as
15 percent of overall body length. Such a location
requires that blood circulated to the tail of the
snake travel a greater distance back to the heart,
a problem solved by another adaptation. When
climbing, arboreal snakes often pause
momentarily to wiggle their bodies, causing waves
of muscle contraction that advance from the lower
torso to the head. By compressing the veins and
forcing blood forward, these contractions
apparently improve the ow of venous blood
returning to the heart.
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383
Questions 442–449 refer to the passage.
442. The passage provides information in support of which
of the following assertions?
(A) The disadvantages of an adaptation to a
particular feature of an environment often
outweigh the advantages of such an adaptation.
(B) An organism’s reaction to being placed in an
environment to which it is not well adapted can
sometimes illustrate the problems that have
been solved by the adaptations of organisms
indigenous to that environment.
(C) The effectiveness of an organism’s adaptation to
a particular feature of its environment can only
be evaluated by examining the effectiveness with
which organisms of other species have adapted
to a similar feature of a different environment.
(D) Organisms of the same species that inhabit
strikingly different environments will often adapt
in remarkably similar ways to the few features of
those environments that are common.
(E) Different species of organisms living in the same
environment will seldom adapt to features of that
environment in the same way.
443. According to the passage, one reason that the
distribution of blood in the sea snake changes little
while the creature remains in the ocean is that
(A) the heart of the sea snake tends to be located
near the center of its body
(B) pressure gradients in the water surrounding
the sea snake counter the effects of vertical
pressure gradients within its blood vessels
(C) the sea snake assumes a vertical posture less
frequently than do the terrestrial and the arboreal
snake
(D) the sea snake often relies on waves of muscle
contractions to help move blood from the torso
to the head
(E) the force of pressure gradients in the water
surrounding the sea snake exceeds that of
vertical pressure gradients within its circulatory
system
444. It can be inferred from the passage that which of the
following is true of species of terrestrial snakes that
often need to assume a vertical posture?
(A) They are more likely to be susceptible to
circulatory failure in vertical postures than are
sea snakes.
(B) Their hearts are less likely to be located at the
midpoint of their bodies than is the case with sea
snakes.
(C) They cannot counteract the pooling of blood in
lower regions of their bodies as effectively as
sea snakes can.
(D) The blood pressure at their midpoint decreases
signi cantly when they are tilted with their
headsup.
(E) They are unable to rely on muscle contractions
to move venous blood from the lower torso to
the head.
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
384
445. The author describes the behavior of the circulatory
system of sea snakes when they are removed from the
ocean (see lines 17–20) primarily in order to
(A) illustrate what would occur in the circulatory
system of terrestrial snakes without adaptations
that enable them to regulate their blood pressure
in vertical orientations
(B) explain why arboreal snakes in vertical
orientations must rely on muscle contractions to
restore blood pressure to the brain
(C) illustrate the effects of circulatory failure on the
behavior of arboreal snakes
(D) illustrate the superiority of the circulatory system
of the terrestrial snake to that of the sea snake
(E) explain how changes in spatial orientation can
adversely affect the circulatory system of snakes
with hearts located in relatively close proximity
to their heads
446. It can be inferred from the passage that which of the
following is a true statement about sea snakes?
(A) They frequently rely on waves of muscle
contractions from the lower torso to the head to
supplement the work of the heart.
(B) They cannot effectively regulate their blood
pressure when placed in seawater and tilted at
an angle with the head pointed downward.
(C) They are more likely to have a heart located in
close proximity to their heads than are arboreal
snakes.
(D) They become acutely vulnerable to the effects
of gravitational pressure on their circulatory
system when they are placed in a terrestrial
environment.
(E) Their cardiovascular system is not as
complicated as that of arboreal snakes.
447. The author suggests that which of the following is a
disadvantage that results from the location of a snake’s
heart in close proximity to its head?
(A) A decrease in the ef ciency with which the snake
regulates the ow of blood to the brain
(B) A decrease in the number of orientations in
space that a snake can assume without loss of
blood ow to the brain
(C) A decrease in blood pressure at the snake’s
midpoint when it is tilted at various angles with
its head up
(D) An increase in the tendency of blood to pool
at the snake’s head when the snake is tilted at
various angles with its head down
(E) An increase in the amount of effort required to
distribute blood to and from the snake’s tail
448. The primary purpose of the third paragraph is to
(A) introduce a topic that is not discussed earlier in
the passage
(B) describe a more ef cient method of achieving an
effect discussed in the previous paragraph
(C) draw a conclusion based on information
elaborated in the previous paragraph
(D) discuss two speci c examples of phenomena
mentioned at the end of the previous paragraph
(E) introduce evidence that undermines a view
reported earlier in the passage
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385
449. In the passage, the author is primarily concerned with
doing which of the following?
(A) Explaining adaptations that enable the terrestrial
snake to cope with the effects of gravitational
pressure on its circulatory system
(B) Comparing the circulatory system of the sea
snake with that of the terrestrial snake
(C) Explaining why the circulatory system of the
terrestrial snake is different from that of the sea
snake
(D) Pointing out features of the terrestrial snake’s
cardiovascular system that make it superior to
that of the sea snake
(E) Explaining how the sea snake is able to
neutralize the effects of gravitational pressure on
its circulatory system
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
386
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Current feminist theory, in validating women’s own
stories of their experience, has encouraged scholars
of women’s history to view the use of women’s oral
narratives as the methodology, next to the use of
women’s written autobiography, that brings historians
closest to the “reality” of women’s lives. Such
narratives, unlike most standard histories, represent
experience from the perspective of women, af rm
the importance of women’s contributions, and furnish
present‐day women with historical continuity that is
essential to their identity, individually and collectively.
Scholars of women’s history should, however, be
as cautious about accepting oral narratives at face
value as they already are about written memories.
Oral narratives are no more likely than are written
narratives to provide a disinterested commentary on
events or people. Moreover, the stories people tell to
explain themselves are shaped by narrative devices
and storytelling conventions, as well as by other
cultural and historical factors, in ways that the
storytellers may be unaware of. The political rhetoric
of a particular era, for example, may in uence
women’s interpretations of the signi cance of their
experience. Thus a woman who views the Second
World War as pivotal in increasing the social
acceptance of women’s paid work outside the home
may reach that conclusion partly and unwittingly
because of wartime rhetoric encouraging a positive
view of women’s participation in such work.
Questions 450–455 refer to the passage.
450. The passage is primarily concerned with
(A) contrasting the bene ts of one methodology with
the bene ts of another
(B) describing the historical origins and inherent
drawbacks of a particular methodology
(C) discussing the appeal of a particular
methodology and some concerns about its use
(D) showing that some historians’ adoption of a
particular methodology has led to criticism of
recent historical scholarship
(E) analyzing the in uence of current feminist views
on women’s interpretations of their experience
451. According to the passage, which of the following
shapes the oral narratives of women storytellers?
(A) The conventions for standard histories in the
culture in which a woman storyteller lives
(B) The conventions of storytelling in the culture in
which a woman storyteller lives
(C) A woman storyteller’s experience with distinctive
traditions of storytelling developed by the women
in her family of origin
(D) The cultural expectations and experiences of
those who listen to oral narratives
(E) A woman storyteller’s familiarity with the stories
that members of other groups in her culture tell
to explain themselves
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387
452. The author of the passage would be most likely to
make which of the following recommendations to
scholars of women’s history?
(A) They should take into account their own life
experiences when interpreting the oral accounts
of women’s historical experiences.
(B) They should assume that the observations made
in women’s oral narratives are believed by the
intended audience of the story.
(C) They should treat skeptically observations
reported in oral narratives unless the
observations can be con rmed in standard
histories.
(D) They should consider the cultural and historical
context in which an oral narrative was created
before arriving at an interpretation of such a
narrative.
(E) They should rely on information gathered from
oral narratives only when equivalent information
is not available in standard histories.
453. Which of the following best describes the function of
the last sentence of the passage?
(A) It describes an event that historians view as
crucial in recent women’s history.
(B) It provides an example of how political rhetoric
may in uence the interpretations of experience
reported in women’s oral narratives.
(C) It provides an example of an oral narrative that
inaccurately describes women’s experience
during a particular historical period.
(D) It illustrates the point that some women are more
aware than others of the social forces that shape
their oral narratives.
(E) It identi es the historical conditions that led to
the social acceptance of women’s paid work
outside the home.
454. According to the passage, scholars of women’s history
should refrain from doing which of the following?
(A) Relying on traditional historical sources when
women’s oral narratives are unavailable
(B) Focusing on the in uence of political rhetoric on
women’s perceptions to the exclusion of other
equally important factors
(C) Attempting to discover the cultural and historical
factors that in uence the stories women tell
(D) Assuming that the conventions of women’s
written autobiographies are similar to the
conventions of women’s oral narratives
(E) Accepting women’s oral narratives less critically
than they accept women’s written histories
455. According to the passage, each of the following is a
difference between women’s oral narratives and most
standard histories EXCEPT:
(A) Women’s oral histories validate the signi cance
of women’s achievements.
(B) Women’s oral histories depict experience from
the point of view of women.
(C) Women’s oral histories acknowledge the
in uence of well‐known women.
(D) Women’s oral histories present today’s women
with a sense of their historical relationship to
women of the past.
(E) Women’s oral histories are crucial to the
collective identity of today’s women.
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
388
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(45)
Manufacturers have to do more than build large
manufacturing plants to realize economies of scale.
Itis true that as the capacity of a manufacturing
operation rises, costs per unit of output fall as plant
size approaches “minimum ef cient scale,” where the
cost per unit of output reaches a minimum,
determined roughly by the state of existing technology
and size of the potential market. However, minimum
ef cient scale cannot be fully realized unless a steady
“throughput” (the ow of materials through a plant) is
attained. The throughput needed to maintain the
optimal scale of production requires careful
coordination not only of the ow of goods through the
production process, but also of the ow of input from
suppliers and the ow of output to wholesalers and
nal consumers. If throughput falls below a critical
point, unit costs rise sharply and pro ts disappear. A
manufacturer’s xed costs and “sunk costs” (original
capital investment in the physical plant) do not
decrease when production declines due to inadequate
supplies of raw materials, problems on the factory
oor, or inef cient sales networks. Consequently,
potential economies of scale are based on the
physical and engineering characteristics of the
production facilities—that is, on tangible capital—but
realized economies of scale are operational and
organizational, and depend on knowledge, skills,
experience, and teamwork—that is, on organized
human capabilities, or intangible capital.
The importance of investing in intangible capital
becomes obvious when one looks at what happens in
new capital‐intensive manufacturing industries. Such
industries are quickly dominated, not by the rst rms
to acquire technologically sophisticated plants of
theoretically optimal size, but rather by the rst to
exploit the full potential of such plants. Once some
rms achieve this, a market becomes extremely hard
to enter. Challengers must construct comparable
plants and do so after the rst movers have already
worked out problems with suppliers or with new
production processes. Challengers must create
distribution networks and marketing systems in
markets where rst movers have all the contacts and
know‐how. And challengers must recruit management
teams to compete with those that have already
mastered these functional and strategic activities.
Questions 456–460 refer to the passage.
456. The passage suggests that in order for a manufacturer
in a capital‐intensive industry to have a decisive
advantage over competitors making similar products,
the manufacturer must
(A) be the rst in the industry to build production
facilities of theoretically optimal size
(B) make every effort to keep xed and sunk costs
as low as possible
(C) be one of the rst to operate its manufacturing
plants at minimum ef cient scale
(D) produce goods of higher quality than those
produced by direct competitors
(E) stockpile raw materials at production sites in
order to ensure a steady ow of such materials
457. The passage suggests that which of the following is
true of a manufacturer’s xed and sunk costs?
(A) The extent to which they are determined
by market conditions for the goods being
manufactured is frequently underestimated.
(B) If they are kept as low as possible, the
manufacturer is very likely to realize signi cant
pro ts.
(C) They are the primary factor that determines
whether a manufacturer will realize economies of
scale.
(D) They should be on a par with the xed and sunk
costs of the manufacturer’s competitors.
(E) They are not affected by uctuations in a
manufacturing plant’s throughput.
458. In the context of the passage as a whole, the second
paragraph serves primarily to
(A) provide an example to support the argument
presented in the rst paragraph
(B) evaluate various strategies discussed in the rst
paragraph
(C) introduce evidence that undermines the
argument presented in the rst paragraph
(D) anticipate possible objections to the argument
presented in the rst paragraph
(E) demonstrate the potential dangers of a
commonly used strategy
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389
459. The passage LEAST supports the inference that
a manufacturer’s throughput could be adversely
affected by
(A) a mistake in judgment regarding the selection of
a wholesaler
(B) a breakdown in the factory’s machinery
(C) a labor dispute on the factory oor
(D) an increase in the cost per unit of output
(E) a drop in the ef ciency of the sales network
460. The primary purpose of the passage is to
(A) point out the importance of intangible capital for
realizing economies of scale in manufacturing
(B) show that manufacturers frequently gain a
competitive advantage from investment in large
manufacturing facilities
(C) argue that large manufacturing facilities often
fail because of inadequate investment in both
tangible and intangible capital
(D) suggest that most new industries are likely
to be dominated by rms that build large
manufacturing plants early
(E) explain why large manufacturing plants usually
do not help manufacturers achieve economies of
scale
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
390
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A small number of the forest species of
lepidoptera (moths and butter ies, which exist as
caterpillars during most of their life cycle) exhibit
regularly recurring patterns of population growth
and decline—such uctuations in population are
known as population cycles. Although many different
variables in uence population levels, a regular pattern
such as a population cycle seems to imply a
dominant, driving force. Identi cation of that driving
force, however, has proved surprisingly elusive
despite considerable research. The common
approach of studying causes of population cycles by
measuring the mortality caused by different agents,
such as predatory birds or parasites, has been
unproductive in the case of lepidoptera. Moreover,
population ecologists’ attempts to alter cycles by
changing the caterpillars’ habitat and by reducing
caterpillar populations have not succeeded. In short,
the evidence implies that these insect populations, if
not self‐regulating, may at least be regulated by an
agent more intimately connected with the insect than
are predatory birds or parasites.
Recent work suggests that this agent may be a
virus. For many years, viral disease had been reported
in declining populations of caterpillars, but population
ecologists had usually considered viral disease to
have contributed to the decline once it was underway
rather than to have initiated it. The recent work has
been made possible by new techniques of molecular
biology that allow viral DNA to be detected at low
concentrations in the environment. Nuclear
polyhedrosis viruses are hypothesized to be the
driving force behind population cycles in lepidoptera
in part because the viruses themselves follow an
infectious cycle in which, if protected from direct
sunlight, they may remain virulent for many years
in the environment, embedded in durable crystals of
polyhedrin protein. Once ingested by a caterpillar,
the crystals dissolve, releasing the virus to infect
the insect’s cells. Late in the course of the infection,
millions of new virus particles are formed and
enclosed in polyhedrin crystals. These crystals
reenter the environment after the insect dies and
decomposes, thus becoming available to infect
other caterpillars.
One of the attractions of this hypothesis is its broad
applicability. Remarkably, despite signi cant differences
in habitat and behavior, many species of lepidoptera
have population cycles of similar length, between eight
and eleven years. Nuclear polyhedrosis viral infection is
one factor these disparate species share.
Questions 461–466 refer to the passage.
461. The primary purpose of the passage is to
(A) describe the development of new techniques that
may help to determine the driving force behind
population cycles in lepidoptera
(B) present evidence that refutes a particular theory
about the driving force behind population cycles
in lepidoptera
(C) present a hypothesis about the driving force
behind population cycles in lepidoptera
(D) describe the uctuating patterns of population
cycles in lepidoptera
(E) question the idea that a single driving force is
behind population cycles in lepidoptera
462. It can be inferred from the passage that the mortality
caused by agents such as predatory birds or parasites
was measured in an attempt to
(A) develop an explanation for the existence of
lepidoptera population cycles
(B) identify behavioral factors in lepidoptera that
affect survival rates
(C) identify possible methods for controlling
lepidoptera population growth
(D) provide evidence that lepidoptera populations
are self‐regulating
(E) determine the life stages of lepidoptera at which
mortality rates are highest
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391
463. Which of the following, if true, would most weaken the
author’s conclusion in lines 18–22 ?
(A) New research reveals that the number of species
of birds and parasites that prey on lepidoptera
has dropped signi cantly in recent years.
(B) New experiments in which the habitats of
lepidoptera are altered in previously untried ways
result in the shortening of lepidoptera population
cycles.
(C) Recent experiments have revealed that the
nuclear polyhedrosis virus is present in a number
of predators and parasites of lepidoptera.
(D) Differences among the habitats of lepidoptera
species make it dif cult to assess the effects of
weather on lepidoptera population cycles.
(E) Viral disease is typically observed in a large
proportion of the lepidoptera population.
464. According to the passage, before the discovery of
new techniques for detecting viral DNA, population
ecologists believed that viral diseases
(A) were not widely prevalent among insect
populations generally
(B) affected only the caterpillar life stage of
lepidoptera
(C) were the driving force behind lepidoptera
population cycles
(D) attacked already declining caterpillar populations
(E) infected birds and parasites that prey on various
species of lepidoptera
465. According to the passage, nuclear polyhedrosis
viruses can remain virulent in the environment only
when
(A) the polyhedrin protein crystals dissolve
(B) caterpillar populations are in decline
(C) they are present in large numbers
(D) their concentration in a particular area remains
low
(E) they are sheltered from direct sunlight
466. It can be inferred from the passage that while inside its
polyhedrin protein crystals, the nuclear polyhedrosis
virus
(A) is exposed to direct sunlight
(B) is attractive to predators
(C) cannot infect caterpillars’ cells
(D) cannot be ingested by caterpillars
(E) cannot be detected by new techniques of
molecular biology
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
392
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Resin is a plant secretion that hardens when
exposed to air; fossilized resin is called amber.
Although Pliny in the rst century recognized that
amber was produced from “marrow discharged by
trees,” amber has been widely misunderstood to be
a semiprecious gem and has even been described
in mineralogy textbooks. Confusion also persists
surrounding the term “resin,” which was de ned
before rigorous chemical analyses were available.
Resin is often confused with gum, a substance
produced in plants in response to bacterial infections,
and with sap, an aqueous solution transported
through certain plant tissues. Resin differs from both
gum and sap in that scientists have not determined a
physiological function for resin.
In the 1950s, entomologists posited that resin
may function to repel or attract insects. Fraenkel
conjectured that plants initially produced resin in
nonspeci c chemical responses to insect attack
and that, over time, plants evolved that produced
resin with speci c repellent effects. But some insect
species, he noted, might overcome the repellent
effects, actually becoming attracted to the resin.
This might induce the insects to feed on those
plants or aid them in securing a breeding site.
Later researchers suggested that resin mediates
the complex interdependence, or “coevolution,” of
plants and insects over time. Such ideas led to the
development of the specialized discipline of chemical
ecology, which is concerned with the role of plant
chemicals in interactions with other organisms and
with the evolution and ecology of plant antiherbivore
chemistry (plants’ chemical defenses against attack
by herbivores such as insects).
Questions 467–470 refer to the passage.
467. According to the passage, which of the following is
true of plant antiherbivore chemistry?
(A) Changes in a plant’s antiherbivore chemistry may
affect insect feeding behavior.
(B) A plant’s repellent effects often involve
interactions between gum and resin.
(C) A plant’s antiherbivore responses assist in
combating bacterial infections.
(D) Plant antiherbivore chemistry plays only a minor
role in the coevolution of plants and insects.
(E) Researchers rst studied repellent effects in
plants beginning in the 1950s.
468. Of the following topics, which would be most likely to
be studied within the discipline of chemical ecology as
it is described in the passage?
(A) Seeds that become attached to certain insects,
which in turn carry away the seeds and aid in
the reproductive cycle of the plant species in
question
(B) An insect species that feeds on weeds
detrimental to crop health and yield, and how
these insects might aid in agricultural production
(C) The effects of deforestation on the life cycles
of subtropical carnivorous plants and the insect
species on which the plants feed
(D) The growth patterns of a particular species of
plant that has proved remarkably resistant to
herbicides
(E) Insects that develop a tolerance for feeding on a
plant that had previously been toxic to them, and
the resultant changes within that plant species
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393
469. The author refers to “bacterial infections” (see line 11)
most likely in order to
(A) describe the physiological function that gum
performs in plants
(B) demonstrate that sap is not the only substance
that is transported through a plant’s tissues
(C) explain how modern chemical analysis has been
used to clarify the function of resin
(D) show that gum cannot serve as an effective
defense against herbivores
(E) give an example of how confusion has arisen
with regard to the nature of resin
470. The author of the passage refers to Pliny most
probably in order to
(A) give an example of how the nature of amber has
been misunderstood in the past
(B) show that confusion about amber has long been
more pervasive than confusion about resin
(C) make note of the rst known reference to amber
as a semiprecious gem
(D) point out an exception to a generalization about
the history of people’s understanding of amber
(E) demonstrate that Pliny believed amber to be a
mineral
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
394
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During the 1980s, many economic historians
studying Latin America focused on the impact of
the Great Depression of the 1930s. Most of these
historians argued that although the Depression
began earlier in Latin America than in the United
States, it was less severe in Latin America and did
not signi cantly impede industrial growth there.
The historians’ argument was grounded in national
government records concerning tax revenues and
exports and in government‐sponsored industrial
censuses, from which historians have drawn
conclusions about total manufacturing output
and pro t levels across Latin America. However,
economic statistics published by Latin American
governments in the early twentieth century are
neither reliable nor consistent; this is especially
true of manufacturing data, which were gathered
from factory owners for taxation purposes and
which therefore may well be distorted. Moreover,
one cannot assume a direct correlation between
the output level and the pro t level of a given
industry as these variables often move in opposite
directions. Finally, national and regional economies
are composed of individual rms and industries,
and relying on general, sweeping economic
indicators may mask substantial variations among
these different enterprises. For example, recent
analyses of previously unexamined data on textile
manufacturing in Brazil and Mexico suggest that the
Great Depression had a more severe impact on this
Latin American industry than scholars
had recognized.
Questions 471–473 refer to the passage.
471. The primary purpose of the passage is to
(A) compare the impact of the Great Depression
on Latin America with its impact on the United
States
(B) criticize a school of economic historians for
failing to analyze the Great Depression in Latin
America within a global context
(C) illustrate the risks inherent in comparing different
types of economic enterprises to explain
economic phenomena
(D) call into question certain scholars’ views
concerning the severity of the Great Depression
in Latin America
(E) demonstrate that the Great Depression had
a more severe impact on industry in Latin
America than in certain other regions
472. Which of the following conclusions about the Great
Depression is best supported by the passage?
(A) It did not impede Latin American industrial
growth as much as historians had previously
thought.
(B) It had a more severe impact on the Brazilian and
the Mexican textile industries than it had on Latin
America as a region.
(C) It affected the Latin American textile industry
more severely than it did any other industry in
Latin America.
(D) The overall impact on Latin American industrial
growth should be reevaluated by economic
historians.
(E) Its impact on Latin America should not be
compared with its impact on the United States.
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395
473. Which of the following, if true, would most strengthen
the author’s assertion regarding economic indicators in
lines 25–27 ?
(A) During an economic depression, European textile
manufacturers’ pro ts rise while their industrial
output remains steady.
(B) During a national economic recession, United
States microchips manufacturers’ pro ts rise
sharply while United States steel manufacturers’
pro ts plunge.
(C) During the years following a severe economic
depression, textile manufacturers’ output levels
and pro t levels increase in Brazil and Mexico
but not in the rest of Latin America.
(D) Although Japanese industry as a whole recovers
after an economic recession, it does not regain
its previously high levels of production.
(E) While European industrial output increases in the
years following an economic depression, total
output remains below that of Japan or the United
States.
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
396
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Among the myths taken as fact by the
environmental managers of most corporations is
the belief that environmental regulations affect all
competitors in a given industry uniformly. In reality,
regulatory costs—and therefore compliance—
fall unevenly, economically disadvantaging some
companies and bene ting others. For example, a
plant situated near a number of larger
noncompliant competitors is less likely to attract
the attention of local regulators than is an isolated
plant, and less attention means lower costs.
Additionally, large plants can spread compliance
costs such as waste treatment across a larger
revenue base; on the other hand, some smaller
plants may not even be subject to certain
provisions such as permit or reporting
requirements by virtue of their size. Finally, older
production technologies often continue to generate
toxic wastes that were not regulated when the
technology was rst adopted. New regulations
have imposed extensive compliance costs on
companies still using older industrial coal‐ red
burners that generate high sulfur dioxide and
nitrogen oxide outputs, for example, whereas new
facilities generally avoid processes that would
create such waste products. By realizing that they
have discretion and that not all industries are
affected equally by environmental regulation,
environmental managers can help their companies
to achieve a competitive edge by anticipating
regulatory pressure and exploring all possibilities for
addressing how changing regulations will affect their
companies speci cally.
Questions 474–477 refer to the passage.
474. It can be inferred from the passage that a large plant
might have to spend more than a similar but smaller
plant on environmental compliance because the larger
plant is
(A) more likely to attract attention from local
regulators
(B) less likely to be exempt from permit and
reporting requirements
(C) less likely to have regulatory costs passed on to
it by companies that supply its raw materials
(D) more likely to employ older production
technologies
(E) more likely to generate wastes that are more
environmentally damaging than those generated
by smaller plants
475. According to the passage, which of the following
statements about sulfur dioxide and nitrogen oxide
outputs is true?
(A) Older production technologies cannot be
adapted so as to reduce production of these
outputs as waste products.
(B) Under the most recent environmental regulations,
industrial plants are no longer permitted to
produce these outputs.
(C) Although these outputs are environmentally
hazardous, some plants still generate them as
waste products despite the high compliance
costs they impose.
(D) Many older plants have developed innovative
technological processes that reduce the
amounts of these outputs generated as waste
products.
(E) Since the production processes that generate
these outputs are less costly than alternative
processes, these less expensive processes are
sometimes adopted despite their acknowledged
environmental hazards.
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476. Which of the following best describes the relationship
of the statement about large plants (lines 12–17) to
the passage as a whole?
(A) It presents a hypothesis that is disproved later in
the passage.
(B) It highlights an opposition between two ideas
mentioned in the passage.
(C) It provides examples to support a claim made
earlier in the passage.
(D) It exempli es a misconception mentioned earlier
in the passage.
(E) It draws an analogy between two situations
described in the passage.
477. The primary purpose of the passage is to
(A) address a widespread environmental
management problem and suggest possible
solutions
(B) illustrate varying levels of compliance with
environmental regulation among different
corporations
(C) describe the various alternatives to traditional
methods of environmental management
(D) advocate increased corporate compliance with
environmental regulation
(E) correct a common misconception about the
impact of environmental regulations
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
398
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Milankovitch proposed in the early twentieth
century that the ice ages were caused by variations
in the Earth’s orbit around the Sun. For some time
this theory was considered untestable, largely
because there was no suf ciently precise
chronology of the ice ages with which the orbital
variations could be matched.
To establish such a chronology it is necessary to
determine the relative amounts of land ice that
existed at various times in the Earth’s past. A
recent discovery makes such a determination
possible: relative land‐ice volume for a given period
can be deduced from the ratio of two oxygen
isotopes, 16 and 18, found in ocean sediments.
Almost all the oxygen in water is oxygen 16, but a
few molecules out of every thousand incorporate the
heavier isotope 18. When an ice age begins, the
continental ice sheets grow, steadily reducing the
amount of water evaporated from the ocean that
will eventually return to it. Because heavier
isotopes tend to be left behind when water
evaporates from the ocean surfaces, the remaining
ocean water becomes progressively enriched in
oxygen 18. The degree of enrichment can be
determined by analyzing ocean sediments of the
period, because these sediments are composed of
calcium carbonate shells of marine organisms,
shells that were constructed with oxygen atoms
drawn from the surrounding ocean. The higher the
ratio of oxygen 18 to oxygen 16 in a sedimentary
specimen, the more land ice there was when the
sediment was laid down.
As an indicator of shifts in the Earth’s climate,
the isotope record has two advantages. First, it is a
global record: there is remarkably little variation in
isotope ratios in sedimentary specimens taken from
different continental locations. Second, it is a
more continuous record than that taken from rocks
on land. Because of these advantages, sedimentary
evidence can be dated with suf cient accuracy
by radiometric methods to establish a precise
chronology of the ice ages. The dated isotope
record shows that the uctuations in global ice
volume over the past several hundred thousand
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years have a pattern: an ice age occurs roughly once
every 100,000 years. These data have established
a strong connection between variations in the Earth’s
orbit and the periodicity of the ice ages.
However, it is important to note that other
factors, such as volcanic particulates or variations
in the amount of sunlight received by the Earth,
could potentially have affected the climate. The
advantage of the Milankovitch theory is that it
is testable; changes in the Earth’s orbit can be
calculated and dated by applying Newton’s laws of
gravity to progressively earlier con gurations of the
bodies in the solar system. Yet the lack of
information about other possible factors affecting
global climate does not make them unimportant.
Questions 478–483 refer to the passage.
478. In the passage, the author is primarily interested in
(A) suggesting an alternative to an outdated
research method
(B) introducing a new research method that calls an
accepted theory into question
(C) emphasizing the instability of data gathered from
the application of a new scienti c method
(D) presenting a theory and describing a new
method to test that theory
(E) initiating a debate about a widely accepted
theory
479. The author of the passage would be most likely to
agree with which of the following statements about the
Milankovitch theory?
(A) It is the only possible explanation for the ice
ages.
(B) It is too limited to provide a plausible explanation
for the ice ages, despite recent research
ndings.
(C) It cannot be tested and con rmed until further
research on volcanic activity is done.
(D) It is one plausible explanation, though not the
only one, for the ice ages.
(E) It is not a plausible explanation for the ice ages,
although it has opened up promising possibilities
for future research.
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399
480. It can be inferred from the passage that the isotope
record taken from ocean sediments would be less
useful to researchers if which of the following were
true?
(A) It indicated that lighter isotopes of oxygen
predominated at certain times.
(B) It had far more gaps in its sequence than the
record taken from rocks on land.
(C) It indicated that climate shifts did not occur
every 100,000 years.
(D) It indicated that the ratios of oxygen 16 and
oxygen 18 in ocean water were not consistent
with those found in fresh water.
(E) It stretched back for only a million years.
481. According to the passage, which of the following
is true of the ratios of oxygen isotopes in ocean
sediments?
(A) They indicate that sediments found during an
ice age contain more calcium carbonate than
sediments formed at other times.
(B) They are less reliable than the evidence from
rocks on land in determining the volume of land
ice.
(C) They can be used to deduce the relative volume
of land ice that was present when the sediment
was laid down.
(D) They are more unpredictable during an ice age
than in other climatic conditions.
(E) They can be used to determine atmospheric
conditions at various times in the past.
482. It can be inferred from the passage that precipitation
formed from evaporated ocean water has
(A) the same isotopic ratio as ocean water
(B) less oxygen 18 than does ocean water
(C) less oxygen 18 than has the ice contained in
continental ice sheets
(D) a different isotopic composition than has
precipitation formed from water on land
(E) more oxygen 16 than has precipitation formed
from fresh water
483. It can be inferred from the passage that calcium
carbonate shells
(A) are not as susceptible to deterioration as rocks
(B) are less common in sediments formed during an
ice age
(C) are found only in areas that were once covered
by land ice
(D) contain radioactive material that can be used to
determine a sediment’s isotopic composition
(E) re ect the isotopic composition of the water at
the time the shells were formed
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
400
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Two works published in 1984 demonstrate
contrasting approaches to writing the history of
United States women. Buel and Buel’s biography
of Mary Fish (1736–1818) makes little effort to
place her story in the context of recent
historiography on women. Lebsock, meanwhile,
attempts not only to write the history of women in
one southern community, but also to redirect two
decades of historiographical debate as to
whether women gained or lost status in the
nineteenth century as compared with the
eighteenth century. Although both books offer the
reader the opportunity to assess this controversy
regarding women’s status, only Lebsock’s deals with
it directly. She examines several different aspects
of women’s status, helping to re ne and resolve the
issues. She concludes that while
women gained autonomy in some areas,
especially in the private sphere, they lost it in
many aspects of the economic sphere. More
importantly, she shows that the debate itself
depends on frame of reference: in many respects,
women lost power in relation to men, for example,
as certain jobs (delivering babies, supervising
schools) were taken over by men. Yet women also
gained power in comparison with their previous
status, owning a higher proportion of real estate,
for example. In contrast, Buel and Buel’s
biography provides ample raw material for
questioning the myth, fostered by some
historians, of a colonial golden age in the
eighteenth century but does not give the reader
much guidance in analyzing the controversy over
women’s status.
Questions 484–489 refer to the passage.
484. The primary purpose of the passage is to
(A) examine two sides of a historiographical debate
(B) call into question an author’s approach to a
historiographical debate
(C) examine one author’s approach to a
historiographical debate
(D) discuss two authors’ works in relationship to a
historiographical debate
(E) explain the prevalent perspective on a
historiographical debate
485. The author of the passage mentions the supervision of
schools primarily in order to
(A) remind readers of the role education played in
the cultural changes of the nineteenth century in
the United States
(B) suggest an area in which nineteenth‐century
American women were relatively free to exercise
power
(C) provide an example of an occupation for which
accurate data about women’s participation are
dif cult to obtain
(D) speculate about which occupations were
considered suitable for United States women of
the nineteenth century
(E) illustrate how the answers to questions about
women’s status depend on particular contexts
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401
486. With which of the following characterizations of
Lebsock’s contribution to the controversy concerning
women’s status in the nineteenth‐century United States
would the author of the passage be most likely to
agree?
(A) Lebsock has studied women from a formerly
neglected region and time period.
(B) Lebsock has demonstrated the importance of
frame of reference in answering questions about
women’s status.
(C) Lebsock has addressed the controversy by using
women’s current status as a frame of reference.
(D) Lebsock has analyzed statistics about
occupations and property that were previously
ignored.
(E) Lebsock has applied recent historiographical
methods to the biography of a nineteenth‐century
woman.
487. According to the passage, Lebsock’s work differs from
Buel and Buel’s work in that Lebsock’s work
(A) uses a large number of primary sources
(B) ignores issues of women’s legal status
(C) refuses to take a position on women’s status in
the eighteenth century
(D) addresses larger historiographical issues
(E) fails to provide suf cient material to support its
claims
488. The passage suggests that Lebsock believes that
compared to nineteenth‐century American women,
eighteenth‐century American women were
(A) in many respects less powerful in relation to men
(B) more likely to own real estate
(C) generally more economically independent
(D) more independent in conducting their private
lives
(E) less likely to work as school superintendents
489. The passage suggests that Buel and Buel’s biography
of Mary Fish provides evidence for which of the
following views of women’s history?
(A) Women have lost power in relation to men since
the colonial era.
(B) Women of the colonial era were not as likely to
be concerned with their status as were women in
the nineteenth century.
(C) The colonial era was not as favorable for women
as some historians have believed.
(D) Women had more economic autonomy in the
colonial era than in the nineteenth century.
(E) Women’s occupations were generally more
respected in the colonial era than in the
nineteenth century.
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
402
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Acting on the recommendation of a British
government committee investigating the high
incidence in white lead factories of illness among
employees, most of whom were women, the Home
Secretary proposed in 1895 that Parliament enact
legislation that would prohibit women from holding
most jobs in white lead factories. Although the
Women’s Industrial Defence Committee (WIDC),
formed in 1892 in response to earlier legislative
attempts to restrict women’s labor, did not discount
the white lead trade’s potential health dangers, it
opposed the proposal, viewing it as yet another
instance of limiting women’s work opportunities.
Also opposing the proposal was the Society for
Promoting the Employment of Women (SPEW),
which attempted to challenge it by investigating the
causes of illness in white lead factories. SPEW
contended, and WIDC concurred, that controllable
conditions in such factories were responsible for
the development of lead poisoning. SPEW provided
convincing evidence that lead poisoning could be
avoided if workers were careful and clean and if
already extant workplace safety regulations were
stringently enforced. However, the Women’s Trade
Union League (WTUL), which had ceased in the late
1880s to oppose restrictions on women’s labor,
supported the eventually enacted proposal, in part
because safety regulations were generally not being
enforced in white lead factories, where there were
no unions (and little prospect of any) to pressure
employers to comply with safety regulations.
Questions 490–492 refer to the passage.
490. The passage suggests that WIDC differed from WTUL
in which of the following ways?
(A) WIDC believed that the existing safety regulations
were adequate to protect women’s health,
whereas WTUL believed that such regulations
needed to be strengthened.
(B) WIDC believed that unions could not succeed
in pressuring employers to comply with such
regulations, whereas WTUL believed that unions
could succeed in doing so.
(C) WIDC believed that lead poisoning in white
lead factories could be avoided by controlling
conditions there, whereas WTUL believed that
lead poisoning in such factories could not
be avoided no matter how stringently safety
regulations were enforced.
(D) At the time that the legislation concerning white
lead factories was proposed, WIDC was primarily
concerned with addressing health conditions
in white lead factories, whereas WTUL was
concerned with improving working conditions in
all types of factories.
(E) At the time that WIDC was opposing legislative
attempts to restrict women’s labor, WTUL had
already ceased to do so.
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491. Which of the following, if true, would most clearly
support the contention attributed to SPEW in lines
17–20 ?
(A) Those white lead factories that most strongly
enforced regulations concerning worker safety
and hygiene had the lowest incidences of lead
poisoning among employees.
(B) The incidence of lead poisoning was much
higher among women who worked in white lead
factories than among women who worked in
other types of factories.
(C) There were many household sources of lead
that could have contributed to the incidence of
lead poisoning among women who also worked
outside the home in the late nineteenth century.
(D) White lead factories were more stringent than
were certain other types of factories in their
enforcement of workplace safety regulations.
(E) Even brief exposure to the conditions typically
found in white lead factories could cause lead
poisoning among factory workers.
492. The passage is primarily concerned with
(A) presenting various groups’ views of the motives
of those proposing certain legislation
(B) contrasting the reasoning of various groups
concerning their positions on certain proposed
legislation
(C) tracing the process whereby certain proposed
legislation was eventually enacted
(D) assessing the success of tactics adopted by
various groups with respect to certain proposed
legislation
(E) evaluating the arguments of various groups
concerning certain proposed legislation
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
404
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It is an odd but indisputable fact that the
seventeenth‐century English women who are
generally regarded as among the forerunners of
modern feminism are almost all identi ed with the
Royalist side in the con ict between Royalists and
Parliamentarians known as the English Civil Wars.
Since Royalist ideology is often associated with the
radical patriarchalism of seventeenth‐century
political theorist Robert Filmer—a patriarchalism
that equates family and kingdom and asserts the
divinely ordained absolute power of the king and,
by analogy, of the male head of the household—
historians have been understandably puzzled by the
fact that Royalist women wrote the earliest
extended criticisms of the absolute subordination
of women in marriage and the earliest systematic
assertions of women’s rational and moral equality
with men. Some historians have questioned the
facile equation of Royalist ideology with Filmerian
patriarchalism; and indeed, there may have been
no consistent differences between Royalists and
Parliamentarians on issues of family organization
and women’s political rights, but in that case one
would expect early feminists to be equally divided
between the two sides.
Catherine Gallagher argues that Royalism
engendered feminism because the ideology of
absolute monarchy provided a transition to an
ideology of the absolute self. She cites the example
of the notoriously eccentric author Margaret
Cavendish (1626–1673), duchess of Newcastle.
Cavendish claimed to be as ambitious as any
woman could be, but knowing that as a woman she
was excluded from the pursuit of power in the real
world, she resolved to be mistress of her own
world, the “immaterial world” that any person can
create within her own mind—and, as a writer, on
paper. In proclaiming what she called her
“singularity,” Cavendish insisted that she was a
(40)
(45)
(50)
self‐suf cient being within her mental empire, the
center of her own subjective universe rather than a
satellite orbiting a dominant male planet. In
justifying this absolute singularity, Cavendish
repeatedly invoked the model of the absolute
monarch, a gure that became a metaphor for the
self‐enclosed, autonomous nature of the individual
person. Cavendish’s successors among early
feminists retained her notion of woman’s sovereign
self, but they also sought to break free from the
complete political and social isolation that her
absolute singularity entailed.
Questions 493–498 refer to the passage.
493. The author of the passage refers to Robert Filmer (see
line 9) primarily in order to
(A) show that Royalist ideology was somewhat more
radical than most historians appear to realize
(B) qualify the claim that patriarchalism formed the
basis of Royalist ideology
(C) question the view that most early feminists were
associated with the Royalist faction
(D) highlight an apparent tension between Royalist
ideology and the ideas of early feminists
(E) argue that Royalists held con icting opinions
on issues of family organization and women’s
political rights
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494. The passage suggests which of the following about
the seventeenth‐century English women mentioned
in line 2 ?
(A) Their status as forerunners of modern feminism
is not entirely justi ed.
(B) They did not openly challenge the radical
patriarchalism of Royalist Filmerian ideology.
(C) Cavendish was the rst among these women to
criticize women’s subordination in marriage and
assert women’s equality with men.
(D) Their views on family organization and women’s
political rights were diametrically opposed to
those of both Royalist and Parliamentarian
ideology.
(E) Historians would be less puzzled if more of them
were identi ed with the Parliamentarian side in
the English Civil Wars.
495. The passage suggests that Margaret Cavendish’s
decision to become an author was motivated, at least
in part, by a desire to
(A) justify her support for the Royalist cause
(B) encourage her readers to work toward
eradicating Filmerian patriarchalism
(C) persuade other women to break free from their
political and social isolation
(D) analyze the causes for women’s exclusion from
the pursuit of power
(E) create a world over which she could exercise
total control
496. The phrase “a satellite orbiting a dominant male planet”
(lines 41–42) refers most directly to
(A) Cavendish’s concept that each woman is a
sovereign self
(B) the complete political and social isolation of
absolute singularity
(C) the immaterial world that a writer can create on
paper
(D) the absolute subordination of women in a
patriarchal society
(E) the metaphorical gure of the absolute monarch
497. The primary purpose of the passage is to
(A) trace the historical roots of a modern
sociopolitical movement
(B) present one scholar’s explanation for a puzzling
historical phenomenon
(C) contrast two interpretations of the ideological
origins of a political con ict
(D) establish a link between the ideology of
an in uential political theorist and that of a
notoriously eccentric writer
(E) call attention to some points of agreement
between opposing sides in an ideological debate
498. Which of the following, if true, would most clearly
undermine Gallagher’s explanation of the link between
Royalism and feminism?
(A) Because of their privileged backgrounds,
Royalist women were generally better educated
than were their Parliamentarian counterparts.
(B) Filmer himself had read some of Cavendish’s
early writings and was highly critical of her ideas.
(C) Cavendish’s views were highly individual and
were not shared by the other Royalist women
who wrote early feminist works.
(D) The Royalist and Parliamentarian ideologies
were largely in agreement on issues of family
organization and women’s political rights.
(E) The Royalist side included a sizable minority
faction that was opposed to the more radical
tendencies of Filmerian patriarchalism.
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
406
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Frazier and Mosteller assert that medical research
could be improved by a move toward larger, simpler
clinical trials of medical treatments. Currently,
researchers collect far more background information
on patients than is strictly required for their trials—
substantially more than hospitals collect—thereby
escalating costs of data collection, storage, and
analysis. Although limiting information collection
could increase the risk that researchers will overlook
facts relevant to a study, Frazier and Mosteller
contend that such risk, never entirely eliminable from
research, would still be small in most studies. Only
in research on entirely new treatments are new and
unexpected variables likely to arise.
Frazier and Mosteller propose not only that
researchers limit data collection on individual
patients but also that researchers enroll more
patients in clinical trials, thereby obtaining a more
representative sample of the total population with
the disease under study. Often researchers restrict
study participation to patients who have no ailments
besides those being studied. A treatment judged
successful under these ideal conditions can then be
evaluated under normal conditions. Broadening the
range of trial participants, Frazier and Mosteller
suggest, would enable researchers to evaluate a
treatment’s ef cacy for diverse patients under various
conditions and to evaluate its effectiveness for
different patient subgroups. For example, the value
of a treatment for a progressive disease may vary
according to a patient’s stage of disease. Patients’
ages may also affect a treatment’s ef cacy.
Questions 499–503 refer to the passage.
499. The passage is primarily concerned with
(A) identifying two practices in medical research that
may affect the accuracy of clinical trials
(B) describing aspects of medical research that tend
to drive up costs
(C) evaluating an analysis of certain shortcomings of
current medical research practices
(D) describing proposed changes to the ways in
which clinical trials are conducted
(E) explaining how medical researchers have
traditionally conducted clinical trials and how
such trials are likely to change
500. Which of the following can be inferred from the
passage about a study of the category of patients
referred to in lines 20–22 ?
(A) Its ndings might have limited applicability.
(B) It would be prohibitively expensive in its attempt
to create ideal conditions.
(C) It would be the best way to sample the total
population of potential patients.
(D) It would allow researchers to limit information
collection without increasing the risk that
important variables could be overlooked.
(E) Its ndings would be more accurate if it
concerned treatments for a progressive
disease than if it concerned treatments for a
nonprogressive disease.
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501. It can be inferred from the passage that a study limited
to patients like those mentioned in lines 20–22 would
have which of the following advantages over the kind
of study proposed by Frazier and Mosteller?
(A) It would yield more data and its ndings would be
more accurate.
(B) It would cost less in the long term, though it
would be more expensive in its initial stages.
(C) It would limit the number of variables researchers
would need to consider when evaluating the
treatment under study.
(D) It would help researchers to identify subgroups
of patients with secondary conditions that might
also be treatable.
(E) It would enable researchers to assess the value
of an experimental treatment for the average
patient.
502. The author mentions patients’ ages (line 32) primarily
in order to
(A) identify the most critical variable differentiating
subgroups of patients
(B) cast doubt on the advisability of implementing
Frazier and Mosteller’s proposals about medical
research
(C) indicate why progressive diseases may require
different treatments at different stages
(D) illustrate a point about the value of enrolling a
wide range of patients in clinical trials
(E) substantiate an argument about the problems
inherent in enrolling large numbers of patients in
clinical trials
503. According to the passage, which of the following
describes a result of the way in which researchers
generally conduct clinical trials?
(A) They expend resources on the storage of
information likely to be irrelevant to the study
they are conducting.
(B) They sometimes compromise the accuracy of
their ndings by collecting and analyzing more
information than is strictly required for their
trials.
(C) They avoid the risk of overlooking variables that
might affect their ndings, even though doing so
raises their research costs.
(D) Because they attempt to analyze too much
information, they overlook facts that could
emerge as relevant to their studies.
(E) In order to approximate the conditions typical
of medical treatment, they base their methods
of information collection on those used by
hospitals.
7.4 Reading Comprehension Practice Questions
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GMAT® Offi cial Guide 2018
408
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There are recent reports of apparently drastic
declines in amphibian populations and of extinctions
of a number of the world’s endangered amphibian
species. These declines, if real, may be signs of a
general trend toward extinction, and many
environmentalists have claimed that immediate
environmental action is necessary to remedy
this “amphibian crisis,” which, in their view, is an
indicator of general and catastrophic environmental
degradation due to human activity.
To evaluate these claims, it is useful to make a
preliminary distinction that is far too often ignored.
A declining population should not be confused with
an endangered one. An endangered population is
always rare, almost always small, and, by de nition,
under constant threat of extinction even without a
proximate cause in human activities. Its disappearance,
however unfortunate, should come as no great
surprise. Moreover, chance events—which may
indicate nothing about the direction of trends in
population size—may lead to its extinction. The
probability of extinction due to such random factors
depends on the population size and is independent of
the prevailing direction of change in that size.
For biologists, population declines are potentially
more worrisome than extinctions. Persistent
declines, especially in large populations, indicate a
changed ecological context. Even here, distinctions
must again be made among declines that are only
apparent (in the sense that they are part of habitual
cycles or of normal uctuations), declines that take
a population to some lower but still acceptable
level, and those that threaten extinction (e.g., by
taking the number of individuals below the minimum
viable population). Anecdotal reports of population
decreases cannot distinguish among these
possibilities, and some amphibian populations have
shown strong uctuations in the past.
It is indisputably true that there is simply not
enough long‐term scienti c data on amphibian
populations to enable researchers to identify real
declines in amphibian populations. Many fairly
common amphibian species declared all but extinct
after severe declines in the 1950s and 1960s
have subsequently recovered, and so might
the apparently declining populations that have
generated the current appearance of an amphibian
crisis. Unfortunately, long‐term data will not soon
be forthcoming, and postponing environmental
action while we wait for it may doom species and
whole ecosystems to extinction.
Questions 504–509 refer to the passage.
504. The primary purpose of the passage is to
(A) assess the validity of a certain view
(B) distinguish between two phenomena
(C) identify the causes of a problem
(D) describe a disturbing trend
(E) allay concern about a particular phenomenon
505. It can be inferred from the passage that the author
believes which of the following to be true of the
environmentalists mentioned in lines 5–6?
(A) They have wrongly chosen to focus on anecdotal
reports rather than on the long‐term data that
are currently available concerning amphibians.
(B) Their recommendations are awed because
their research focuses too narrowly on a single
category of animal species.
(C) Their certainty that population declines in general
are caused by environmental degradation is not
warranted.
(D) They have drawn premature conclusions
concerning a crisis in amphibian populations
from recent reports of declines.
(E) They have overestimated the effects of chance
events on trends in amphibian populations.
506. It can be inferred from the passage that the author
believes which of the following to be true of the
amphibian extinctions that have recently been
reported?
(A) They have resulted primarily from human
activities causing environmental degradation.
(B) They could probably have been prevented if
timely action had been taken to protect the
habitats of amphibian species.
(C) They should not come as a surprise, because
amphibian populations generally have been
declining for a number of years.
(D) They have probably been caused by a
combination of chance events.
(E) They do not clearly constitute evidence of
general environmental degradation.
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507. According to the passage, each of the following is true
of endangered amphibian species EXCEPT:
(A) They are among the rarest kinds of amphibians.
(B) They generally have populations that are small in
size.
(C) They are in constant danger of extinction.
(D) Those with decreasing populations are the most
likely candidates for immediate extinction.
(E) They are in danger of extinction due to events
that sometimes have nothing to do with human
activities.
508. Which of the following most accurately describes the
organization of the passage?
(A) A question is raised, a distinction regarding it is
made, and the question is answered.
(B) An interpretation is presented, its soundness is
examined, and a warning is given.
(C) A situation is described, its consequences are
analyzed, and a prediction is made.
(D) Two interpretations of a phenomenon are
described, and one of them is rejected as invalid.
(E) Two methods for analyzing a phenomenon are
compared, and further study of the phenomenon
is recommended.
509. Which of the following best describes the function of
the sentence in lines 35–38?
(A) To give an example of a particular kind of study
(B) To cast doubt on an assertion made in the
previous sentence
(C) To raise an objection to a view presented in the
rst paragraph
(D) To provide support for a view presented in the
rst paragraph
(E) To introduce an idea that will be countered in the
following paragraph
7.4 Reading Comprehension Practice Questions
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While the most abundant and dominant species
within a particular ecosystem is often crucial in
perpetuating the ecosystem, a “keystone” species,
here de ned as one whose effects are much larger
than would be predicted from its abundance, can
also play a vital role. But because complex species
interactions may be involved, identifying a keystone
species by removing the species and observing
changes in the ecosystem is problematic. It might
seem that certain traits would clearly de ne a species
as a keystone species; for example,
Pisaster ochraceus is often a keystone predator
because it consumes and suppresses mussel
populations, which in the absence of this star sh
can be a dominant species. But such predation on a
dominant or potentially dominant species occurs in
systems that do as well as in systems that do not
have species that play keystone roles. Moreover,
whereas P. ochraceus occupies an unambiguous
keystone role on wave‐exposed rocky headlands,
in more wave‐sheltered habitats the impact of
P. ochraceus predation is weak or nonexistent,
and at certain sites sand burial is responsible for
eliminating mussels. Keystone status appears to
depend on context, whether of particular
geography or of such factors as community
diversity (for example, a reduction in species
diversity may thrust more of the remaining species
into keystone roles) and length of species
interaction (since newly arrived species in particular
may dramatically affect ecosystems).
Questions 510–513 refer to the passage.
510. The passage mentions which of the following as
a factor that affects the role of P. ochraceus as a
keystone species within different habitats?
(A) The degree to which the habitat is sheltered from
waves
(B) The degree to which other animals within a
habitat prey on mussels
(C) The fact that mussel populations are often not
dominant within some habitats occupied by
P. ochraceus
(D) The size of the P. ochraceus population within
the habitat
(E) The fact that there is great species diversity
within some habitats occupied by P. ochraceus
511. Which of the following hypothetical experiments most
clearly exempli es the method of identifying species’
roles that the author considers problematic?
(A) A population of seals in an Arctic habitat is
counted in order to determine whether it is the
dominant species in that ecosystem.
(B) A species of sh that is a keystone species in
one marine ecosystem is introduced into another
marine ecosystem to see whether the species
will come to occupy a keystone role.
(C) In order to determine whether a species of
monkey is a keystone species within a particular
ecosystem, the monkeys are removed from that
ecosystem and the ecosystem is then studied.
(D) Different mountain ecosystems are compared to
determine how geography affects a particular
species’ ability to dominate its ecosystem.
(E) In a grassland experiencing a changing climate,
patterns of species extinction are traced in order
to evaluate the effect of climate changes on
keystone species in that grassland.
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512. Which of the following, if true, would most clearly
support the argument about keystone status advanced
in the last sentence of the passage (lines 24–31) ?
(A) A species of bat is primarily responsible for
keeping insect populations within an ecosystem
low, and the size of the insect population in turn
affects bird species within that ecosystem.
(B) A species of iguana occupies a keystone role
on certain tropical islands, but does not play
that role on adjacent tropical islands that are
inhabited by a greater number of animal species.
(C) Close observation of a savannah ecosystem
reveals that more species occupy keystone
roles within that ecosystem than biologists had
previously believed.
(D) As a keystone species of bee becomes more
abundant, it has a larger effect on the ecosystem
it inhabits.
(E) A species of moth that occupies a keystone role
in a prairie habitat develops coloration patterns
that camou age it from potential predators.
513. The passage suggests which of the following about the
identi cation of a species as a keystone species?
(A) Such an identi cation depends primarily on the
species’ relationship to the dominant species.
(B) Such an identi cation can best be made
by removing the species from a particular
ecosystem and observing changes that occur in
the ecosystem.
(C) Such an identi cation is likely to be less reliable
as an ecosystem becomes less diverse.
(D) Such an identi cation seems to depend on
various factors within the ecosystem.
(E) Such an identi cation can best be made by
observing predation behavior.
7.4 Reading Comprehension Practice Questions
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Conodonts, the spiky phosphatic remains (bones
and teeth composed of calcium phosphate) of
tiny marine animals that probably appeared about
520 million years ago, were once among the most
controversial of fossils. Both the nature of the
organism to which the remains belonged and the
function of the remains were unknown. However,
since the 1981 discovery of fossils preserving not
just the phosphatic elements but also other remains
of the tiny soft-bodied animals (also called conodonts)
that bore them, scientists’ reconstructions of the
animals’ anatomy have had important implications
for hypotheses concerning the development of the
vertebrate skeleton.
The vertebrate skeleton had traditionally been
regarded as a defensive development, champions of
this view postulating that it was only with the much
later evolution of jaws that vertebrates became
predators. The rst vertebrates, which were soft-
bodied, would have been easy prey for numerous
invertebrate carnivores, especially if these early
vertebrates were sedentary suspension feeders.
Thus, traditionalists argued, these animals developed
coverings of bony scales or plates, and teeth were
secondary features, adapted from the protective
bony scales. Indeed, external skeletons of this
type are common among the well-known fossils of
ostracoderms, jawless vertebrates that existed from
approximately 500 to 400 million years ago.
(30)
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However, other paleontologists argued that many of
the de nitive characteristics of vertebrates, such as
paired eyes and muscular and skeletal adaptations
for active life, would not have evolved unless the
rst vertebrates were predatory. Teeth were more
primitive than external armor according to this view,
and the earliest vertebrates were predators.
The stiffening notochord along the back of the
body, V-shaped muscle blocks along the sides,
and posterior tail ns help to identify conodonts as
among the most primitive of vertebrates. The lack of
any mineralized structures apart from the elements
in the mouth indicates that conodonts were more
primitive than the armored jawless shes such as the
ostracoderms. It now appears that the hard parts that
rst evolved in the mouth of an animal improved its
ef ciency as a predator, and that aggression rather
than protection was the driving force behind the origin
of the vertebrate skeleton.
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Questions 514–516 refer to the passage.
514. According to the passage, the anatomical evidence
provided by the preserved soft bodies of conodonts
led scientists to conclude that
(A) conodonts had actually been invertebrate
carnivores
(B) conodonts’ teeth were adapted from protective
bony scales
(C) conodonts were primitive vertebrate suspension
feeders
(D) primitive vertebrates with teeth appeared earlier
than armored vertebrates
(E) scientists’ original observations concerning
the phosphatic remains of conodonts were
essentially correct
515. The second paragraph in the passage serves primarily to
(A) outline the signi cance of the 1981 discovery of
conodont remains to the debate concerning the
development of the vertebrate skeleton
(B) contrast the traditional view of the development
of the vertebrate skeleton with a view derived
from the 1981 discovery of conodont remains
(C) contrast the characteristics of the ostracoderms
with the characteristics of earlier soft-bodied
vertebrates
(D) explain the importance of the development of
teeth among the earliest vertebrate predators
(E) present the two sides of the debate concerning
the development of the vertebrate skeleton
7.4 Reading Comprehension Practice Questions
516. It can be inferred that on the basis of the 1981
discovery of conodont remains, paleontologists could
draw which of the following conclusions?
(A) The earliest vertebrates were sedentary
suspension feeders.
(B) Ostracoderms were not the earliest vertebrates.
(C) Defensive armor preceded jaws among
vertebrates.
(D) Paired eyes and adaptations for activity are
de nitive characteristics of vertebrates.
(E) Conodonts were unlikely to have been predators.
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GMAT® Offi cial Guide 2018
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Jon Clark’s study of the effect of the modernization
of a telephone exchange on exchange maintenance
work and workers is a solid contribution to a debate
that encompasses two lively issues in the history and
sociology of technology: technological determinism
and social constructivism.
Clark makes the point that the characteristics of a
technology have a decisive in uence on job skills and
work organization. Put more strongly, technology can
be a primary determinant of social and managerial
organization. Clark believes this possibility has
been obscured by the recent sociological fashion,
exempli ed by Braverman’s analysis, that emphasizes
the way machinery re ects social choices. For
Braverman, the shape of a technological system is
subordinate to the manager’s desire to wrest control
of the labor process from the workers. Technological
change is construed as the outcome of negotiations
among interested parties who seek to incorporate
their own interests into the design and con guration
of the machinery. This position represents the new
mainstream called social constructivism.
The constructivists gain acceptance by
misrepresenting technological determinism:
technological determinists are supposed to believe,
for example, that machinery imposes appropriate
forms of order on society. The alternative to
constructivism, in other words, is to view technology
as existing outside society, capable of directly
in uencing skills and work organization.
Clark refutes the extremes of the constructivists
by both theoretical and empirical arguments.
Theoretically he de nes “technology” in terms of
relationships between social and technical variables.
Attempts to reduce the meaning of technology to
cold, hard metal are bound to fail, for machinery is
just scrap unless it is organized functionally and
supported by appropriate systems of operation and
maintenance. At the empirical level Clark shows how
a change at the telephone exchange from
maintenance‐intensive electromechanical switches
to semielectronic switching systems altered work
tasks, skills, training opportunities, administration,
and organization of workers. Some changes Clark
attributes to the particular way management and
labor unions negotiated the introduction of the
technology, whereas others are seen as arising from
the capabilities and nature of the technology itself.
Thus Clark helps answer the question: “When is
social choice decisive and when are the concrete
characteristics of technology more important?”
Questions 517–524 refer to the passage.
517. The primary purpose of the passage is to
(A) advocate a more positive attitude toward
technological change
(B) discuss the implications for employees of the
modernization of a telephone exchange
(C) consider a successful challenge to the
constructivist view of technological change
(D) challenge the position of advocates of
technological determinism
(E) suggest that the social causes of technological
change should be studied in real situations
518. Which of the following statements about the
modernization of the telephone exchange is supported
by information in the passage?
(A) The new technology reduced the role of
managers in labor negotiations.
(B) The modernization was implemented without the
consent of the employees directly affected by it.
(C) The modernization had an impact that went
signi cantly beyond maintenance routines.
(D) Some of the maintenance workers felt victimized
by the new technology.
(E) The modernization gave credence to the view of
advocates of social constructivism.
519. Which of the following most accurately describes
Clark’s opinion of Braverman’s position?
(A) He respects its wide‐ranging popularity.
(B) He disapproves of its misplaced emphasis on the
in uence of managers.
(C) He admires the consideration it gives to the
attitudes of the workers affected.
(D) He is concerned about its potential to impede
the implementation of new technologies.
(E) He is sympathetic to its concern about the
impact of modern technology on workers.
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520. The information in the passage suggests that which of
the following statements from hypothetical sociological
studies of change in industry most clearly exempli es
the social constructivists’ version of technological
determinism?
(A) It is the available technology that determines
workers’ skills, rather than workers’ skills
in uencing the application of technology.
(B) All progress in industrial technology grows out of
a continuing negotiation between technological
possibility and human need.
(C) Some organizational change is caused by
people; some is caused by computer chips.
(D) Most major technological advances in industry
have been generated through research and
development.
(E) Some industrial technology eliminates jobs, but
educated workers can create whole new skills
areas by the adaptation of the technology.
521. The information in the passage suggests that Clark
believes that which of the following would be true
if social constructivism had not gained widespread
acceptance?
(A) Businesses would be more likely to modernize
without considering the social consequences of
their actions.
(B) There would be greater understanding of the role
played by technology in producing social change.
(C) Businesses would be less likely to understand
the attitudes of employees affected by
modernization.
(D) Modernization would have occurred at a slower
rate.
(E) Technology would have played a greater part in
determining the role of business in society.
522. According to the passage, constructivists employed
which of the following to promote their argument?
(A) Empirical studies of business situations involving
technological change
(B) Citation of managers supportive of their position
(C) Construction of hypothetical situations that
support their view
(D) Contrasts of their view with a misstatement of an
opposing view
(E) Descriptions of the breadth of impact of
technological change
523. The author of the passage uses the expression “are
supposed to” in line 25 primarily in order to
(A) suggest that a contention made by
constructivists regarding determinists is
inaccurate
(B) de ne the generally accepted position of
determinists regarding the implementation of
technology
(C) engage in speculation about the motivation of
determinists
(D) lend support to a comment critical of the
position of determinists
(E) contrast the historical position of determinists
with their position regarding the exchange
modernization
524. Which of the following statements about Clark’s study
of the telephone exchange can be inferred from
information in the passage?
(A) Clark’s reason for undertaking the study was to
undermine Braverman’s analysis of the function
of technology.
(B) Clark’s study suggests that the implementation
of technology should be discussed in the context
of con ict between labor and management.
(C) Clark examined the impact of changes in the
technology of switching at the exchange in terms
of overall operations and organization.
(D) Clark concluded that the implementation of new
switching technology was equally bene cial to
management and labor.
(E) Clark’s analysis of the change in switching
systems applies only narrowly to the situation at
the particular exchange that he studied.
7.4 Reading Comprehension Practice Questions
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Because the framers of the United States
Constitution (written in 1787) believed that protecting
property rights relating to inventions would encourage
the new nation’s economic growth, they gave
Congress—the national legislature—a constitutional
mandate to grant patents for inventions. The resulting
patent system has served as a model for those in
other nations. Recently, however, scholars have
questioned whether the American system helped
achieve the framers’ goals. These scholars have
contended that from 1794 to roughly 1830, American
inventors were unable to enforce property rights
because judges were “antipatent” and routinely
invalidated patents for arbitrary reasons. This
argument is based partly on examination of court
decisions in cases where patent holders (“patentees”)
brought suit alleging infringement of their patent
rights. In the 1820s, for instance, 75 percent
of verdicts were decided against the patentee.
The proportion of verdicts for the patentee began to
increase in the 1830s, suggesting to these scholars
that judicial attitudes toward patent rights began
shifting then.
Not all patent disputes in the early nineteenth
century were litigated, however, and litigated
cases were not drawn randomly from the
population of disputes. Therefore the rate of
verdicts in favor of patentees cannot be used
by itself to gauge changes in judicial attitudes
or enforceability of patent rights. If early judicial
decisions were prejudiced against patentees, one
might expect that subsequent courts—allegedly
more supportive of patent rights—would reject
the former legal precedents. But pre‐1830
cases have been cited as frequently as later
decisions, and they continue to be cited today,
suggesting that the early decisions, many of
which clearly declared that patent rights were
a just recompense for inventive ingenuity,
provided a lasting foundation for patent law.
The proportion of judicial decisions in favor of
patentees began to increase during the 1830s
because of a change in the underlying population
of cases brought to trial. This change was partly
due to an 1836 revision to the patent system:
an examination procedure, still in use today, was
instituted in which each application is scrutinized
for its adherence to patent law. Previously,
patents were automatically granted upon payment
of a $30 fee.
Questions 525–529 refer to the passage.
525. The passage implies that which of the following was
a reason that the proportion of verdicts in favor of
patentees began to increase in the 1830s?
(A) Patent applications approved after 1836 were
more likely to adhere closely to patent law.
(B) Patent laws enacted during the 1830s better
de ned patent rights.
(C) Judges became less prejudiced against
patentees during the 1830s.
(D) After 1836, litigated cases became less
representative of the population of patent
disputes.
(E) The proportion of patent disputes brought to trial
began to increase after 1836.
526. The passage implies that the scholars mentioned in
line 8 would agree with which of the following criticisms
of the American patent system before 1830?
(A) Its de nition of property rights relating to
inventions was too vague to be useful.
(B) Its criteria for the granting of patents were not
clear.
(C) It made it excessively dif cult for inventors to
receive patents.
(D) It led to excessive numbers of patent‐
infringement suits.
(E) It failed to encourage national economic growth.
527. It can be inferred from the passage that the frequency
with which pre‐1830 cases have been cited in court
decisions is an indication that
(A) judicial support for patent rights was strongest in
the period before 1830
(B) judicial support for patent rights did not increase
after 1830
(C) courts have returned to judicial standards that
prevailed before 1830
(D) verdicts favoring patentees in patent‐infringement
suits did not increase after 1830
(E) judicial bias against patentees persisted after
1830
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528. It can be inferred from the passage that the author
and the scholars referred to in line 21 disagree about
which of the following aspects of the patents defended
in patent‐infringement suits before 1830?
(A) Whether the patents were granted for inventions
that were genuinely useful
(B) Whether the patents were actually relevant to the
growth of the United States economy
(C) Whether the patents were particularly likely to be
annulled by judges
(D) Whether the patents were routinely invalidated
for reasons that were arbitrary
(E) Whether the patents were vindicated at a
signi cantly lower rate than patents in later suits
529. The author of the passage cites which of the following
as evidence challenging the argument referred to in
lines 14–15 ?
(A) The proportion of cases that were decided
against patentees in the 1820s
(B) The total number of patent disputes that were
litigated from 1794 to 1830
(C) The fact that later courts drew upon the legal
precedents set in pre‐1830 patent cases
(D) The fact that the proportion of judicial decisions
in favor of patentees began to increase during
the 1830s
(E) The constitutional rationale for the 1836 revision
of the patent system
7.4 Reading Comprehension Practice Questions
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Jacob Burckhardt’s view that Renaissance
European women “stood on a footing of perfect
equality” with Renaissance men has been repeatedly
cited by feminist scholars as a prelude to their
presentation of rich historical evidence of women’s
inequality. In striking contrast to Burckhardt, Joan
Kelly in her famous 1977 essay, “Did Women Have
a Renaissance?” argued that the Renaissance was
a period of economic and social decline for women
relative both to Renaissance men and to medieval
women. Recently, however, a signi cant trend
among feminist scholars has entailed a rejection
of both Kelly’s dark vision of the Renaissance and
Burckhardt’s rosy one. Many recent works by these
scholars stress the ways in which differences
among Renaissance women—especially in terms
of social status and religion—work to complicate
the kinds of generalizations both Burckhardt and
Kelly made on the basis of their observations about
upper‐class Italian women.
The trend is also evident, however, in works
focusing on those middle‐ and upper‐class
European women whose ability to write gives them
disproportionate representation in the historical
record. Such women were, simply by virtue of
their literacy, members of a tiny minority of the
population, so it is risky to take their descriptions of
their experiences as typical of “female experience”
in any general sense. Tina Krontiris, for example, in
her fascinating study of six Renaissance women
writers, does tend at times to con ate “women” and
“women writers,” assuming that women’s gender,
irrespective of other social differences, including
literacy, allows us to view women as a homogeneous
social group and make that group an object of
analysis. Nonetheless, Krontiris makes a signi cant
contribution to the eld and is representative of
those authors who offer what might be called a
cautiously optimistic assessment of Renaissance
women’s achievements, although she also stresses
the social obstacles Renaissance women faced
when they sought to raise their “oppositional
voices.” Krontiris is concerned to show women
intentionally negotiating some power for themselves
(45)
(50)
(at least in the realm of public discourse) against
potentially constraining ideologies, but in her sober
and thoughtful concluding remarks, she suggests
that such verbal opposition to cultural stereotypes
was highly circumscribed; women seldom attacked
the basic assumptions in the ideologies that
oppressed them.
Questions 530–536 refer to the passage.
530. The author of the passage discusses Krontiris primarily
to provide an example of a writer who
(A) is highly critical of the writings of certain
Renaissance women
(B) supports Kelly’s view of women’s status during
the Renaissance
(C) has misinterpreted the works of certain
Renaissance women
(D) has rejected the views of both Burckhardt and
Kelly
(E) has studied Renaissance women in a wide variety
of social and religious contexts
531. According to the passage, Krontiris’s work differs from
that of the scholars mentioned in line 12 in which of
the following ways?
(A) Krontiris’s work stresses the achievements of
Renaissance women rather than the obstacles to
their success.
(B) Krontiris’s work is based on a reinterpretation of
the work of earlier scholars.
(C) Krontiris’s views are at odds with those of both
Kelly and Burkhardt.
(D) Krontiris’s work focuses on the place of women
in Renaissance society.
(E) Krontiris’s views are based exclusively on the
study of a privileged group of women.
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532. According to the passage, feminist scholars cite
Burckhardt’s view of Renaissance women primarily for
which of the following reasons?
(A) Burckhardt’s view forms the basis for most
arguments refuting Kelly’s point of view.
(B) Burckhardt’s view has been discredited by Kelly.
(C) Burckhardt’s view is one that many feminist
scholars wish to refute.
(D) Burckhardt’s work provides rich historical
evidence of inequality between Renaissance
women and men.
(E) Burckhardt’s work includes historical research
supporting the arguments of the feminist scholars.
533. It can be inferred that both Burckhardt and Kelly have
been criticized by the scholars mentioned in line 12for
which of the following?
(A) Assuming that women writers of the Renaissance
are representative of Renaissance women in
general
(B) Drawing conclusions that are based on the study
of an atypical group of women
(C) Failing to describe clearly the relationship
between social status and literacy among
Renaissance women
(D) Failing to acknowledge the role played by
Renaissance women in opposing cultural
stereotypes
(E) Failing to acknowledge the ways in which
social status affected the creative activities of
Renaissance women
534. The author of the passage suggests that Krontiris
incorrectly assumes that
(A) social differences among Renaissance women are
less important than the fact that they were women
(B) literacy among Renaissance women was more
prevalent than most scholars today acknowledge
(C) during the Renaissance, women were able to
successfully oppose cultural stereotypes relating
to gender
(D) Renaissance women did not face many dif cult
social obstacles relating to their gender
(E) in order to attain power, Renaissance women
attacked basic assumptions in the ideologies
that oppressed them
535. The last sentence in the passage serves primarily to
(A) suggest that Krontiris’s work is not
representative of recent trends among feminist
scholars
(B) undermine the argument that literate women
of the Renaissance sought to oppose social
constraints imposed on them
(C) show a way in which Krontiris’s work illustrates
a “cautiously optimistic” assessment of
Renaissance women’s achievements
(D) summarize Krontiris’s view of the effect of
literacy on the lives of upper‐ and middle‐class
Renaissance women
(E) illustrate the way in which Krontiris’s study differs
from the studies done by Burckhardt and Kelly
536. The author of the passage implies that the women
studied by Krontiris are unusual in which of the
following ways?
(A) They faced obstacles less formidable than those
faced by other Renaissance women.
(B) They have been seen by historians as more
interesting than other Renaissance women.
(C) They were more concerned about recording
history accurately than were other Renaissance
women.
(D) Their perceptions are more likely to be
accessible to historians than are those of most
other Renaissance women.
(E) Their concerns are likely to be of greater interest
to feminist scholars than are the ideas of most
other Renaissance women.
7.4 Reading Comprehension Practice Questions
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(10)
(15)
(20)
(25)
When asteroids collide, some collisions cause
an asteroid to spin faster; others slow it down. If
asteroids are all monoliths—single rocks—undergoing
random collisions, a graph of their rotation rates
should show a bell-shaped distribution with statistical
“tails” of very fast and very slow rotators. If asteroids
are rubble piles, however, the tail representing the
very fast rotators would be missing, because any
loose aggregate spinning faster than once every few
hours (depending on the asteroid’s bulk density)
would y apart. Researchers have discovered that
all but ve observed asteroids obey a strict limit on
rate of rotation. The exceptions are all smaller than
200 meters in diameter, with an abrupt cutoff for
asteroids larger than that.
The evident conclusion—that asteroids larger than
200meters across are multicomponent structures or
rubble piles—agrees with recent computer modeling
of collisions, which also nds a transition at that
diameter. A collision can blast a large asteroid to bits,
but after the collision those bits will usually move
slower than their mutual escape velocity. Over several
hours, gravity will reassemble all but the fastest
pieces into a rubble pile. Because collisions among
asteroids are relatively frequent, most large bodies
have already suffered this fate. Conversely, most
small asteroids should be monolithic, because impact
fragments easily escape their feeble gravity.
Questions 537–540 refer to the passage.
537. The passage implies which of the following about the
ve asteroids mentioned in line 12 ?
(A) Their rotation rates are approximately the same.
(B) They have undergone approximately the same
number of collisions.
(C) They are monoliths.
(D) They are composed of fragments that have
escaped the gravity of larger asteroids.
(E) They were detected only recently.
538. The discovery of which of the following would call into
question the conclusion mentioned in line 16 ?
(A) An asteroid 100 meters in diameter rotating at a
rate of once per week
(B) An asteroid 150 meters in diameter rotating at a
rate of 20times per hour
(C) An asteroid 250 meters in diameter rotating at a
rate of once per week
(D) An asteroid 500 meters in diameter rotating at a
rate of once per hour
(E) An asteroid 1,000 meters in diameter rotating at
a rate of once every 24 hours
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539. According to the passage, which of the following
is a prediction that is based on the strength of the
gravitational attraction of small asteroids?
(A) Small asteroids will be few in number.
(B) Small asteroids will be monoliths.
(C) Small asteroids will collide with other asteroids
very rarely.
(D) Most small asteroids will have very fast rotation
rates.
(E) Almost no small asteroids will have very slow
rotation rates.
540. The author of the passage mentions “escape velocity”
(see line 22) in order to help explain which of the
following?
(A) The tendency for asteroids to become smaller
rather than larger over time
(B) The speed with which impact fragments
reassemble when they do not escape an
asteroid’s gravitational attraction after a collision
(C) The frequency with which collisions among
asteroids occur
(D) The rotation rates of asteroids smaller than
200 meters in diameter
(E) The tendency for large asteroids to persist after
collisions
7.4 Reading Comprehension Practice Questions
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Line
(5)
(10)
(15)
(20)
(25)
(30)
Most attempts by physicists to send particles
faster than the speed of light involve a remarkable
phenomenon called quantum tunneling, in which
particles travel through solid barriers that appear
to be impenetrable. If you throw a ball at a wall,
you expect it to bounce back, not to pass straight
through it. Yet subatomic particles perform the
equivalent feat. Quantum theory says that there is a
distinct, albeit small, probability that such a particle
will tunnel its way through a barrier; the probability
declines exponentially as the thickness of the
barrier increases. Though the extreme rapidity of
quantum tunneling was noted as early as 1932,
not until 1955 was it hypothesized—by Wigner and
Eisenbud—that tunneling particles sometimes
travel faster than light. Their grounds were
calculations that suggested that the time it takes a
particle to tunnel through a barrier increases with
the thickness of the barrier until tunneling time
reaches a maximum; beyond that maximum,
tunneling time stays the same regardless of
barrier thickness. This would imply that once
maximum tunneling time is reached, tunneling
speed will increase without limit as barrier thickness
increases. Several recent experiments have
supported this hypothesis that tunneling particles
sometimes reach superluminal speed. According to
measurements performed by Raymond Chiao and
colleagues, for example, photons can pass through
an optical lter at 1.7 times the speed of light.
Questions 541–543 refer to the passage.
541. The author of the passage mentions calculations about
tunneling time and barrier thickness in order to
(A) suggest that tunneling time is unrelated to
barrier thickness
(B) explain the evidence by which Wigner and
Eisenbud discovered the phenomenon of
tunneling
(C) describe data recently challenged by Raymond
Chiao and colleagues
(D) question why particles engaged in quantum
tunneling rarely achieve extremely high speeds
(E) explain the basis for Wigner and Eisenbud’s
hypothesis
542. The passage implies that if tunneling time reached no
maximum in increasing with barrier thickness, then
(A) tunneling speed would increase with barrier
thickness
(B) tunneling speed would decline with barrier
thickness
(C) tunneling speed would vary with barrier thickness
(D) tunneling speed would not be expected to
increase without limit
(E) successful tunneling would occur even less
frequently than it does
543. Which of the following statements about the earliest
scienti c investigators of quantum tunneling can be
inferred from the passage?
(A) They found it dif cult to increase barrier
thickness continually.
(B) They anticipated the later results of Chiao and
his colleagues.
(C) They did not suppose that tunneling particles
could travel faster than light.
(D) They were unable to observe instances of
successful tunneling.
(E) They made use of photons to study the
phenomenon of tunneling.
423
405. B
406. B
407. D
408. A
409. D
410. D
411. B
412. B
413. C
414. C
415. D
416. C
417. A
418. C
419. C
420. C
421. E
422. A
423. C
424. B
425. B
426. A
427. D
428. E
429. A
430. A
431. C
432. B
433. D
434. A
435. C
436. D
437. B
438. B
439. C
440. B
441. E
442. B
443. B
444. B
445. A
446. D
447. E
448. D
449. A
450. C
451. B
452. D
453. B
454. E
455. C
456. C
457. E
458. A
459. D
460. A
461. C
462. A
463. B
464. D
465. E
466. C
467. A
468. E
469. A
470. D
471. D
472. D
473. B
474. B
475. C
476. C
477. E
478. D
479. D
480. B
481. C
482. B
483. E
484. D
485. E
486. B
487. D
488. C
489. C
490. E
491. A
492. B
493. D
494. E
495. E
496. D
497. B
498. C
499. D
500. A
501. C
502. D
503. A
504. A
505. D
506. E
507. D
508. B
509. C
510. A
511. C
512. B
513. D
514. D
515. E
516. B
517. C
518. C
519. B
520. A
521. B
522. D
523. A
524. C
525. A
526. E
527. B
528. D
528. C
530. D
531. E
532. C
533. B
534. A
535. C
536. D
537. C
538. D
539. B
540. E
541. E
542. D
543. C
7.5 Answer Key
7.5 Reading Comprehension Answer Key
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GMAT® Offi cial Guide 2018
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Questions 405–408 refer to the passage on page 362.
405. According to the passage, theory B states that which
of the following is a factor that enables a schooling sh
to escape predators?
(A) The tendency of sh to form compact groups
(B) The movement of other sh within the school
(C) The inability of predators to detect schools
(D) The ability of sh to hide behind one another in
aschool
(E) The great speed with which a school can disperse
Supporting idea
is question depends on understanding what
the passage states about theory B, the “confusion
e ect.” One element of theory B is that predators
may experience sensory confusion created by large
numbers of moving sh in a school.
A e compactness of groups of schooling sh
is an element of theory A, not theory B.
B Correct. It is the movement of schooling
sh around a predator that creates sensory
confusion in the predator; this movement
may distract the predator and help protect
individual sh in the school.
C According to the passage’s description of
theory A, predators are actually slightly
more likely to detect schools than they are
to detect individual sh.
D eory B does not involve sh hiding
behind one another but rather moving
around the predator.
E e passage does not discuss the speed of
dispersal of schools of sh.
e correct answer is B.
406. According to the passage, both theory A and theory B
have been developed to explain how
(A) sh hide from predators by forming schools
(B) forming schools functions to protect sh from
predators
(C) schooling among sh differs from other
protective behaviors
(D) small sh are able to make rapid decisions
(E) small sh are able to survive in an environment
densely populated by large predators
Supporting idea
e passage states in its rst paragraph that two
theories were developed to explain why schooling
occurs in so many sh species and that they both
assume that schooling helps protect sh from
predators.
A While theory A involves an explanation of
how schooling makes an individual sh less
likely to be found by predators, theory B
explains how schooling protects sh even
when they are detected by predators.
B Correct. Both theory A and theory B begin
with the assumption that schooling provides
protection from predators, and each theory
o ers a di erent explanation for how that
protection occurs.
C e passage does not discuss protective
behaviors other than schooling.
D e decision‐making ability of predators, not
schooling sh, is discussed in the passage;
schooling is presented as an instinctive behavior.
E e passage suggests that only theory B helps
explain schooling behavior in environments
where many predators, large or otherwise, are
found, and that theory A explains schooling
in areas where predators are not as abundant.
e correct answer is B.
7.6 Answer Explanations
The following discussion of reading comprehension is intended to familiarize you with the most efficient
and effective approaches to the kinds of problems common to reading comprehension. The particular
questions in this chapter are generally representative of the kinds of reading comprehension questions
you will encounter on the GMAT exam. Remember that it is the problem solving strategy that is
important, not the specific details of a particular question.
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407. According to one explanation of the “confusion
effect,” a sh that swims in a school will have greater
advantages for survival if it
(A) tends to be visible for no more than 200 meters
(B) stays near either the front or the rear of a school
(C) is part of a small school rather than a large
school
(D) is very similar in appearance to the other sh in
the school
(E) is medium‐sized
Inference
e “confusion e ect” is discussed in the third
and fourth paragraphs. e rst explanation
of the “confusion e ect” proposes that because
predators prefer to select distinctive prey, they
nd it di cult to select one sh from among
many that look the same.
A e 200‐meter visibility of sh is part of the
explanation for theory A, not theory B (the
“confusion e ect”).
B e location of an individual sh within
a school is not discussed in the passage as
being important to the “confusion e ect.”
C e size of a school of sh is not discussed
as an element of the “confusion e ect.”
D Correct. Because predators, according to
the “confusion e ect,” prefer to select prey
that is distinct from the rest of the school,
a sh that is similar in appearance to the
other sh in its school would most likely
enjoy a survival advantage.
E e size of a sh relative to the other sh in
its school would most likely contribute to
its ability to survive: that is, if it resembled
other sh in size, it would be safer, based on
what the passage says about the “confusion
e ect.” Furthermore, the passage gives no
reason to think that merely being medium‐
sized would confer any advantage (unless
the other sh were medium‐sized as well).
e correct answer is D.
408. The author is primarily concerned with
(A) discussing different theories
(B) analyzing different techniques
(C) defending two hypotheses
(D) refuting established beliefs
(E) revealing new evidence
Main idea
Determining the author’s primary concern
depends on understanding the focus of the
passage as a whole. e author presents two
theories that purport to account for why sh,
particularly small sh, tend to school and explains
the arguments of proponents of each theory.
A Correct. e author discusses two
theories—identi ed as theory A and
theoryB—that account for the tendency of
sh to school.
B e author is not concerned with di erent
techniques in the passage.
C e two theories of why sh school could
be referred to as hypotheses, but the author
is not primarily concerned with defending
them; rather, the passage explains how each
attempts to account for the phenomenon in
question.
D e author presents, rather than refutes,
beliefs about why sh tend to school.
E e author reveals no evidence, new or
otherwise, in the passage. e passage is
a general discussion of scienti c opinions
based on existing evidence.
e correct answer is A.
7.6 Reading Comprehension Answer Explanations
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Questions 409–411 refer to the passage on page 364.
409. The primary purpose of the passage is to
(A) challenge recent ndings that appear to
contradict earlier ndings
(B) present two sides of an ongoing scienti c debate
(C) report answers to several questions that have
long puzzled researchers
(D) discuss evidence that has caused a long‐
standing belief to be revised
(E) attempt to explain a commonly misunderstood
biological phenomenon
Main idea
is question depends on understanding the
passage as a whole. e passage begins by
describing a long‐held belief regarding humans’
circadian rhythms: that the SCNs control them.
It then goes on to explain that new ndings have
led scientists to believe that other organs and
tissues may be involved in regulating the body’s
circadian rhythms as well.
A e passage does not challenge the more‐
recent ndings. Furthermore, the recent
ndings that the passage recounts do not
contradict earlier ndings; rather, when
placed alongside those earlier ndings,
they have led scientists to reach additional
conclusions.
B e passage does not discuss a two‐sided
debate; no ndings or conclusions are
disputed by any gures in the passages.
C ere is only one question at issue in the
passage: whether the SCN alone control
human circadian rhythms. Furthermore,
nothing in the passage suggests that
researchers have been puzzled for a long
time about this.
D Correct. e new evidence regarding
circadian rhythm–related gene activity in all
the body’s tissue has led scientists to revise
their long‐standing belief that the SCN
alone control circadian rhythms.
E e biological phenomenon of circadian
rhythms is not, at least as far as the passage
is concerned, misunderstood. Its causes are
being investigated and re ned.
e correct answer is D.
410. The passage mentions each of the following as a
function regulated by the SCNs in some animals
EXCEPT
(A) activity level
(B) blood pressure
(C) alertness
(D) vision
(E) temperature
Supporting idea
is question asks about what is NOT speci cally
mentioned in the passage with regard to
functions regulated by the SCN. ose functions,
as identi ed in the passage, are blood pressure,
body temperature, activity level, alertness, and the
release of melatonin.
A e passage includes activity level in its list
of functions regulated by the SCN.
B e passage includes blood pressure in its
list of functions regulated by the SCN.
C e passage includes alertness in its list of
functions regulated by the SCN.
D Correct. While the passage does say
that cells in the human retina transmit
information to the SCN, there is no
suggestion that the SCN reciprocally
control vision.
E e passage includes temperature in its list
of functions regulated by the SCN.
e correct answer is D.
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427
411. The author of the passage would probably agree with
which of the following statements about the SCNs?
(A) The SCNs are found in other organs and tissues
of the body besides the hypothalamus.
(B) The SCNs play a critical but not exclusive role in
regulating circadian rhythms.
(C) The SCNs control clock genes in a number of
tissues and organs throughout the body.
(D) The SCNs are a less signi cant factor in
regulating blood pressure than scientists once
believed.
(E) The SCNs are less strongly affected by changes
in light levels than they are by other external
cues.
Main idea
e author of the passage discusses the SCN in
the passage in order to explain that they are most
likely not, as long believed, solely responsible for
the control of our circadian rhythms.
A e author states that the SCN are nerve
clusters in the hypothalamus, and nothing
in the passage contradicts or undermines
the supposition that they are only in the
hypothalamus.
B Correct. e author points out in the
second paragraph that the SCN control core
circadian function, but that circadian clocks
found elsewhere in the body have an e ect
as well.
C e evidence o ered in the second
paragraph about the activity of the clock
gene in rat livers suggests that these clock
genes are not under the SCN’s control. e
passage does not suggest that the SCN
control any of the non‐SCN controllers of
circadian rhythms.
D e author states in the second paragraph
that scientists do not dispute the idea that
the SCN regulate blood pressure.
E e rst paragraph indicates that the SCN
respond to light levels; clock genes in other
tissues are the ones that may respond to
other external cues.
e correct answer is B.
Questions 412–414 refer to the passage on page 366.
412. The primary purpose of the passage is to
(A) question the results of a study that examined
the effect of service-quality guarantees in the
restaurant industry
(B) discuss potential advantages and disadvantages
of service-quality guarantees in the restaurant
industry
(C) examine the conventional wisdom regarding
the effect of service-quality guarantees in the
restaurant industry
(D) argue that only certain restaurants would bene t
from the implementation of service-quality
guarantees
(E) consider the impact that service-quality
guarantees can have on the service provided by
a restaurant
Main idea
is question depends on understanding the
passage as a whole. e rst paragraph describes
Tucci and Talaga’s ndings regarding the e ect
of service-quality guarantees: that they have
di erent, more positive results for higher-
priced restaurants than for lower-priced ones,
which could be a ected negatively. e second
paragraph explains that a particular bene t from
service guarantees could accrue to restaurants
generally.
A e passage does not question the results of
Tucci and Talaga’s study; rather, the passage
appears to accept the results of the study as
accurate.
B Correct. e potential advantages involve
the management and motivation of
service sta , as well as, for higher-priced
restaurants, a greater likelihood of being
selected by customers over other restaurants.
Potential disadvantages for lower-priced
restaurants include the possibility that
potential customers may believe that such
restaurants are concerned about the quality
of their service.
7.6 Reading Comprehension Answer Explanations
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C e passage does not indicate whether
there is any conventional wisdom regarding
service-quality guarantees in the restaurant
industry.
D e second paragraph of the passage
suggests that restaurants in general could
potentially enjoy some bene ts from
the implementation of service-quality
guarantees. For lower-priced restaurants,
these bene ts could o set the possible
negative e ects of service-quality guarantees
described in the rst paragraph.
E e second paragraph of the passage
indicates an e ect that service-quality
guarantees could have on a restaurant’s sta
and the service that the sta provides, but
this is only one of the subsidiary points
contributing to the focus of the passage as
a whole. e rst is more concerned with
the question of what e ect these guarantees
would have on whether customers choose to
patronize that restaurant.
e correct answer is B.
413. It can be inferred that the author of the passage would
agree with which of the following statements about the
appeal of service guarantees to customers?
(A) Such guarantees are likely to be somewhat more
appealing to customers of restaurants than to
customers of other businesses.
(B) Such guarantees are likely to be more appealing
to customers who know what to anticipate in
terms of service.
(C) Such guarantees are likely to have less appeal in
situations where customers are knowledgeable
about a business’s product or service.
(D) In situations where a high level of nancial
commitment is involved, a service guarantee is
not likely to be very appealing.
(E) In situations where customers expect a high
level of customer service, a service guarantee is
likely to make customers think that a business is
worried about its service.
Inference
is question asks for an inference from the
passage about the author’s view of why and how
service guarantees would appeal to customers.
e question does not ask speci cally about
service guarantees in the context of restaurants,
but rather service guarantees in general. e
end of the rst paragraph addresses this general
question: a service guarantee may appeal most to
customers in the case of activities whose quality
they are less likely to know how to question.
A e author states that a service guarantee
might have greater appeal in the case of
skilled activities than it would for restaurant
customers.
B According to the author, customers who
know what to expect in terms of service—a
group that includes restaurant customers—
would likely nd service guarantees less
appealing.
C Correct. e author makes clear that service
guarantees would be less appealing to
restaurant customers when they know what
to expect in terms of the quality of service.
D e passage provides some evidence that
where a high level of nancial commitment
is involved, a service guarantee may be
more rather than less appealing than in
other situations. In discussing higher-priced
restaurants, which require a relatively high
level of nancial commitment, the author
states that Tucci and Talaga found evidence
that a service guarantee would likely appeal
to customers.
E e author implies that customers of
higher-priced restaurants expect a high
level of service, certainly a level higher
than that expected by customers of lower-
priced restaurants. But it is at lower-priced
restaurants that Tucci and Talaga found that
a service guarantee makes customers think
a given restaurant is concerned about its
service.
e correct answer is C.
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429
414. According to the passage, Tucci and Talaga found
that service guarantees, when offered by lower-priced
restaurants, can have which of the following effects?
(A) Customers’ developing unreasonably high
expectations regarding service
(B) Customers’ avoiding such restaurants because
they fear that the service guarantee may not be
fully honored
(C) Customers’ interpreting the service guarantee as
a sign that management is not con dent about
the quality of its service
(D) A restaurant’s becoming concerned that its service
will not be assiduous enough to satisfy customers
(E) A restaurant’s becoming concerned that
customers will be more emboldened to question
the quality of the service they receive
Supporting ideas
is question requires identifying Tucci and
Talaga’s ndings regarding service guarantees
o ered by lower-priced restaurants. e passage
states directly that these researchers found in
these situations that a guarantee could lead
potential customers to think that the restaurant
has concerns about its service.
A e passage does not report that Tucci and
Talaga found that service guarantees create
unreasonably high expectations regarding
service.
B e passage does not report that Tucci and
Talaga found that customers doubted that
service guarantees would be honored.
C Correct. e passage explicitly indicates
that Tucci and Talaga found that potential
customers of lower-priced restaurants could
interpret service guarantees as indicating
worries about the quality of service.
D e passage indicates that Tucci and Talaga
found that customers might think that
lower-priced restaurants are o ering service
guarantees because they are concerned that
the quality of their service is too low, but
the passage does not indicate that service
guarantees lead such restaurants to have
concerns about the quality of their service,
and in fact it may be that such guarantees
could lead to improvements in service.
E e passage indicates that service guarantees
o ered at lower-priced restaurants may
empower customers to question the quality
of service, but it does not indicate that
service guarantees lead restaurants to have
concerns about this.
e correct answer is C.
Questions 415–418 refer to the passage on page 368.
415. Information in the passage suggests that David Pearce
would most readily endorse which of the following
statements concerning monetization?
(A) Monetization represents a strategy that is
attractive to both environmentalists and their
critics.
(B) Monetization is an untested strategy,
but it is increasingly being embraced by
environmentalists.
(C) Monetization should at present be restricted to
ecological services and should only gradually
be extended to such commercial endeavors as
tourism and recreation.
(D) Monetization can serve as a means of
representing persuasively the value of
environmental conservation.
(E) Monetization should inform environmental
decision-making processes only if it is accepted
by environmentalist groups.
Inference
is question requires an understanding of David
Pearce’s view of monetization. According to the
passage, Pearce nds the idea that conservation
is unpro table to be an illusion. He argues for
showing the economic value of ecosystems in
order to make progress in conserving those
ecosystems.
A e passage attributes to Gretchen Daily
the view that monetization is unpopular
with environmentalists. e passage gives no
reason to believe that Pearce would endorse
the idea that environmentalists currently
nd monetization attractive.
7.6 Reading Comprehension Answer Explanations
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B e passage gives no indication that
monetization is increasingly being embraced
by environmentalists, even if Pearce thinks it
should be.
C e passage indicates Pearce’s belief that
some types of tourism are also types of
ecological services that have economic value
and that they should be monetized.
D Correct. Pearce believes that monetization
quanti es the value of the services provided
by ecological systems—and if that value
is quanti ed, people are more likely to be
persuaded to conserve those systems.
E Pearce is arguing, against some
environmentalists, that monetization should
inform the decision-making process with
regard to preserving ecosystems.
e correct answer is D.
416. Which of the following most clearly represents an
example of an “ecological service” as that term is used
in line 20 ?
(A) A resort hotel located in an area noted for its
natural beauty
(B) A water-purifying plant that supplements natural
processes with nontoxic chemicals
(C) A wildlife preserve that draws many international
travelers
(D) A nonpro t rm that specializes in restoring
previously damaged ecosystems
(E) A newsletter that keeps readers informed of
ecological victories and setbacks
Application
Based on the passage, ecological services are
services provided by natural assets that have not
been converted into commercial assets. us any
example of such an ecological service requires
that the area providing it is natural.
A e passage mentions resort hotels as an
example of explicitly commercial assets.
Although some hotels might be situated in
ecologically valuable natural environments,
any ecological services in such cases would
be contributed by the natural environments,
not by the hotels themselves.
B Water purifying is an ecological service if
it is supplied by undisturbed forests and
wetlands. e word plant here must mean
a technological installation, not a botanical
organism, because it is said to supplement—
not to be part of—the natural processes.
us it is not a natural asset and therefore
does not provide an ecological service as
described in the passage.
C Correct. e passage states that a wildlife
preserve that creates jobs and generates
income would be providing an ecological
service.
D A nonpro t rm that restores damaged
ecosystems would be performing a valuable
ecology-related service, but it would not
itself be an example of a natural asset
providing an ecological service.
E Environmentalists and others would most
likely nd such a newsletter informative,
but it would not be an ecological service,
because it is not a service provided by a
natural asset.
e correct answer is C.
417. According to the passage, Daily sees monetization as
an indication of which of the following?
(A) The centrality of economic interests to people’s
actions
(B) The reluctance of the critics of environmentalism
to acknowledge the importance of conservation
(C) The inability of nancial interests and ecological
interests to reach a common ideological ground
(D) The inevitability of environmental degradation
(E) The inevitability of the growth of ecological
services in the future
Supporting ideas
is question asks about Daily’s view of
monetization, and according to the passage, she
sees monetization as a practice that re ects the
dominant role that economic decisions play in human
behavior.
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431
A Correct. According to the passage, Daily
believes that economic interests are central
to people’s actions, and monetization of
ecological services would take that central
role realistically into account.
B Monetization, as Daily sees it, is a way of
assigning value to conservation and thus
acknowledging its importance. Many
environmentalists, rather than their critics,
are reluctant to embrace monetization,
according to Daily.
C For Daily, monetization represents a way for
nancial interests and ecological interests
to reach a common ground; by using this
common currency, both sides can make good
decisions about the environment.
D Monetization, on Daily’s view, would help
to prevent environmental degradation; the
passage does not suggest that she regards
such degradation as at all inevitable.
E Daily does not see monetization as
inevitably spurring the growth of ecological
services but as more likely preventing
their decline by leaving those services
undisturbed.
e correct answer is A.
418. Which of the following can be inferred from the
passage concerning the environmentalists mentioned
in line 8 ?
(A) They are organized in opposition to the
generation of income produced by the sale of
ecological services.
(B) They are fewer in number but better organized
and better connected to the media than their
opponents.
(C) They have sometimes been charged with failing
to use a particular strategy in their pursuit of
conservational goals.
(D) They have been in the forefront of publicizing the
extent of worldwide environmental degradation.
(E) They de ne environmental progress differently
and more conservatively than do other organized
groups of environmentalists.
Inference
e sentence in question states that critics blame
environmentalists for their failure to address the
economic issues of environmental degradation.
A e passage states that in the absence of
monetization, conservation can appear
unpro table. But this does not mean that
the environmentalists in question are
opposed to conservation generating income.
B e passage does not address the issue
of the number of environmentalists in
question, the number of those opposed
to them, or whether either group is better
connected to the media.
C Correct. e passage indicates that critics
of the environmentalists in question believe
environmentalists are to blame for not using
an e ective economics-based strategy to
promote conservation.
D Although it may be the case that the
environmentalists in question have been
prominent in publicizing worldwide
environmental degradation, the passage does
not provide grounds for inferring that they
have been.
E e passage suggests that certain critics
consider environmentalists in general to
be at fault for failing to address economic
issues. In this respect, the passage
makes no distinctions among di erent
environmentalist groups, organized or
otherwise.
e correct answer is C.
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
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Questions 419–422 refer to the passage on page 370.
419. According to the passage, the studies referred to in
line 12 reported which of the following about the effect
of price on consumers’ perception of the performance
risk associated with a new product?
(A) Although most consumers regard price as
an important factor, their perception of the
performance risk associated with a new product
is ultimately determined by the manufacturer’s
reputation.
(B) Price interacts with the presentation of an
advertised message to affect perceived
performance risk.
(C) Price does not signi cantly affect consumers’
perception of the performance risk associated
with a new product.
(D) Consumers tend to regard price as more
important than the manufacturer’s credibility
when they are buying from that manufacturer for
the rst time.
(E) Consumers are generally less concerned about
a new product’s performance risk when that
product is relatively expensive.
Supporting ideas
e question asks about information explicitly
provided in the passage. e rst paragraph
explains that there are con icting ndings in the
research about how the price of a product a ects
a consumer’s perception of the performance risk
of that product. Some studies have found that
higher priced products reduce the perception
of performance risk. e other studies referred
to in line 12, however, have found little or
no connection between price and perceived
performance risk.
A e passage does not mention that these
studies consider the manufacturer’s
reputation.
B e passage does not mention that these
studies consider advertising messages.
C Correct . e passage indicates that these
studies have found little or no connection
between relative price and consumers’
perception of performance risk.
D e passage does not mention that these
studies consider the manufacturer’s
credibility.
E Although some studies have found that a
relatively high price reduces the perception
of performance risk, the passage explains
that the studies referred to in line 12 have
not con rmed that nding.
e correct answer is C.
420. The “past research” mentioned in line 25 suggests
which of the following about perceived performance
risk?
(A) The more expensive a new product is, the more
likely consumers may be to credit advertised
claims about that product.
(B) The more familiar consumers are with a
particular manufacturer, the more willing they
may be to assume some risk in the purchase
of a new product being advertised by that
manufacturer.
(C) Consumers’ perception of the performance risk
associated with a new product being advertised
may be in uenced by an interplay between the
product’s price and the manufacturer’s credibility.
(D) Consumers may be more likely to believe that
a product will function as it is advertised to
do when they have bought products from a
particular manufacturer before.
(E) The price of a particular advertised product
may have less impact than the manufacturer’s
credibility on consumers’ assessment of the
performance risk associated with that product.
Supporting ideas
e question asks about information explicitly
provided in the passage. e second paragraph
explains that, according to some research,
consumers perceive a product as having less
performance risk when they trust the source
of advertising about that product. Past research ,
however, suggests that performance risk is
a ected not merely by the credibility of the
source, but by an interaction between source
credibility and the price of the product.
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433
A e passage does not indicate that the past
research addressed the question of how
the price of a product a ects consumers’
perception of advertised claims. It only
says that the research suggests that the two
factors interact .
B Although the passage discusses consumers’
perception of how risky a purchase might
be, it does not address the relationship
between familiarity and willingness to
assume risk.
C Correct. e past research suggests
that performance risk is a ected by an
interaction between the price of the product
and the credibility of the source of the
advertising about the product—in other
words, the manufacturer.
D e past research suggests that consumers’
beliefs about a product’s performance are
a ected not merely by their perception
of the manufacturer, but by an interplay
between source credibility and product price.
e passage does not mention any possible
role of prior experience in this interplay.
E e passage does not discuss whether
price or the manufacturer’s credibility
has more of an e ect on perceived
performance risk.
e correct answer is C.
421. The passage is primarily concerned with
(A) challenging the implications of previous research
into why consumers try new products
(B) suggesting new marketing strategies for
attracting consumers to new products
(C) reconciling two different views about the effect
of price on consumers’ willingness to try new
products
(D) describing a new approach to researching why
consumers try new products
(E) discussing certain ndings regarding why
consumers try new products
Main idea
The question depends on understanding the
passage as a whole. The passage begins with
a statement explaining that much research
has investigated what motivates consumers
to try new products . It then defines one such
motivating factor—perception of performance
risk. The remainder of the passage summarizes
research into how price and a manufacturer’s
advertising affect consumers’ perception of
performance risk.
A e passage summarizes research ndings
that con ict with one another but does not
support some ndings over others.
B e passage does not suggest any new
marketing strategies.
C e rst paragraph mentions a study that
could reconcile two con icting ndings, but
this is only a supporting point in the passage’s
larger purpose of summarizing research.
D e passage does not describe new research
approaches.
E Correct . e passage discusses studies about
performance risk, which is a factor that
motivates consumers to try new products.
e correct answer is E.
422. Which of the following, if true, would most tend to
weaken the conclusions drawn from “some of this
research” (see line 8)?
(A) In a subsequent study, consumers who were
asked to evaluate new products with relatively
low prices had the same perception of the
products’ performance risk as did consumers
who were shown the same products priced more
expensively.
(B) In a subsequent study, the quality of the
advertising for the products that consumers
perceived as having a lower performance risk
was relatively high, while the quality of the
advertising for the products that consumers
perceived as having a higher performance risk
was relatively poor.
(C) In a subsequent study, the products that
consumers perceived as having a lower
performance risk were priced higher than the
highest priced products in the previous research.
7.6 Reading Comprehension Answer Explanations
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(D) None of the consumers involved in this research
had ever before bought products from the
manufacturers involved in the research.
(E) Researchers found that the higher the source
credibility for a product, the more consumers
were willing to pay for it.
Evaluation
e question depends on evaluating the
reasoning behind the conclusions of some
research and deciding which evidence would
weaken them. e research concludes that
higher prices reduce consumers’ perception of
performance risk associated with a particular
product. is conclusion involves a claim of
cause and e ect, so evidence showing that
higher prices do not cause that e ect would
weaken the argument.
A Correct. If lowering prices has no e ect on
consumers’ perception of performance risk,
the conclusions of the research are called
into question.
B A correlation between quality of advertising
and perceived performance risk is not
clearly relevant to the research conclusions
about the e ects of price.
C is answer choice provides no basis for
comparison among prices within the
subsequent study. For all we can tell, the
prices that correlated with higher perceived
performance risk in the subsequent study
may have been lower than those that
correlated with lower perceived risk. In that
case, the subsequent study would tend to
strengthen, not weaken, the conclusions
drawn from the earlier research.
D Consumers’ lack of familiarity with other
products from the manufacturers is not
clearly relevant to the studies’ conclusions
about the e ects of price.
E Credibility of the source of advertisements
is discussed as a separate issue in the second
paragraph and is not clearly relevant to
these studies’ conclusions about the e ects
of price. To the extent that it may be
obliquely relevant, it tends to strengthen,
rather than to weaken, the conclusions.
e correct answer is A.
Questions 423–427 refer to the passage on page 372.
423. The primary purpose of the passage is to
(A) compare the economic role played by southern
banks with the economic role played by banks
in the rest of the United States during the late
eighteenth and early nineteenth centuries
(B) reevaluate a conventional interpretation of the role
played by banks in the American economy during
the late eighteenth and early nineteenth centuries
(C) present different interpretations of the role
played by banks in the American economy during
the late eighteenth and early nineteenth centuries
(D) analyze how the increasing number of banks in
the late eighteenth and early nineteenth centuries
affected the American economy
(E) examine how scholarly opinion regarding the role
played by banks in the American economy during
the late eighteenth and early nineteenth centuries
has changed over time
Main idea
e question depends on understanding the passage
as a whole. e passage describes two contrasting
views about the role banks played in the economic
growth of the United States around the turn of the
nineteenth century. e rst paragraph describes the
view that banks played only a small role. e second
paragraph describes the contrasting view that banks
played a critical role.
A e mention of banks in the South is a
small part of a larger discussion about the
role of banks in the country as a whole.
B e passage describes two major views held
by historians; it does not reevaluate either of
those views.
C Correct . e passage describes two di erent
views about the role that banks played in
America’s growing economy.
D e passage does not analyze any aspect
of the relationship between the increasing
number of banks and the economy. It alludes
to the increase in numbers only within a
broader description of two contrasting views
about how banks a ected the economy.
E e passage suggests that at the time when
it was written, the two views it describes
were both still held among historians.
e correct answer is C.
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435
424. The passage suggests that the scholars mentioned in
line 4 would argue that the reason banks tended not to
fund manufacturing and transportation projects in the
late eighteenth and early nineteenth centuries was that
(A) these projects, being well established and well
capitalized, did not need substantial long‐term
nancing from banks
(B) these projects entailed a level of risk that was too
great for banks’ conservative lending practices
(C) banks preferred to invest in other, more
speculative projects that offered the potential for
higher returns
(D) bank managers believed that these projects
would be unlikely to contribute signi cantly to
economic growth in the new country
(E) bank managers believed funding these projects
would result in credit being extended to too
many borrowers
Inference
e question asks about information implied by the
passage. According to the scholars’ view described
in the rst paragraph, banks followed conservative
lending practices: they shunned projects that were
uncertain and that required substantial investments
in capital. It follows that, according to those
scholars, the reason banks chose not to fund certain
projects was that they entailed too great a risk.
A e passage indicates that manufacturing
and transportation projects were less well
established than those the banks preferred
to fund, not more so.
B Correct. Because the projects were
uncertain and required a great deal of capital,
banks considered them too risky.
C e passage indicates that banks followed
conservative lending practices and avoided
investments that were uncertain.
D e passage does not mention banks’ beliefs
about economic growth, and it does not
provide any basis for inferring that the
scholars in question held any particular
views regarding such beliefs.
E e passage does not mention, or provide a
basis for inferences about, bank managers’
concerns about numbers of borrowers.
e correct answer is B.
425. The passage suggests that Paul Gilje would be most
likely to agree with which of the following claims about
the lending practices of the “earliest banks” (see
line 21) ?
(A) These lending practices were unlikely to
generate substantial pro ts for banks.
(B) These lending practices only bene ted a narrow
sector of the economy.
(C) The restrictive nature of these lending practices
generated signi cant opposition outside of the
South.
(D) The restrictive nature of these lending
practices forced state legislatures to begin
granting more bank charters by the early
nineteenth century.
(E) These lending practices were likely to be
criticized by economic elites as being overly
restrictive.
Inference
is question asks about conclusions that can
be logically inferred from information provided
in the passage. According to the second
paragraph, Paul Gilje believes that a driving
force in American economic growth in the
early nineteenth century was banks’ lending to a
larger and more diverse group of borrowers. e
question asks what this would imply about Gilje’s
view toward earlier banks—which, the passage
explains, o ered credit only to well‐connected
merchants .
A e pro tability of banks’ lending practices
is not at issue in the discussion.
B Correct . e passage says that the earliest
banks had primarily made loans only
to a narrow sector—well‐connected
merchants—and that they began lending
more broadly in the early nineteenth
century. It then cites Gilje’s view to
corroborate and explicate this claim. is
strongly suggests that Gilje agrees with the
claim.
C Opposition to the earliest banks is not
mentioned or alluded to in the discussion.
D e passage provides no basis for inferring
that Gilje held any particular view as to
why legislatures began granting more bank
charters.
7.6 Reading Comprehension Answer Explanations
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E e passage does not mention or provide a
basis for inference about the views of economic
elites regarding the lending practices of the
earliest banks in the United States. It thus
provides no basis for inferring that Gilje would
have any particular opinion on this topic.
e correct answer is B.
426. The passage suggests that the opposition to banks in
the South in the early nineteenth century stemmed in
part from the perception that banks
(A) did not bene t more than a small minority of the
people
(B) did not support the interests of elite planters
(C) were too closely tied to transportation and
industrial interests
(D) were unwilling to issue the long‐term loans
required by agrarian interests
(E) were too willing to lend credit widely
Inference
e question asks about statements that can
be inferred from information provided in the
passage. e second paragraph explains that people
who opposed banks in the South saw them as
monopolies controlled by elite planters. is would
imply that those who opposed banks believed that
most people in the South did not bene t from them.
A Correct. Since people opposed the banks
on the grounds that they were monopolies
controlled by an elite group of planters, they
likely thought banks did not bene t most of
the population.
B e passage implies that people believed the
banks did serve the interests of elite planters.
C e passage indicates that people believed
banks in the South were tied to planters, not
to transportation and industrial interests.
D Southern banks’ willingness to provide long‐
term loans is not discussed or alluded to in
the passage.
E e passage does not imply that anyone
believed banks in the South were willing to
lend credit widely. Since people believed the
banks were controlled by the elite, they more
likely thought banks were unwilling to lend
credit widely.
e correct answer is A.
427. Which of the following statements best describes the
function of the last sentence of the passage?
(A) It provides evidence tending to undermine the
viewpoint of the scholars mentioned in line 5.
(B) It resolves a con ict over the role of banks
summarized in the rst paragraph.
(C) It clari es some of the reasons state legislatures
began granting more bank charters.
(D) It quali es a claim made earlier in the passage
about the impact of banks on the American
economy in the early nineteenth century.
(E) It supports a claim made earlier in the passage
about how the expansion of credit affected the
economy.
Evaluation
is question asks about the function of the last
sentence in relation to the rest of the passage.
e rst paragraph describes the view of one set
of historians. e second paragraph describes the
contrasting view of a second set of historians.
e last sentence of the passage points out
an exception mentioned by the second set of
historians.
A e last sentence pertains to the view
of historians described in the second
paragraph, not those described in the rst
paragraph.
B e con ict between the two di ering views
is not resolved by the passage.
C e passage does not explain why
legislatures began granting more bank
charters.
D Correct . e second set of historians claim
banks spurred American economic growth
at the turn of the nineteenth century, but
the last sentence adds an exception to that
claim.
E e last sentence does not support the claim
made by the second set of historians, but
rather serves as an exception to that claim.
e correct answer is D.
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Questions 428–430 refer to the passage on page 374.
428. According to the passage, the difference in the amount
of cratering on Callisto’s and Io’s respective surfaces
can probably be explained by the difference between
these two moons with respect to which of the following
factors?
(A) Size
(B) Ice content
(C) The rate of bombardment by comets and
asteroids
(D) The in uence of Jupiter’s other moons
(E) The level of geological activity
Supporting idea
Cratering is discussed in the second paragraph.
e passage states that Callisto is heavily cratered,
while Io has no detectable craters. Io is the moon
closest to Jupiter, and Callisto is the farthest
away. eir relative positions are accompanied by
a corresponding di erence in geological activity:
Io is very geologically active, while Callisto is not
active at all. Io’s geological activity means that it
is being regularly resurfaced, so it is unlikely to
retain any evidence of cratering—unlike Callisto,
which experiences no resurfacing, leaving its
craters intact.
A While the passage makes clear that Callisto
is larger than Io, it does not address whether
their relative size explains the di erence in
their respective amounts of cratering.
B According to the passage, Callisto and
Io di er in terms of their ice content,
but nothing in the passage indicates that
that content a ects the cratering on their
surfaces.
C e passage states that Io experiences a
higher rate of bombardment than Callisto
does, but while that bombardment most
likely causes cratering on Io, its surface does
not retain those craters. us, the rate of
bombardment does not, in itself, explain the
di erence in cratering on the surface of the
two moons.
D e only other moons of Jupiter discussed
inthe passage are Ganymede and Europa,
and the passage does not consider their
e ect on the cratering of Callisto and Io.
E Correct. Because Io experiences a high
degree of geological activity, its surface is
continuously resurfaced, which means that
the surface shows no craters. Callisto, on
the other hand, is not geologically active
and thus is not resurfaced regularly, which
explains why its surface is heavily cratered.
e correct answer is E.
429. Which of the following best describes the purpose of
the second paragraph of the passage?
(A) To provide further evidence of the systematic
variation in the characteristics of Jupiter’s four
largest moons
(B) To present a comprehensive theory to explain
the systematic variation in the characteristics of
Jupiter’s four largest moons
(C) To explain the signi cance of the systematic
variation in the characteristics of Jupiter’s four
largest moons
(D) To introduce facts that contradict conventional
assumptions about Jupiter’s four largest moons
(E) To contrast the characteristics of Jupiter’s four
largest moons with the characteristics of the
planets of the solar system
Evaluation
is question depends on understanding how the
second paragraph functions in the context of the
passage as a whole. e rst paragraph discusses
the way in which the composition of Jupiter’s four
largest moons varies with distance from Jupiter,
and the second paragraph extends the idea of
distance‐based variation to geological activity and
surface appearance.
A Correct. e second paragraph presents
evidence related to the amount of geological
activity and surface cratering in order to
extend the rst paragraph’s suggestion that
the characteristics of Jupiter’s four largest
moons vary systematically based on their
distance from Jupiter.
B e passage does not o er a theory to
account for the systematic variation in the
characteristics of Jupiter’s largest moons; it
merely describes several instances of that
variation.
7.6 Reading Comprehension Answer Explanations
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C e second paragraph provides more
examples of the systematic variation in the
characteristics of Jupiter’s largest moons
rather than explaining that variation’s
signi cance.
D e passage describes Jupiter’s moons
butdoes not identify any conventional
assumptions about those moons that are
contradicted by facts introduced in the
passage.
E e rst paragraph suggests that Jupiter’s
moons exhibit di erences in characteristics
that are more “systematic” than are those
ofthe planets in the solar system, but
the characteristics are not themselves
contrasted; in fact, the rst paragraph
suggests that they are similar. e second
paragraph does not discuss the planets of
the solar system at all.
e correct answer is A.
430. The author’s reference to Jupiter’s gravity in line 25
serves primarily to
(A) indicate why the absence of craters on Io’s
surface is surprising
(B) explain the presence of craters on the surface of
Jupiter’s four largest moons
(C) provide an explanation for the lack of geological
activity on Callisto
(D) contrast Jupiter’s characteristics with the
characteristics of its four largest moons
(E) illustrate the similarity between Jupiter’s four
largest moons and the planets of the solar
system
Evaluation
e reference to Jupiter’s gravity is part of the
author’s discussion of cratering on Jupiter’s
moons; Jupiter’s gravity is strong enough to
attract comets and asteroids that then bombard
its inner moons. A high bombardment rate
would seem to indicate that a great deal of
cratering would occur on those inner moons,
and yet the passage reports that, unexpectedly,
on the innermost moon, Io, no craters have been
detected.
A Correct. Jupiter’s gravity attracts comets
and asteroids, which increases the
bombardment rate of its inner moons,
including Io. is bombardment makes
it surprising that Io’s surface shows no
cratering.
B e passage discusses the likely e ect of
Jupiter’s gravity on its inner moons but not
its outer moons; two of the large moons the
passage discusses are outer moons.
C According to the passage, Callisto, an outer
moon, lacks geological activity because of
its distance from Jupiter; Jupiter’s gravity is
not o ered as a contributing factor to this
inactivity.
D e passage does not contrast Jupiter with
its moons; rather, it compares the moons to
one another.
E e rst paragraph of the passage suggests
that Jupiter’s moons vary in a way similar
tothat of the planets of the solar system,
butthe author does not refer to Jupiter’s
gravity to illustrate the similarity in this
variation.
e correct answer is A.
Questions 431–434 refer to the passage on page 376.
431. According to the passage, the research mentioned
in line 6 suggests which of the following about lower‐
ranked top executives and postacquisition success?
(A) Given that these executives are unlikely to
contribute to postacquisition success, little effort
should be spent trying to retain them.
(B) The shorter their length of service, the less likely
it is that these executives will play a signi cant
role in postacquisition success.
(C) These executives are less important to
postacquisition success than are more highly
ranked top executives.
(D) If they have long tenures, these executives may
prove to be as important to postacquisition
success as are more highly ranked top
executives.
(E) Postacquisition success is unlikely if these
executives are retained.
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Supporting idea
e question asks about information provided
by the passage. According to the third sentence,
research suggests that retaining the highest‐
level top executives in an acquisition is more
strongly associated with success than retaining
lower‐ranked top executives—which suggests,
in turn, that lower‐ranked top executives are
less important than top‐level executives to
postacquisition success, though it does not
suggest that they are unimportant to such success.
A e research indicates that lower‐ranked top
executives are less strongly associated with
success than are higher‐ranked executives
but does not provide advice about retention
e orts.
B e research mentioned in the third
sentence does not consider length of service.
C Correct. e research indicates that lower‐
ranked top executives are less strongly
associated with postacquisition success than
are the highest‐ranked executives.
D e research mentioned in the third
sentence does not consider length of service.
E e research suggests that lower‐ranked top
executives are less strongly associated with
postacquisition success but does not suggest
that they decrease the likelihood of success.
e correct answer is C.
432. The resource‐based view, as described in the passage,
is based on which of the following ideas?
(A) The managerial skills of top executives become
strongest after the rst ve years of their tenure.
(B) Company‐speci c knowledge is an important
factor in the success of an acquisition process.
(C) The amount of nontransferable knowledge
possessed by long‐tenured top executives tends
to be underestimated.
(D) Effective implementation of an acquisition
depends primarily on the ability of executives to
adapt to change.
(E) Short‐tenured executives are likely to impede
the implementation of a successful acquisition
strategy.
Evaluation
is question requires analysis of the reasoning
underlying one of the two explanations described
in the passage. e resource‐based view (RBV)
holds that retaining high‐level executives with
long tenure will contribute to success because
those people have important company‐speci c
knowledge. is view rests on the assumption
that company‐speci c knowledge is valuable to
postacquisition success.
A In RBV, executives with long tenure are
valuable not speci cally for their managerial
skills but for their knowledge about the
acquired company. e passage does not
restrict to ve years the period in which this
knowledge is gained.
B Correct. RBV values executives’ knowledge
of the acquired company and is based on the
belief that company‐speci c knowledge is
valuable for postacquisition success.
C e passage does not indicate that RBV
claims that executives’ company‐speci c
knowledge is generally undervalued. But the
passage does indicate that RBV regards such
knowledge as valuable to postacquisition
success.
D In RBV, executives with long tenure are
valuable not for their ability to adapt to
change, but for their knowledge about the
acquired company.
E RBV does not suggest that short‐tenured
executives impede postacquisition success,
only that they are less important to success
than the highest‐ranked executives.
e correct answer is B.
433. The passage suggests that Bergh and a proponent of
the upper echelons perspective would be most likely to
disagree over which of the following?
(A) Whether there is a positive correlation between
short organizational tenure and managerial
adaptability
(B) Whether there is a positive correlation between
long organizational tenure and the acquisition of
idiosyncratic and nontransferable knowledge
(C) Whether adaptability is a useful trait for an
executive who is managing an acquisition
process
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
440
(D) Whether retaining less‐tenured top executives of
an acquired company is an optimal strategy for
achieving postacquisition success
(E) Whether retaining highest‐level top executives
of acquired companies is more important than
retaining lower‐ranked top executives
Inference
e question asks about conclusions that can
reasonably be drawn from the information
provided in the passage. Bergh’s study supports
the resource‐based view (RBV), which suggests
that top executives with long tenure are more
valuable to postacquisition success than other
executives. e upper echelons perspective
(UEP), in contrast, suggests that top executives
with shorter tenure are more valuable to
postacquisition success. us, Bergh and a
proponent of UEP would likely disagree about
whether long or short tenure top executives
are more valuable to a positive outcome in a
postacquisition situation.
A e passage does not provide su ciently
speci c information about statistical
relationships to determine whether Bergh
and proponents of UEP would agree or
disagree about whether there is such a
positive correlation.
B ere is a weak suggestion in the passage
that Bergh believes such a positive
correlation exists, but there is no indication
that a proponent of UEP would question
such a correlation.
C e passage does not indicate that Bergh
would disagree with proponents of UEP
that adaptability is a valuable trait in an
executive who is managing an acquisition.
D Correct. e passage suggests that
proponents of UEP believe that retaining
less‐tenured top executives during and after
an acquisition is a better strategy, while
Bergh believes that retaining longer‐tenured
top executives is better.
E e passage suggests that Bergh and
proponents of UEP agree that retaining
the highest‐level top executives is more
important to postacquisition success than is
retaining lower‐ranked top executives.
e correct answer is D.
434. According to the passage, prior to Bergh’s study,
research on the role of top executives of acquired
companies in business acquisition success was limited
in which of the following ways?
(A) It did not address how the organizational
tenure of top executives affects postacquisition
success.
(B) It did not address why some companies have
longer‐tenured CEOs than others.
(C) It did not consider strategies for retaining long‐
tenured top executives of acquired companies.
(D) It failed to differentiate between the
contribution of highest‐level top executives
to postacquisition success and that of
lower‐ranked top executives.
(E) It underestimated the potential contribution
that lower‐level top executives can make to
postacquisition success.
Supporting idea
is question asks about information explicitly
provided in the passage. e rst paragraph
summarizes research indicating that retaining
highest‐level top executives during and after
an acquisition is more strongly associated
with successful outcomes than retaining
lower‐ranking top executives. e paragraph
then states that this research has limitations,
including failing to take into account how long
the highest‐ranking executives have worked for
the company. e second paragraph explains that
Bergh’s study responds to those limitations by
analyzing the role of tenure (length of service in
the organization).
A Correct. e passage indicates that the
research about the role of highest‐level
executives in acquisitions is limited by its
failure to consider tenure.
B e passage does not portray the failure of
the research to address this as a limitation of
the research in question.
C e passage does not portray the failure of
the research to consider this as a limitation
of the research in question.
D e passage indicates that the research does,
in fact, di erentiate between the respective
contributions of these two groups of top
executives.
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441
E Undervaluing the contributions of lower‐
level top executives is not one of the
limitations mentioned in the passage.
e correct answer is A.
Questions 435–438 refer to the passage on page 378.
435. According to the passage, which of the following
contributed to Marcus Garvey’s success?
(A) He introduced cultural and historical
consciousness to the African American
community.
(B) He believed enthusiastically in the traditional
American success ethos.
(C) His audience had already formed a
consciousness that made it receptive to his
message.
(D) His message appealed to critics of African
American support for United States military
involvement in the First World War.
(E) He supported the movement to protest
segregation that had emerged prior to his arrival
in the United States.
Supporting idea
To answer this question, nd what the passage
states explicitly about how Marcus Garvey
achieved his success. e passage begins by
stating that Garvey arrived at the right time: that
returning African American soldiers were primed
to receive what he had to say about the African
American community. ese soldiers already held
strong beliefs about their rights to opportunities
for success; the passage concludes that the divide
between the soldiers’ expectations and their
experiences led to Garvey’s success.
A e passage states that African American
people were in possession of a strong
cultural and historical consciousness prior to
Garvey’s arrival in the United States.
B e passage attributes belief in the
traditional American success ethos to
African American people who joined the
armed forces; it does not mention Garvey’s
beliefs on this subject.
C Correct. African American soldiers who
had experienced segregation during the
First World War were ready to hear what
Garvey had to say.
D Critics of African American support for
United States involvement in the First
World War are not mentioned in the
passage.
E While Garvey most likely would have
supported a movement to protest
segregation, such a movement is not
discussed in the passage.
e correct answer is C.
436. The passage suggests that many African American
people responded to their experiences in the armed
forces in which of the following ways?
(A) They maintained as civilians their enthusiastic
allegiance to the armed forces.
(B) They questioned United States involvement in the
First World War.
(C) They joined political organizations to protest the
segregation of African American troops and the
indignities they suffered in the military.
(D) They became aware of the gap between their
expectations and the realities of American
culture.
(E) They repudiated Garvey’s message of pride and
unity.
Inference
According to the passage, African Americans
enthusiastically joined the armed services but
were confronted with continued segregation, both
in the military and when they returned home. e
passage does not explicitly state their response to
these experiences, but a response can be inferred.
e second paragraph refers to anthropologist
Anthony F. C. Wallace, who argued that a
revitalization movement may be brought about
by the perception of a gap between expectations
and reality, and such a revitalization did occur in
African American communities following the
First World War; thus, many African American
people may have become aware of a gap such as
Wallace described.
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
442
A e passage states that African American
troops experienced segregation and other
indignities while in the military; these
experiences could reasonably be inferred to
have dampened their enthusiasm for the
armed forces. Regardless, the passage does
not suggest an enthusiastic allegiance.
B e passage describes African American
people’s enthusiasm about joining the
military. Although they experienced
segregation and other indignities while in
the military, the passage does not suggest
that their opinion about involvement in the
war changed.
C While African American troops may have
joined political organizations, the passage
does not provide any actual evidence of this
having occurred.
D Correct. e fact that, as the passage states,
a revitalization movement occurred in the
African American community following the
First World War suggests that the returning
soldiers did become aware of the gap
between their expectations of an improved
situation with regard to segregation and
the reality of continued segregation in the
United States.
E e passage does not suggest that African
American troops repudiated Garvey’s
message. On the contrary, it states that
Garvey built the largest revitalization
movement in African American history . is
suggests that the members of the African
American community, including the
returning soldiers, were extremely receptive
to Garvey’s message.
e correct answer is D.
437. It can be inferred from the passage that the “scholars”
mentioned in line 24 believe which of the following to
be true?
(A) Revitalization resulted from the political activism
of returning African American soldiers following
the First World War.
(B) Marcus Garvey had to change a number of
prevailing attitudes in order for his mass
movement to nd a foothold in the United States.
(C) The prevailing sensibility of the African American
community provided the foundation of Marcus
Garvey’s political appeal.
(D) Marcus Garvey hoped to revitalize consciousness
of cultural and historical identity in the African
American community.
(E) The goal of the mass movement that Marcus
Garvey helped bring into being was to build on
the pride and unity among African Americans.
Inference
To determine what it is logical to infer regarding
the scholars discussed in the third paragraph,
look at the context in which they are mentioned.
According to the passage, these scholars argue
that Garvey was responsible for creating a
particular consciousness within the African
American community, a consciousness that the
passage identi es as identity, strength, and [a]
sense of history. Unlike the passage author, these
scholars believe strongly in Garvey’s responsibility
for this consciousness, so they would most likely
reject any suggestion that it existed prior to his
arrival and activism.
A According to the passage, the scholars
believe that Garvey was responsible for
the creation of the consciousness that
led to revitalization, which suggests that
revitalization resulted from Garvey’s
activism, not soldiers’ activism.
B Correct. According to the passage, the
scholars believe that Garvey created the
consciousness that led to his revitalization
movement. is suggests that he had to
change prevailing attitudes in order to foster
this new consciousness.
C According to the passage, the scholars believe
that Garvey created a new consciousness in
the African American community; thus, the
prevailing sensibility could not have provided
a foundation for his appeal.
D According to the passage, the scholars
believe that Garvey built his revitalization
movement on a new consciousness of
cultural and historical identity, not a
previously existing one.
E According to the passage, the scholars’
position is that Garvey’s movement was
built on a new sense of pride and unity that
he provided, and that that sense did not
precede Garvey’s work.
e correct answer is B.
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443
438. According to the passage, many African American
people joined the armed forces during the First World
War for which of the following reasons?
(A) They wished to escape worsening economic
conditions in African American communities.
(B) They expected to ful ll ideals of personal
attainment.
(C) They sought to express their loyalty to the United
States.
(D) They hoped that joining the military would help
advance the cause of desegregation.
(E) They saw military service as an opportunity to
ful ll Marcus Garvey’s political vision.
Supporting idea
is question depends on identifying what the
passage states directly about African American
people’s reasons for joining the armed forces. e
reason o ered by the passage is that the African
American people who entered the armed forces
did so because they were hoping to participate in
the traditional American ethos of individual success .
A Although this is a plausible reason for
entering the armed forces, the passage does
not discuss economic conditions.
B Correct. e passage states that African
American people who joined the armed
forces during the First World War wanted
to achieve individual success.
C e passage does not discuss African
American people’s loyalty to the United
States.
D e passage states that African American
troops experienced segregation, but it
does not suggest that they had hoped
their joining the military would promote
desegregation.
E e passage suggests that African American
troops did not become aware of Marcus
Garvey’s political vision until after they
returned from the First World War.
e correct answer is B.
Questions 439–441 refer to the passage on page 380.
439. The primary purpose of the passage is to
(A) compare the adaptive responses of several
species of columnar cacti in the Sonoran Desert
with those in the arid tropical regions of southern
Mexico
(B) discuss some of the possible causes of the
relatively low abundance of migratory nectar-
feeding bats in the Sonoran Deser t
(C) provide a possible explanation for a particular
evolutionary change in certain species of
columnar cacti in the Sonoran Desert
(D) present recent ndings that challenge a
particular theory as to why several species
of columnar cacti in the Sonoran Desert have
expanded their range of pollinators
(E) compare the effectiveness of nocturnal and
diurnal pollination for several different species of
columnar cacti in the Sonoran Desert
Main idea
is question depends on understanding the
passage as a whole. e rst paragraph discusses
an evolutionary change undergone by columnar
cacti in the Sonoran Desert with regard to
pollination. e second paragraph o ers a
possible reason for this change—migratory
nectar-feeding bats are unreliable pollinators—
and the third paragraph goes on to provide
evidence that supports the reason given in the
second paragraph.
A e passage does compare the adaptations
of cacti in the Sonoran Desert with those of
cacti in southern Mexico, but it does so in
support of a larger point about the Sonoran
Desert cacti.
B e relatively low abundance of migratory
nectar-feeding bats in the Sonoran Desert is
important to the passage in that it provides
a reason why the columnar cacti in that
region have made certain adaptations. But
the passage does not explain why the bats
are not particularly abundant.
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
444
C Correct. e owers of the columnar cacti
in the Sonoran Desert have evolved to
remain open after sunrise, and the passage
is primarily concerned with explaining why
this change may have taken place.
D e passage presents recent ndings that
support, rather than challenge, a theory as
to why the columnar cacti of the Sonoran
Desert have expanded their range of
pollinators. e passage does not allude
to any competing theory that may be
challenged by the ndings.
E Any comparison of the e ectiveness of
nocturnal and diurnal pollination for
columnar cacti in the Sonoran Desert is
made in support of the passage’s primary
concern: explaining why these cacti have
come to remain open and receptive to
pollination in daylight.
e correct answer is C.
440. According to the passage, which of the following types
of nectar-feeding pollinators is likely to be an unreliable
pollinator of a particular cactus ower?
(A) A dietary specialist whose abundance is typically
high in relation to that of the ower
(B) A dietary specialist whose abundance is at times
signi cantly lower than that of the ower
(C) A dietary generalist for whom that ower’s
nectar is not a preferred food but is the most
consistently available food
(D) A dietary generalist for whom that ower’s nectar
is slightly preferred to other available foods
(E) A dietary generalist that evolved from a species
of dietary specialists
Supporting idea
is question depends on recognizing the
qualities of an unreliable pollinator, as described
in the passage. e second paragraph addresses
this issue: it explains that the unreliability of
pollinators can arise in any of three ways: they
may be dietary generalists with alternative sources
of food; they may be dietary specialists whose
own abundance varies; or they may be dietary
specialists whose abundance is chronically low in
relation to the owers.
A A dietary specialist whose abundance is
high in relation to the owers on which it
feeds would likely be a reliable pollinator.
B Correct. A dietary specialist whose
abundance is at times signi cantly lower
than that of the ower it pollinates would
be, according to the passage, unreliable.
C A dietary generalist who nds the ower
of a particular species more consistently
available than other suitable food sources
would most likely be a reliable pollinator of
that ower.
D A dietary generalist who prefers the ower’s
nectar would likely be a reliable pollinator of
that ower compared to other owers.
E e passage provides no reason to believe
that the evolution of a pollinator’s dietary
preference has any bearing on its reliability
as a pollinator.
e correct answer is B.
441. According to the passage, present-day columnar cacti
in the Sonoran Desert differ from their close relatives
in southern Mexico in that the Sonoran cacti
(A) have owers that remain open after sunset
(B) are pollinated primarily by dietary specialists
(C) can be pollinated by nectar-feeding bats
(D) have stigmas that are unreceptive to pollination
at night
(E) are sometimes pollinated by diurnal pollinators
Supporting idea
is question depends on identifying a di erence
noted in the passage between columnar cacti
in the Sonoran Desert and their relatives in
southern Mexico. e rst paragraph states that
in southern Mexico, columnar cactus owers are
not receptive to pollination by diurnal pollinators,
whereas in the Sonoran Desert, the owers have
evolved to allow diurnal pollination.
A e cacti in both the Sonoran Desert and
southern Mexico have owers that remain
open after sunset, because cacti in both
locations can be pollinated nocturnally.
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445
B Sonoran Desert cacti are pollinated, at least
partially, by nectar-feeding bats, which are
dietary specialists. But the cacti in southern
Mexico are pollinated by these specialists,
too.
C Sonoran Desert cacti can be pollinated by
nectar-feeding bats—but so can cacti in
southern Mexico.
D Cacti in the Sonoran Desert have stigmas
that have evolved to be receptive to
pollination both at night and during the day .
E Correct. e distinction between cacti in
the Sonoran Desert and those in southern
Mexico is that Sonoran Desert cacti
have evolved to allow pollination during
the day—that is, pollination by diurnal
pollinators.
e correct answer is E.
Questions 442–449 refer to the passage on page 382.
442. The passage provides information in support of which
of the following assertions?
(A) The disadvantages of an adaptation to a
particular feature of an environment often
outweigh the advantages of such an adaptation.
(B) An organism’s reaction to being placed in an
environment to which it is not well adapted can
sometimes illustrate the problems that have
been solved by the adaptations of organisms
indigenous to that environment.
(C) The effectiveness of an organism’s adaptation to
a particular feature of its environment can only
be evaluated by examining the effectiveness with
which organisms of other species have adapted
to a similar feature of a different environment.
(D) Organisms of the same species that inhabit
strikingly different environments will often adapt
in remarkably similar ways to the few features of
those environments that are common.
(E) Different species of organisms living in the same
environment will seldom adapt to features of that
environment in the same way.
Application
is question requires recognizing a principle
underlying the passage’s overall discussion. e
passage makes a general claim about terrestrial
animals’ need to overcome the e ect of gravity
on their blood circulation systems, and it then
uses the speci c example of terrestrial snakes
to illustrate this claim. To help identify the
adaptations used by terrestrial snakes, the
passage describes what happens to sea snakes,
which are aquatic and less a ected by gravity’s
in uence, when they are subjected to a terrestrial
environment. e speci c problems faced by these
snakes strongly suggest that terrestrial snakes
have developed ways to overcome these problems.
e passage then identi es speci c physiological
di erences between sea snakes and terrestrial
snakes that demonstrate how terrestrial snakes
overcome gravity’s in uence.
A e passage discusses how species have
successfully adapted to their speci c
environments and does not mention that
these adaptations create disadvantages in
that environment.
B Correct. e passage discusses the problems
faced by sea snakes when they are subjected
to a terrestrial environment and then
examines terrestrial snakes to illustrate how
certain adaptations solved these problems.
C e passage is not concerned with
evaluating the e ectiveness of species’
adaptations to their environments; it takes
for granted that these adaptations are
e ective.
D e passage is concerned with how species
adapt di erently to di erent environments
and not with how adaptations to di erent
environments are similar.
E e passage discusses how di erent
environments a ect how species have
adapted, not how di erent species adapt to a
similar environment.
e correct answer is B.
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
446
443. According to the passage, one reason that the
distribution of blood in the sea snake changes little
while the creature remains in the ocean is that
(A) the heart of the sea snake tends to be located
near the center of its body
(B) pressure gradients in the water surrounding
the sea snake counter the effects of vertical
pressure gradients within its blood vessels
(C) the sea snake assumes a vertical posture less
frequently than do the terrestrial and the arboreal
snake
(D) the sea snake often relies on waves of muscle
contractions to help move blood from the torso
to the head
(E) the force of pressure gradients in the water
surrounding the sea snake exceeds that of
vertical pressure gradients within its circulatory
system
Supporting ideas
is question asks for an identi cation of
factual information in the passage. Given that
the contrast between sea snakes and terrestrial
snakes is being used to identify adaptations
used by terrestrial animals to overcome the
e ect of gravity on their circulation systems, the
passage needs initially to illustrate why it is that
sea snakes are not confronted with the same
problems that gravity causes for terrestrial snakes.
is information therefore needs to come fairly
early in the passage.
A e passage identi es the location of a sea
snake’s heart as a factor that minimizes
the e ort required to pump blood to both
extremities but not as a cause of the even
distribution of blood in sea snakes.
B Correct. e passage states explicitly in
lines 11–17 that while sea snakes are in
the ocean, the vertical pressure gradients in
their blood vessels are counteracted by the
pressure gradients in the water.
C e passage does not discuss the frequency
with which any snakes assume certain
postures.
D e passage discusses muscle contractions
only in relation to arboreal snakes.
E e passage states that the vertical
pressures within sea snakes’ blood vessels
are counteracted (line 13) by the water’s
pressure, which suggests that the pressures
are equalized, not that one force exceeds the
other.
e correct answer is B.
444. It can be inferred from the passage that which of the
following is true of species of terrestrial snakes that
often need to assume a vertical posture?
(A) They are more likely to be susceptible to
circulatory failure in vertical postures than are
sea snakes.
(B) Their hearts are less likely to be located at the
midpoint of their bodies than is the case with sea
snakes.
(C) They cannot counteract the pooling of blood in
lower regions of their bodies as effectively as
sea snakes can.
(D) The blood pressure at their midpoint decreases
signi cantly when they are tilted with their
headsup.
(E) They are unable to rely on muscle contractions
to move venous blood from the lower torso to
the head.
Inference
is question requires using information given
about how arboreal snakes, which are frequently
in vertical postures, have adapted to gravity’s
in uence to make an assumption that other
terrestrial snakes that are frequently in these
postures are likely to have similar adaptations.
e passage implies that sea snakes have hearts at
the midpoint of their bodies because the water’s
pressure gradients help distribute blood evenly. It
then illustrates that arboreal snakes have hearts
closer to their heads to help keep blood owing
to their brains when they are in vertical postures.
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447
A e passage does not suggest that any of the
snakes mentioned are ill‐adapted to their
particular environments.
B Correct. e passage states that arboreal
snakes have hearts close to their heads and
not at the midpoints of their bodies, so it is
reasonable to conclude that any terrestrial
snake that frequently assumes vertical
postures would be unlikely to have hearts at
their bodies’ midpoint.
C As with answer choice (A), the passage does
not suggest that any species of snake is ill‐
adapted to its environment.
D e passage states that sea snakes lose
pressure at their midpoints when they
are tilted on land with heads up but that
terrestrial snakes do not have this problem.
E Because arboreal snakes use muscle
contractions to circulate blood when they
are vertical, it is likely that most terrestrial
snakes that frequently assume vertical
postures also have this capability.
e correct answer is B.
445. The author describes the behavior of the circulatory
system of sea snakes when they are removed from the
ocean (see lines 17–20) primarily in order to
(A) illustrate what would occur in the circulatory
system of terrestrial snakes without adaptations
that enable them to regulate their blood pressure
in vertical orientations
(B) explain why arboreal snakes in vertical
orientations must rely on muscle contractions to
restore blood pressure to the brain
(C) illustrate the effects of circulatory failure on the
behavior of arboreal snakes
(D) illustrate the superiority of the circulatory system
of the terrestrial snake to that of the sea snake
(E) explain how changes in spatial orientation can
adversely affect the circulatory system of snakes
with hearts located in relatively close proximity
to their heads
Evaluation
Answering this question requires understanding
why sea snakes have been brought into the
passage’s overall discussion about how terrestrial
animals have overcome the in uence of gravity
on their blood circulation. e passage uses the
e ects that gravity has on sea snakes when they
are taken out of water to identify problems that
terrestrial snakes must have adapted to in order to
survive.
A Correct. e passage uses the problems
sea snakes have when taken out of water to
illustrate that without certain adaptations,
terrestrial snakes would likely have similar
problems.
B e passage discusses sea snakes to illustrate
problems faced by terrestrial snakes, not to
explain how terrestrial snakes have adapted
to gravity’s in uence.
C e passage does not discuss the e ects of
circulatory failure on arboreal snakes.
D e passage does not compare or contrast
the e ectiveness of the various adaptations
used by di erent snakes.
E e passage does not imply that snakes with
hearts close to their heads are adversely
a ected by spatial positions.
e correct answer is A.
446. It can be inferred from the passage that which of the
following is a true statement about sea snakes?
(A) They frequently rely on waves of muscle
contractions from the lower torso to the head to
supplement the work of the heart.
(B) They cannot effectively regulate their blood
pressure when placed in seawater and tilted at
an angle with the head pointed downward.
(C) They are more likely to have a heart located in
close proximity to their heads than are arboreal
snakes.
(D) They become acutely vulnerable to the effects
of gravitational pressure on their circulatory
system when they are placed in a terrestrial
environment.
(E) Their cardiovascular system is not as
complicated as that of arboreal snakes.
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
448
Inference
Answering this question requires understanding
why sea snakes are discussed in the passage and
what happens to them when they are taken out
of water and subjected to the force of gravity. e
second paragraph implies strongly that sea snakes
will not survive certain terrestrial situations for
which they are not adapted.
A e passage associates muscle contractions
to circulate blood with arboreal snakes only.
B According to the passage, sea snakes’
inability to regulate blood pressure occurs
only when they are taken out of water.
C e passage states clearly that arboreal
snakes have hearts closer to their heads than
do sea snakes.
D Correct. e passage states that in certain
postures, sea snakes placed in a terrestrial
environment will lose all blood pressure at
their brains, which is an acute vulnerability.
E e passage does not provide the
information needed to compare the
complexity of the various snakes discussed.
e correct answer is D.
447. The author suggests that which of the following is a
disadvantage that results from the location of a snake’s
heart in close proximity to its head?
(A) A decrease in the ef ciency with which the snake
regulates the ow of blood to the brain
(B) A decrease in the number of orientations in
space that a snake can assume without loss of
blood ow to the brain
(C) A decrease in blood pressure at the snake’s
midpoint when it is tilted at various angles with
its head up
(D) An increase in the tendency of blood to pool
at the snake’s head when the snake is tilted at
various angles with its head down
(E) An increase in the amount of effort required to
distribute blood to and from the snake’s tail
Inference
is question asks for an inference about the
location of a snake’s heart being closer to the
brain than to the midpoint of its body. In the
third paragraph, the passage states that in
terrestrial snakes, which must ght the in uence
of gravity, the closer proximity of the heart to
the head ensures blood circulation to the brain.
e passage notes, however, that this makes it
more di cult for such snakes to maintain blood
circulation to the tail.
A e passage states that snakes have hearts
closer to their heads to more e ciently
circulate blood to the brain.
B e passage suggests that having the heart
close to the head increases the spatial
orientations a snake can assume without
losing blood ow to the brain, rather than
decreases the number of orientations.
C e passage indicates that this is true only
of sea snakes with hearts near their body’s
midpoint.
D e passage mentions blood pooling in the
lower portions of a terrestrial organism’s
body but does not imply that blood can pool
at a snake’s head.
E Correct. Because, as the passage states, it is
more di cult for a snake with its heart close
to its head to circulate blood to the tail, and
therefore its body is likely to put more e ort
into circulating blood to the tail.
e correct answer is E.
448. The primary purpose of the third paragraph is to
(A) introduce a topic that is not discussed earlier in
the passage
(B) describe a more ef cient method of achieving an
effect discussed in the previous paragraph
(C) draw a conclusion based on information
elaborated in the previous paragraph
(D) discuss two speci c examples of phenomena
mentioned at the end of the previous paragraph
(E) introduce evidence that undermines a view
reported earlier in the passage
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449
Evaluation
Answering this question requires recognizing
how the passage develops its main point. e
rst paragraph sets up a general claim about
gravity’s in uence on terrestrial organisms. e
second paragraph then describes the ill e ects that
gravity has on sea snakes to identify problems that
terrestrial snakes have had to adapt to. e third
paragraph then uses examples to illustrate how
terrestrial snakes have adapted to gravity’s in uence.
A e topic of the third paragraph is the
adaptations developed by terrestrial snakes
to survive gravity’s in uence, which is part
of the discussion in both the rst and second
paragraphs.
B ere is no comparison in the passage of the
e ciency of the di erent methods used by
snakes to adapt to gravity’s in uence.
C e third paragraph is concerned with
illustrating certain adaptations used by snakes
and o ers no conclusions about the problems
terrestrial snakes have had to adapt to, which
is the topic of the second paragraph.
D Correct. e end of the second paragraph
refers to certain adaptations (line 23) that the
third paragraph then goes on to identify and
discuss.
E e third paragraph supports the main idea
of the passage and is not used to counter
any claim made earlier.
e correct answer is D.
449. In the passage, the author is primarily concerned with
doing which of the following?
(A) Explaining adaptations that enable the terrestrial
snake to cope with the effects of gravitational
pressure on its circulatory system
(B) Comparing the circulatory system of the sea
snake with that of the terrestrial snake
(C) Explaining why the circulatory system of the
terrestrial snake is different from that of the sea
snake
(D) Pointing out features of the terrestrial snake’s
cardiovascular system that make it superior to
that of the sea snake
(E) Explaining how the sea snake is able to
neutralize the effects of gravitational pressure on
its circulatory system
Main idea
Answering this question involves assessing
what the passage as a whole is attempting to
do. While the passage begins by making a
general claim about gravity’s in uence on the
cardiovascular systems of terrestrial animals, it
immediately points to terrestrial snakes as a good
example supporting this claim. e rest of the
passage is then devoted to illustrating, using the
observations involving sea snakes, how gravity’s
in uence has shaped the cardiovascular systems
of terrestrial snakes.
A Correct. e entire passage is devoted to an
explanation of how terrestrial snakes have
adapted to gravity’s in uence.
B While the passage does compare the
systems of the two snakes, it does so for the
larger purpose of demonstrating gravity’s
in uence on terrestrial snakes.
C e passage is more concerned with how
the systems of the two snakes are di erent,
rather than why , in order to identify how
terrestrial snakes have adapted to gravity’s
in uence.
D ere is no judgment in the passage as to
the superiority of one snake’s system over
the other.
E While the passage does explain how sea
snakes do this, it does so only for the larger
purpose of identifying how terrestrial snakes
have adapted to gravity’s in uence.
e correct answer is A.
Questions 450–455 refer to the passage on page 386.
450. The passage is primarily concerned with
(A) contrasting the bene ts of one methodology with
the bene ts of another
(B) describing the historical origins and inherent
drawbacks of a particular methodology
(C) discussing the appeal of a particular
methodology and some concerns about its use
(D) showing that some historians’ adoption of a
particular methodology has led to criticism of
recent historical scholarship
(E) analyzing the in uence of current feminist views
on women’s interpretations of their experience
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
450
Main idea
is question asks for an abstract view of what
the passage as a whole is primarily doing. e
passage introduces a particular methodology
that scholars of women’s history have been
encouraged to employ, explaining why the use of
the methodology is supported. e passage then
goes on to raise some concerns about the use of
the methodology and cites one example in which
caution is needed.
A e passage is primarily concerned with
only one methodology.
B e passage mentions why the methodology
had been encouraged but does not give
the history of its origins; while it cautions
historians to employ the methodology
carefully, it is not concerned with drawbacks
of its proper use.
C Correct. e passage discusses why the use
of a methodology is being encouraged and
then o ers some concerns about its use.
D e passage does not discuss any criticism
of recent scholarship in women’s history.
E ere is no mention in the passage that
feminist theory is in uencing how women
in general think about their experiences.
e correct answer is C.
451. According to the passage, which of the following
shapes the oral narratives of women storytellers?
(A) The conventions for standard histories in the
culture in which a woman storyteller lives
(B) The conventions of storytelling in the culture in
which a woman storyteller lives
(C) A woman storyteller’s experience with distinctive
traditions of storytelling developed by the women
in her family of origin
(D) The cultural expectations and experiences of
those who listen to oral narratives
(E) A woman storyteller’s familiarity with the stories
that members of other groups in her culture tell
to explain themselves
Supporting ideas
is question asks for an identi cation of speci c
information provided by the passage. In the
second paragraph, the passage describes certain
concerns about using oral narratives. One of these
concerns is that the stories people tell to explain
themselves are shaped by . . . storytelling conventions
(lines 17–19) and other in uences tied to the
teller’s cultural and historical context.
A e passage uses standard histories (line 7) to
refer to the usual work of scholars and not
to something that in uences oral narratives.
B Correct. e passage raises as a concern
that oral narratives may be in uenced by
storytelling conventions present in the
culture of the speaker.
C e passage does not mention the family of
origin of women storytellers.
D e passage does not mention the
expectations of the listeners of oral
narratives.
E e passage does not discuss women
storytellers’ familiarity with the oral
narratives belonging to other groups of
women.
e correct answer is B.
452. The author of the passage would be most likely to
make which of the following recommendations to
scholars of women’s history?
(A) They should take into account their own life
experiences when interpreting the oral accounts
of women’s historical experiences.
(B) They should assume that the observations made
in women’s oral narratives are believed by the
intended audience of the story.
(C) They should treat skeptically observations
reported in oral narratives unless the
observations can be con rmed in standard
histories.
(D) They should consider the cultural and historical
context in which an oral narrative was created
before arriving at an interpretation of such a
narrative.
(E) They should rely on information gathered from
oral narratives only when equivalent information
is not available in standard histories.
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451
Application
Answering this question involves recognizing
what the author believes about oral narratives
andthen applying this belief to a hypothetical
situation in which the author makes
recommendations to scholars of women’s
history. While acknowledging the appeal of
oral narratives to these scholars, in the second
paragraph the author urges caution when
using these narratives as sources of disinterested
commentary (line 16). e passage then states
that people’s oral narratives are shaped by cultural
and historical factors (line 20), which presumably
relate to the cultural and historical context within
which the narratives are spoken.
A e passage does not mention the personal
life experiences of scholars.
B e passage does not mention the intended
audiences of oral narratives.
C e passage mentions standard histories
(line7) only as a reference to scholarly
works that often have shortcomings.
D Correct. e passage cautions that oral
narratives may be biased due to cultural
and historical factors, and it is therefore
reasonable to suppose that the author would
recommend that scholars consider this when
using such information.
E e passage does not refer to oral narratives
as being valuable only for lling a gap in the
available historical record.
e correct answer is D.
453. Which of the following best describes the function of
the last sentence of the passage?
(A) It describes an event that historians view as
crucial in recent women’s history.
(B) It provides an example of how political rhetoric
may in uence the interpretations of experience
reported in women’s oral narratives.
(C) It provides an example of an oral narrative that
inaccurately describes women’s experience
during a particular historical period.
(D) It illustrates the point that some women are more
aware than others of the social forces that shape
their oral narratives.
(E) It identi es the historical conditions that led to
the social acceptance of women’s paid work
outside the home.
Evaluation
is question requires recognizing how a
particular part of the passage is related to
the overall reasoning in the passage. e rst
paragraph introduces a methodology and
describes the methodology’s appeal. e second
paragraph then raises concerns about the use
of the methodology, drawing attention to the
cultural and historical bias that may be present
in oral narratives. In line 21, the passage refers
speci cally to the in uence political rhetoric
may have on a woman’s understanding of her
experience. In the nal sentence, the passage
provides a speci c hypothetical example of a
woman at the time of the Second World War to
illustrate this concern.
A e last sentence employs a hypothetical
example and does not describe a particular
event as being important to historians.
B Correct. After contending that political
rhetoric may in uence oral narratives, the
passage uses the example of the Second
World War in the nal sentence to support
this claim.
C e last sentence does not provide a
particular example of an oral narrative.
D e passage does not claim that some
women are more aware than others of the
social forces that may bear on them.
E e passage does not claim that social
conditions during the Second World
War led to acceptance of women in the
workplace.
e correct answer is B.
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
452
454. According to the passage, scholars of women’s history
should refrain from doing which of the following?
(A) Relying on traditional historical sources when
women’s oral narratives are unavailable
(B) Focusing on the in uence of political rhetoric on
women’s perceptions to the exclusion of other
equally important factors
(C) Attempting to discover the cultural and historical
factors that in uence the stories women tell
(D) Assuming that the conventions of women’s
written autobiographies are similar to the
conventions of women’s oral narratives
(E) Accepting women’s oral narratives less critically
than they accept women’s written histories
Inference
Answering this question requires recognizing
which option is directly inferable from
information in the passage. After describing
in the rst paragraph why oral narratives are
appealing to historians, the passage begins the
second paragraph by imploring scholars of
women’s history to be as cautious about accepting
oral narratives … as … written memories (lines
12–14). e passage then goes on to describe
potential bias in oral narratives, suggesting that
scholars should be as critical of them as they are
of written sources.
A e passage does not claim that traditional
historical sources should be avoided by
scholars.
B e passage mentions the in uence of
political rhetoric merely as one example of
potential bias.
C e passage suggests that scholars should
attempt to be aware of cultural and
historical factors.
D e passage does not discuss the
conventions of women’s written
autobiographies.
E Correct. e passage implies that written
histories and oral narratives should receive
the same level of critical scrutiny by
scholars.
e correct answer is E.
455. According to the passage, each of the following is a
difference between women’s oral narratives and most
standard histories EXCEPT:
(A) Women’s oral histories validate the signi cance
of women’s achievements.
(B) Women’s oral histories depict experience from
the point of view of women.
(C) Women’s oral histories acknowledge the
in uence of well‐known women.
(D) Women’s oral histories present today’s women
with a sense of their historical relationship to
women of the past.
(E) Women’s oral histories are crucial to the
collective identity of today’s women.
Supporting ideas
is question asks for information that is
stated inthe passage, and it requires a process
of elimination. In line 7, oral narratives are
presented as being unlike most standard histories ,
and the passage then goes on in lines 7–11 to list
characteristics of oral histories that most standard
histories do not have. e answer to this question
will therefore contain a characteristic of women’s
oral histories that is not described in lines 7–11.
A e passage states that, unlike most
standard histories, women’s oral histories
a rm the importance of women’s contributions
(lines 8–9).
B e passage states that, unlike most
standard histories, women’s oral histories
represent experience from the perspective of
women (lines 7–8).
C Correct. e passage does not mention the
in uence of well‐known women on women’s
oral histories.
D e passage states that, unlike most
standard histories, women’s oral histories
furnish present‐day women with historical
continuity (lines 9–10).
E e passage states that, unlike most
standard histories, women’s oral histories
furnish a historical sense that is essential to
their identity, individually and collectively
(line 11).
e correct answer is C.
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453
Questions 456–460 refer to the passage on page 388.
456. The passage suggests that in order for a manufacturer
in a capital‐intensive industry to have a decisive
advantage over competitors making similar products,
the manufacturer must
(A) be the rst in the industry to build production
facilities of theoretically optimal size
(B) make every effort to keep xed and sunk costs
as low as possible
(C) be one of the rst to operate its manufacturing
plants at minimum ef cient scale
(D) produce goods of higher quality than those
produced by direct competitors
(E) stockpile raw materials at production sites in
order to ensure a steady ow of such materials
Inference
is question asks for an inference about what
a manufacturer in a capital‐intensive industry
must do to have an advantage over competitors
making similar products. e passage addresses
this question by stating that advantage accrues
to those rms that are the rst to exploit the
full potential of optimally sized, technologically
sophisticated plants. In this context, exploiting
the full potential of such plants means operating
them at minimum e cient scale . Based on the
de nition in the rst paragraph, this means that
the plant must have an output of such a size that
the cost per unit of output is at a minimum.
A e passage says that for new capital‐
intensive rms to dominate the market, it is
not enough for them to have optimally sized
plants; the plants must also be operated in a
way that fully exploits their potential.
B While keeping xed and sunk costs low
would obviously help keep overall costs
low, the passage does not suggest that this
is decisive in enabling a rm to have an
advantage over competitors.
C Correct. Being among the rst
manufacturers to operate plants at minimum
e cient scale means that those plants
are being exploited to their full potential.
is strategy would most likely give such
manufacturers a decisive advantage over new
rms hoping to compete e ectively.
D e passage does not discuss the quality of
goods made by manufacturers.
E e passage does not suggest that stockpiling
raw materials is the most e cient way to
ensure a steady ow of raw materials into the
manufacturing process, though the passage
states that such a steady ow is a factor in
achieving minimum e cient scale.
e correct answer is C.
457. The passage suggests that which of the following is
true of a manufacturer’s xed and sunk costs?
(A) The extent to which they are determined
by market conditions for the goods being
manufactured is frequently underestimated.
(B) If they are kept as low as possible, the
manufacturer is very likely to realize signi cant
pro ts.
(C) They are the primary factor that determines
whether a manufacturer will realize economies of
scale.
(D) They should be on a par with the xed and sunk
costs of the manufacturer’s competitors.
(E) They are not affected by uctuations in a
manufacturing plant’s throughput.
Inference
is question asks about what the passage implies
about xed and sunk costs. e passage states that
when production declines due to certain factors,
such costs remain at the same level (which may
be high), and the cost per unit produced ( unit
costs ) rises sharply.
A e passage discusses the impact of market
conditions on determining what the optimal
size of a manufacturing plant is (which
a ects xed and sunk costs). But it makes
no claim about the frequency with which
such an impact is “underestimated.”
B e passage emphasizes that failing to
keep throughput at an e ciently high level
reduces pro tability because that failure
results in increased cost per unit (to which,
of course, the plant’s xed and sunk costs
contribute). But the passage does not claim
that keeping aggregate xed and sunk costs
very low is necessary in order to have the
most competitive production operation.
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
454
C e passage emphasizes that the crucial
factor in achieving economies of scale
is e cient operation of the production
facilities, not the size of the rm’s xed
and sunk costs (even though such costs are
clearly in part determined by the size and
design of the production facilities).
D While a manufacturer’s xed and sunk
costs may be on a par with those of the
manufacturer’s competitors, the passage
provides no grounds for inferring that there
is any need for them to be (for example,
physical plants that employ di erent
technologies may have di erent price tags).
E Correct. According to the passage,
“throughput” refers to the ow of materials
through a plant. is ow can vary as a
result of various factors, but xed and
sunk costs— nancial resources already
committed—remain the same regardless of
such variation.
e correct answer is E.
458. In the context of the passage as a whole, the second
paragraph serves primarily to
(A) provide an example to support the argument
presented in the rst paragraph
(B) evaluate various strategies discussed in the rst
paragraph
(C) introduce evidence that undermines the
argument presented in the rst paragraph
(D) anticipate possible objections to the argument
presented in the rst paragraph
(E) demonstrate the potential dangers of a
commonly used strategy
Evaluation
is question asks about the rhetorical
function of the second paragraph. While the
rst paragraph argues that a crucial factor in
achieving economies of scale is intangible capital,
or organized human capabilities, the second
paragraph uses the example of new capital‐
intensive manufacturing industries to help show
that this is indeed the case.
A Correct. e second paragraph provides
an example that illustrates the claims
made in the rst paragraph. It discusses
the way in which intangible capital—e.g.,
distribution networks, marketing systems,
smooth production processes, and quali ed
management teams—enables manufacturers
in new capital‐intensive manufacturing
industries to realize economies of scale and
achieve market dominance.
B e second paragraph does, in a sense,
“evaluate” investment in intangible capital:
it suggests that such investment is necessary.
However, investment in intangible capital is
the only strategy it discusses.
C e second paragraph supports rather than
undermines the rst paragraph’s argument.
D Nothing in the second paragraph suggests
that there are, or could be, any objections to
the rst paragraph’s argument.
E e second paragraph discusses the
potential positive outcomes of investing
in intangible capital. It suggests that there
might be negative consequences to not
making such investments, but it does not
indicate that avoiding such investments is a
commonly used strategy.
e correct answer is A.
459. The passage LEAST supports the inference that a
manufacturer’s throughput could be adversely
affected by
(A) a mistake in judgment regarding the selection of
a wholesaler
(B) a breakdown in the factory’s machinery
(C) a labor dispute on the factory oor
(D) an increase in the cost per unit of output
(E) a drop in the ef ciency of the sales network
Application
is question may be best approached by using
an elimination strategy— rst nding the four
choices that can reasonably be inferred from the
passage, and then checking to make sure that the
remaining choice cannot reasonably be inferred.
is requires understanding the information the
passage gives about throughput, then making
inferences about what can cause throughput to
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455
drop. e passage de nes throughput generally
as the ow of materials through a plant and goes
on to explain that it involves coordination of the
production process itself, as well as obtaining
materials from suppliers and marketing and
distributing the manufactured products. Anything
that damages this ow of materials and products
would be said to have an adverse e ect on
throughput.
A Making a poor judgment about a wholesaler
would most likely have an adverse e ect on
throughput, in that it could a ect the ow of
output to wholesalers and nal consumers .
B A breakdown in machinery would likely
fall into the category of problems on the
factory oor mentioned in the passage and
would likely prove damaging to throughput
because of its e ect on the production
process itself.
C A labor dispute would also likely fall into
the category of problems on the factory
oor mentioned in the passage and would
probably cause a decline in production and
thus adversely a ect throughput.
D Correct. e passage emphasizes that
changes in throughput can cause increases
or decreases in costs per unit. But the
passage is not committed to any claims
about how changes in costs per unit might
a ect throughput.
E e passage suggests that ine cient
sales networks could cause a decline
in production. us a decrease in sales
e ciency would most likely adversely a ect
a manufacturer’s ability to provide goods to
consumers, and thus would create problems
with throughput.
e correct answer is D.
460. The primary purpose of the passage is to
(A) point out the importance of intangible capital for
realizing economies of scale in manufacturing
(B) show that manufacturers frequently gain a
competitive advantage from investment in large
manufacturing facilities
(C) argue that large manufacturing facilities often
fail because of inadequate investment in both
tangible and intangible capital
(D) suggest that most new industries are likely
to be dominated by rms that build large
manufacturing plants early
(E) explain why large manufacturing plants usually
do not help manufacturers achieve economies of
scale
Main idea
is question depends on understanding the
passage as a whole. In general, it makes an
argument for investing in intangible capital as
a way for manufacturers to realize economies
of scale, and it supports its argument with an
example.
A Correct. e passage focuses on intangible
capital as a crucial factor in realizing
economies of scale.
B According to the passage, manufacturers
gain competitive advantage by building
plants of optimal size that they then fully
exploit; nothing in the passage suggests that
large plants are frequently optimal.
C e passage assumes that manufacturers
invest appropriately in tangible capital and
argues that it is important for them to invest
in intangible capital as well.
D e passage states that new capital‐intensive
manufacturing industries are dominated
not by rms that are the rst to build large
plants, but by rms that exploit the full
potential of their plants.
E e passage indicates that economies of
scale can be achieved in plants of optimal
size. e passage does not suggest that large
plants cannot be optimal.
e correct answer is A.
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
456
Questions 461–466 refer to the passage on page 390.
461. The primary purpose of the passage is to
(A) describe the development of new techniques that
may help to determine the driving force behind
population cycles in lepidoptera
(B) present evidence that refutes a particular theory
about the driving force behind population cycles
in lepidoptera
(C) present a hypothesis about the driving force
behind population cycles in lepidoptera
(D) describe the uctuating patterns of population
cycles in lepidoptera
(E) question the idea that a single driving force is
behind population cycles in lepidoptera
Main idea
is question depends on understanding the
passage as a whole in order to identify its purpose.
e rst paragraph de nes population cycles of
lepidoptera and discusses some ways those cycles
have been studied. It suggests that a particular
agent may regulate these cycles. e second
paragraph describes a candidate for this agent:
nuclear polyhedrosis viruses. e third paragraph
explains why this hypothesis is compelling.
A e passage mentions new techniques in
molecular biology, but it does so in order to
explain why a particular candidate for the
agent behind population cycles has come to
light.
B e theory the passage presents is that
there is a driving force behind lepidoptera
population cycles. It does not refute this
theory; rather, it o ers a convincing case for
nuclear polyhedrosis viruses as that force. It
also discusses some previous approaches to
seeking plausible hypotheses but does not
focus on refuting any particular hypothesis.
C Correct. e passage is primarily concerned
with presenting the hypothesis that nuclear
polyhedrosis viruses are the driving force
behind lepidoptera population cycles.
D e rst paragraph describes the uctuating
patterns of lepidoptera population cycles,
but it does so to explain what population
cycles are, so that it can then go on to
attempt to account for those cycles.
E e passage is concerned with making a
case for nuclear polyhedrosis viruses as
the driving force behind at least some
lepidoptera population cycles, not with
questioning the idea that there is a driving
force.
e correct answer is C.
462. It can be inferred from the passage that the mortality
caused by agents such as predatory birds or parasites
was measured in an attempt to
(A) develop an explanation for the existence of
lepidoptera population cycles
(B) identify behavioral factors in lepidoptera that
affect survival rates
(C) identify possible methods for controlling
lepidoptera population growth
(D) provide evidence that lepidoptera populations
are self‐regulating
(E) determine the life stages of lepidoptera at which
mortality rates are highest
Inference
e passage states that mortality caused by
various agents, birds and parasites among them,
was measured because this was the common
approach to studying causes of population cycles.
is in turn suggests that those scientists engaged
in such measuring in the case of lepidoptera
were attempting to come up with a de nitive
explanation for why those lepidoptera population
cycles occurred.
A Correct. Measuring mortality caused by
various agents was part of the attempt
to determine the driving force behind
lepidoptera population cycles.
B e passage does not indicate that
behavioral factors in lepidoptera are related
to their mortality as caused by agents such
as predatory birds or parasites.
C e passage is concerned not with
controlling lepidoptera population growth,
but rather with determining why population
cycles occur.
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457
D According to the information in the
passage, scientists sought to measure
mortality caused by particular agents in
order to determine the driving force behind
lepidoptera population cycles. In suggesting
that mortality caused by these agents is
not that force, the measurements may have
indicated that the cycles could be self‐
regulating, but they were not undertaken in
order to provide such evidence.
E e passage discusses mortality primarily
in the caterpillar stage and does not suggest
that any research was directed toward
comparing caterpillar mortality rates with
mortality rates in other life stages of the
insects.
e correct answer is A.
463. Which of the following, if true, would most weaken the
author’s conclusion in lines 18–22?
(A) New research reveals that the number of species
of birds and parasites that prey on lepidoptera
has dropped signi cantly in recent years.
(B) New experiments in which the habitats of
lepidoptera are altered in previously untried ways
result in the shortening of lepidoptera population
cycles.
(C) Recent experiments have revealed that the
nuclear polyhedrosis virus is present in a number
of predators and parasites of lepidoptera.
(D) Differences among the habitats of lepidoptera
species make it dif cult to assess the effects of
weather on lepidoptera population cycles.
(E) Viral disease is typically observed in a large
proportion of the lepidoptera population.
Evaluation
e sentence in question presents the author’s
conclusion that lepidoptera populations may be
self‐regulating or regulated by something more
closely connected to the insects than predatory
birds or parasites are. To weaken that conclusion
requires weakening its support, namely, that
mortality caused by predators and parasites seems
not to a ect population cycles, and that changing
habitats and reducing populations has not altered
population cycles either.
A A drop in birds and parasites preying on
lepidoptera would not weaken the author’s
conclusion; mortality caused by these
predators has not a ected population cycles.
B Correct. New experiments involving
changes in habitat that did succeed in
altering population cycles would suggest
that the populations are not in fact self‐
regulating, and that the search for another
cycle‐altering agent may be unnecessary.
C is nding would support the idea that
the nuclear polyhedrosis virus is responsible
for population cycles—that is, that the virus
is the closely connected agent the author
concludes is responsible.
D e suggestion that the e ects of weather
may not have been adequately assessed is
remotely relevant to the author’s conclusion,
but the mere di culty of assessing the
e ects provides no positive reason to
suppose that weather may be the cause of
the cycles. On the other hand, answer choice
B does o er evidence for an alternative
explanation.
E Viral disease is what the author ultimately
suggests is the agent that drives the
lepidoptera population cycles in question.
e wide presence of viruses in lepidoptera
could help support the author’s conclusion.
e correct answer is B.
464. According to the passage, before the discovery of
new techniques for detecting viral DNA, population
ecologists believed that viral diseases
(A) were not widely prevalent among insect
populations generally
(B) affected only the caterpillar life stage of
lepidoptera
(C) were the driving force behind lepidoptera
population cycles
(D) attacked already declining caterpillar populations
(E) infected birds and parasites that prey on various
species of lepidoptera
7.6 Reading Comprehension Answer Explanations
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Supporting Idea
is question addresses what the passage states
directly about population ecologists’ beliefs
regarding viral diseases prior to the discovery
of new viral DNA–detection techniques. e
second paragraph of the passage states that these
ecologists believed viral disease contributed to
population decline that was already underway
rather than initiating it.
A e second paragraph states that viral
disease had been reported; thus, population
ecologists were aware of its existence in
insect populations. e passage is consistent
with ecologists having believed that it was
prevalent.
B e passage focuses mainly on the
caterpillar life stage of lepidoptera, but there
is nothing to suggest that scientists held
particular beliefs regarding viral diseases’
restriction to that life stage.
C It is after, not before, the discovery of new
techniques for detecting viral DNA when
populations ecologists came to believe that
such diseases were the driving force behind
the population cycles.
D Correct. As stated in the passage,
population ecologists believed that viral
diseases contributed to already occurring
population decline.
E e passage does not discuss whether
viral diseases may infect any lepidoptera
predators.
e correct answer is D.
465. According to the passage, nuclear polyhedrosis
viruses can remain virulent in the environment only
when
(A) the polyhedrin protein crystals dissolve
(B) caterpillar populations are in decline
(C) they are present in large numbers
(D) their concentration in a particular area remains
low
(E) they are sheltered from direct sunlight
Supporting Idea
e passage states in the second paragraph that
these viruses remain virulent for many years if
they are protected from direct sunlight. ey are
embedded in crystals of polyhedrin protein.
A e viruses remain virulent partially because
of their being contained in polyhedrin
protein crystals. ey would most likely not
remain virulent if those crystals dissolved.
B e viruses remain virulent even when
caterpillar populations are not in decline;
that is how the viruses initiate new
population declines.
C According to the passage, viral DNA has
been detected in the environment at low
concentrations, yet the viruses are still
virulent. us, they need not be present in
large numbers.
D Nothing in the passage indicates that the
concentration of these viruses must be low
for them to be virulent.
E Correct. e passage says that if the viruses
are protected from direct sunlight, they
remain virulent for many years. e context
strongly suggests that if they are not so
protected, they do not remain virulent.
e correct answer is E.
466. It can be inferred from the passage that while inside its
polyhedrin protein crystals, the nuclear polyhedrosis
virus
(A) is exposed to direct sunlight
(B) is attractive to predators
(C) cannot infect caterpillars’ cells
(D) cannot be ingested by caterpillars
(E) cannot be detected by new techniques of
molecular biology
Inference
e passage indicates that the polyhedrin protein
crystals protect the nuclear polyhedrosis virus when
it is in the environment. When a caterpillar ingests
those crystals, they dissolve. at releases the virus,
whereupon it infects the caterpillar’s cells. us it is
reasonable to infer that the virus must be released
from the crystals before it can infect the caterpillar.
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A e passage states that nuclear polyhedrosis
viruses remain embedded in polyhedrin
protein crystals if protected from direct
sunlight, not that the virus is exposed to
light when it is in the protein crystals.
B Nothing in the passage indicates that any
organism preys on the virus itself or that it
attracts predators to caterpillars that it infects.
C Correct. e virus must be released from the
crystals before it can infect caterpillars’ cells.
D e passage states that caterpillars ingest
the polyhedrin protein crystals.
E According to the passage, new techniques
of molecular biology enable the detection of
viral DNA in the environment. e nuclear
polyhedrosis virus persists in the environment
inside protein crystals. e passage suggests
that the new techniques are able to detect the
virus inside its crystals but does not provide
any evidence about whether they detect it
directly or infer its presence indirectly.
e correct answer is C.
Questions 467–470 refer to the passage on page 392.
467. According to the passage, which of the following is
true of plant antiherbivore chemistry?
(A) Changes in a plant’s antiherbivore chemistry may
affect insect feeding behavior.
(B) A plant’s repellent effects often involve
interactions between gum and resin.
(C) A plant’s antiherbivore responses assist in
combating bacterial infections.
(D) Plant antiherbivore chemistry plays only a minor
role in the coevolution of plants and insects.
(E) Researchers rst studied repellent effects in
plants beginning in the 1950s.
Supporting ideas
is question addresses what the information in
the passage indicates about plant antiherbivore
chemistry—that is, plants’ chemical defenses
against herbivore attacks. e second paragraph
of the passage cites the views of various
scientists regarding the possible role of resin
in antiherbivore chemistry; plants could have
evolved resin speci cally to repel insects.
A Correct. According to the second
paragraph, various scientists have suggested
that a change in antiherbivore chemistry,
here speci cally involving resin, could repel
insects; alternatively, some insects could
have been attracted to resin, feeding more
heavily on plants that produced it. Other
researchers have suggested that even if resin
does not directly repel or attract insects,
it may indirectly a ect insect-feeding
behavior by mediating changes in plants’
antiherbivore chemistry.
B e rst paragraph states that plants
produce gum in response to bacterial
infections. Although this does not rule out
the hypothesis that gum also contributes to
plants’ antiherbivore chemistry, the passage
provides no evidence that it does so.
C According to the passage, a plant’s
antiherbivore responses have developed to
combat predators, such as insects, that eat
plants. e passage provides no evidence
that such responses also combat bacterial
infections.
D e second paragraph indicates that plant
antiherbivore chemistry plays a major
role in the discipline of chemical ecology,
and chemical ecology concerns itself with
coevolution of plants and insects.
E According to the passage, it was in the
1950s that entomologists began discussing
resin’s possible role in repelling and
attracting insects. e passage does not
suggest that this marked the beginning
of their study of repellent e ects more
generally.
e correct answer is A.
468. Of the following topics, which would be most likely to
be studied within the discipline of chemical ecology as
it is described in the passage?
(A) Seeds that become attached to certain insects,
which in turn carry away the seeds and aid in
the reproductive cycle of the plant species in
question
(B) An insect species that feeds on weeds
detrimental to crop health and yield, and how
these insects might aid in agricultural production
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(C) The effects of deforestation on the life cycles
of subtropical carnivorous plants and the insect
species on which the plants feed
(D) The growth patterns of a particular species of
plant that has proved remarkably resistant to
herbicides
(E) Insects that develop a tolerance for feeding on a
plant that had previously been toxic to them, and
the resultant changes within that plant species
Application
e discipline of chemical ecology, as it is
described in the passage, deals with how plants
use chemicals to interact with other organisms—
in particular, how they defend against attack—
and how those interactions have evolved. To be
studied within that discipline, a speci c topic
would need to address some aspect of that
chemical interaction.
A e passage provides no reason to suppose
that the topic of seeds and how they travel
would be studied within chemical ecology,
given that it does not discuss how chemicals
might be involved in the reproductive cycle.
B e passage provides no indication that
chemical ecology would be concerned with
how weed-destroying insects would aid
agricultural production.
C e passage provides no indication that
deforestation would involve plant chemicals
or that its e ects would be studied in
chemical ecology .
D e passage provides no indication that a
plant’s resistance to herbicides would be
studied in chemical ecology, but the passage
does suggest that the focus of chemical
ecology is on how plants chemically interact
with other organisms.
E Correct. Chemical ecology developed to
deal with the interdependence between
plants and insects. Insects’ developing
a tolerance for feeding on a once-toxic
plant, and the plants’ resultant changes, is
a situation of just such interdependence:
plants and insects coevolving.
e correct answer is E.
469. The author refers to “bacterial infections” (see line 11)
most likely in order to
(A) describe the physiological function that gum
performs in plants
(B) demonstrate that sap is not the only substance
that is transported through a plant’s tissues
(C) explain how modern chemical analysis has been
used to clarify the function of resin
(D) show that gum cannot serve as an effective
defense against herbivores
(E) give an example of how confusion has arisen
with regard to the nature of resin
Evaluation
e author mentions bacterial infections in the
rst paragraph as the reason why plants produce
the substance known as gum.
A Correct. e author states directly that
plants produce gum in response to bacterial
infections.
B e author states directly that sap is
transported through plant tissues. e
passage does not address the question of
whether bacterial infections or anything
related to them are similarly transported.
C e passage indicates that rigorous chemical
analysis is now available, but scientists still
do not know resin’s function. e reference
to bacterial infections is related to gum, not
resin.
D e reference to bacterial infections
indicates the actual purpose served by gum;
it does not function to show ways in which
gum is inadequate.
E Gum itself serves as an example of the
confusion surrounding the nature of
resin; bacterial infections, to which gum
production is a response, do not serve as
that example.
e correct answer is A.
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470. The author of the passage refers to Pliny most
probably in order to
(A) give an example of how the nature of amber has
been misunderstood in the past
(B) show that confusion about amber has long been
more pervasive than confusion about resin
(C) make note of the rst known reference to amber
as a semiprecious gem
(D) point out an exception to a generalization about
the history of people’s understanding of amber
(E) demonstrate that Pliny believed amber to be a
mineral
Evaluation
e passage states generally that amber has been
widely misunderstood but cites Pliny as noting
correctly, in the rst century, that amber resulted
from a substance discharged by trees.
A Pliny’s observation was, according
to the author, accurate and not a
misunderstanding.
B e author equates confusion about amber
with confusion about resin; the reference
to Pliny does not indicate which of the
two, amber or resin, has been more widely
misunderstood.
C e author indicates that others, not Pliny,
mischaracterized amber as a semiprecious
gem—and when that mischaracterization
rst occurred is not identi ed.
D Correct. Pliny’s recognition that amber
came from a substance discharged by
trees stands, in the author’s account, as
an exception to the widespread incorrect
identi cations of the substance.
E Others held the belief that amber was a
mineral. e passage indicates that Pliny
recognized that amber came from trees but
provides no evidence that he also considered
it a mineral.
e correct answer is D.
Questions 471–473 refer to the passage on page 394.
471. The primary purpose of the passage is to
(A) compare the impact of the Great Depression on
Latin America with its impact on the United States
(B) criticize a school of economic historians for
failing to analyze the Great Depression in Latin
America within a global context
(C) illustrate the risks inherent in comparing different
types of economic enterprises to explain
economic phenomena
(D) call into question certain scholars’ views concerning
the severity of the Great Depression in Latin America
(E) demonstrate that the Great Depression had
a more severe impact on industry in Latin
American than in certain other regions
Main idea
is question depends on understanding the
passage as a whole. e passage rst describes the
view of many economic historians of the 1980s. It
next describes the evidence on which that view is
based. e remainder of the passage raises issues
about the rationale for that view.
A e comparison between Latin America
and the United States is only a small part of
a larger argument analyzing studies of the
Great Depression in Latin America.
B e passage does not discuss a global
context for the Great Depression.
C e passage does not primarily aim to
illustrate risks that may be generally
inherent in explaining economic
phenomena.
D Correct. e passage claims that certain
scholars underestimate the severity of the
Great Depression in Latin America.
E e passage does not claim that the impact
of the Great Depression on Latin American
industry was generally more severe than its
impact on industry elsewhere.
e correct answer is D.
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472. Which of the following conclusions about the Great
Depression is best supported by the passage?
(A) It did not impede Latin American industrial
growth as much as historians had previously
thought.
(B) It had a more severe impact on the Brazilian and
the Mexican textile industries than it had on Latin
America as a region.
(C) It affected the Latin American textile industry
more severely than it did any other industry in
Latin America.
(D) The overall impact on Latin American industrial
growth should be reevaluated by economic
historians.
(E) Its impact on Latin America should not be
compared with its impact on the United States.
Inference
is question asks which conclusion is most
strongly supported by the passage. e passage
presents the rationale of some historians for their
conclusion that the Great Depression did not
signi cantly interfere with economic growth in
Latin America. It then critiques that rationale
and conclusion. By questioning the historians’
claims, the passage suggests that a reevaluation of
the Great Depression’s e ect on Latin America is
needed.
A e passage does not signi cantly support
this. e passage indicates that, in fact, the
Great Depression impeded Latin American
economic development more than some
historians had thought.
B e passage does not signi cantly support
this. e passage does not compare the
impact on the Brazilian and Mexican
textile industries to the impact on the Latin
American region.
C e passage does not signi cantly support
this. e passage does not compare the
e ect of the Great Depression on the textile
industry to its e ect on other industries.
D Correct. As presented in the passage, the
passage author’s critique of the historians’
rationale for their claims provides signi cant
support for the conclusion that their claims
should be reevaluated.
E e passage does not signi cantly support
the claim that the comparison in question
should not be made.
e correct answer is D.
473. Which of the following, if true, would most strengthen
the author’s assertion regarding economic indicators in
lines 25–27 ?
(A) During an economic depression, European textile
manufacturers’ pro ts rise while their industrial
output remains steady.
(B) During a national economic recession, United
States microchips manufacturers’ pro ts rise
sharply while United States steel manufacturers’
pro ts plunge.
(C) During the years following a severe economic
depression, textile manufacturers’ output levels
and pro t levels increase in Brazil and Mexico
but not in the rest of Latin America.
(D) Although Japanese industry as a whole recovers
after an economic recession, it does not regain
its previously high levels of production.
(E) While European industrial output increases in the
years following an economic depression, total
output remains below that of Japan or the United
States.
Application
e question involves applying information
from outside the passage to a claim made by the
author. e text in lines 25–27 asserts that broad
economic indicators pertaining to a nation or
region can obscure di erences between individual
rms or industries within that nation or region.
e question asks which evidence would most
strengthen the support for that conclusion.
A is refers only to the relationship between
a single industry’s pro ts and its output, not
to general economic indicators.
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B Correct. e phrase a national recession
refers to a general economic indicator.
Suppose that in a situation described as a
national recession, one industry (microchip
manufacturing) prospers while another
industry (steel manufacturing) does not.
is would provide some additional support,
over and above that given in the passage, for
the assertion that broad economic indicators
may mask di erences between industries.
C Economic di erences between countries do
not strengthen the support for the author’s
assertion regarding variations among
di erent rms and industries in one country
or region.
D is has no obvious bearing on how
sweeping economic indicators can mask
di erences between industries or enterprises
in a single country or region.
E A comparison of di erent countries does
not pertain to the assertion regarding
variation among rms and industries in the
same country.
e correct answer is B.
Questions 474–477 refer to the passage on page 396.
474. It can be inferred from the passage that a large plant
might have to spend more than a similar but smaller
plant on environmental compliance because the larger
plant is
(A) more likely to attract attention from local
regulators
(B) less likely to be exempt from permit and
reporting requirements
(C) less likely to have regulatory costs passed on to
it by companies that supply its raw materials
(D) more likely to employ older production
technologies
(E) more likely to generate wastes that are more
environmentally damaging than those generated
by smaller plants
Inference
is item depends on understanding the
implications of the passage’s discussion of
di erences between large and small plants. It asks
what might be true of a larger plant that would
compel it to spend more than a smaller plant on
environmental compliance. e passage addresses
this issue by stating that smaller plants are often
not subject to the same permit or reporting
requirements that larger plants are.
A e likelihood of attracting regulatory
attention is discussed only in the context of
comparing plants that are isolated with small
plants that are near large noncompliant
ones. e passage does not suggest that size
is generally the crucial determining factor in
attracting regulatory attention.
B Correct. According to the passage, certain
permit or reporting requirements may
not apply to smaller plants; this suggests
that larger plants are less likely than
smaller plants to be exempt from these
requirements, and thus that the larger plants
would have to spend more to comply.
C e passage does not discuss the passing on
of regulatory costs from suppliers to plants.
D e passage does not suggest that larger
plants are any more likely than smaller
plants to employ older production
technologies.
E e passage does not distinguish between
the types of wastes emitted by larger plants
and those emitted by smaller plants.
e correct answer is B.
475. According to the passage, which of the following
statements about sulfur dioxide and nitrogen oxide
outputs is true?
(A) Older production technologies cannot be
adapted so as to reduce production of these
outputs as waste products.
(B) Under the most recent environmental regulations,
industrial plants are no longer permitted to
produce these outputs.
(C) Although these outputs are environmentally
hazardous, some plants still generate them as
waste products despite the high compliance
costs they impose.
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(D) Many older plants have developed innovative
technological processes that reduce the
amounts of these outputs generated as waste
products.
(E) Since the production processes that generate
these outputs are less costly than alternative
processes, these less expensive processes are
sometimes adopted despite their acknowledged
environmental hazards.
Supporting idea
is item depends on identifying what the
passage states explicitly about outputs of sulfur
dioxide and nitrogen oxide. e passage says that
plants that produce these outputs are those that
use older industrial coal‐ red burners, and that
such plants are subject to extensive compliance
costs imposed by new regulations.
A e passage does not address the question
of whether older production technologies
might be adapted to reduce outputs of sulfur
dioxide and nitrogen oxide.
B e passage states that new regulations have
imposed high compliance costs on companies
that produce sulfur dioxide and nitrogen oxide
outputs, not that these outputs are prohibited.
C Correct. e passage states that some
companies are still using the older kinds
of burners that generate sulfur dioxide
and nitrogen oxide outputs, and that new
regulations have imposed high compliance
costs on these companies.
D e passage does not address the question
of whether older plants have developed new
processes to reduce the amounts of sulfur
dioxide and nitrogen oxide they produce.
E Sulfur dioxide and nitrogen oxide outputs,
the passage suggests, are produced only by
older industrial coal‐ red burners; newer
facilities (using alternative processes) do
not employ this technology, the expense of
which is not mentioned in the passage.
e correct answer is C.
476. Which of the following best describes the relationship
of the statement about large plants (lines 12–17) to
the passage as a whole?
(A) It presents a hypothesis that is disproved later in
the passage.
(B) It highlights an opposition between two ideas
mentioned in the passage.
(C) It provides examples to support a claim made
earlier in the passage.
(D) It exempli es a misconception mentioned earlier
in the passage.
(E) It draws an analogy between two situations
described in the passage.
Evaluation
is question asks about the role played in the
passage by the following statement: Additionally,
large plants can spread compliance costs such as waste
treatment across a larger revenue base; on the other
hand, some smaller plants may not even be subject
to certain provisions such as permit or reporting
requirements by virtue of their size . is statement
describes situations in which compliance costs for
plants of di erent sizes may di er, which serve as
evidence in support of the passage’s main claim:
that environmental regulations do not a ect all
competitors in a given industry uniformly.
A e statement in question is not a
hypothesis; rather, it reports factors that
are known to a ect the varying impact of
environmental regulations.
B is is too vague to be a good description
of the kind of relationship the question
asks about. e statement in question does
present a contrast—it suggests that larger
plants’ compliance costs are lower under
some circumstances, while smaller plants’
compliance costs are lower under other
circumstances. But this purports to state
two facts rather than mere ideas ; they are
contrasting facts but not in any meaningful
sense opposed , since they can easily coexist.
C Correct. e statement provides examples
to support the initial claim made in the
passage that regulatory costs fall unevenly on
competitors in an industry: large plants can
spread compliance costs around, and smaller
plants may not even have to pay certain costs.
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D is statement helps to dispel, not
exemplify, a misconception mentioned
earlier in the passage—i.e., the myth
that environmental regulations a ect all
companies in an industry the same way.
E e statement does not suggest that the
situation of larger and smaller plants is
similar (or analogous) to any other situation
mentioned in the passage.
e correct answer is C.
477. The primary purpose of the passage is to
(A) address a widespread environmental
management problem and suggest possible
solutions
(B) illustrate varying levels of compliance with
environmental regulation among different
corporations
(C) describe the various alternatives to traditional
methods of environmental management
(D) advocate increased corporate compliance with
environmental regulation
(E) correct a common misconception about the
impact of environmental regulations
Main idea
is question depends on understanding the
passage as a whole. Its rst sentence indicates
its main purpose: to dispel a myth about
environmental regulations that is often taken as
fact.
A e passage is not about the management
of any environmental problem, which would
be a problem about how to prevent or undo
damage to the environment. e passage
primarily aims to dispel a belief that the
passage says is widely held by environmental
managers.
B e passage refers to variations in rms’
levels of compliance with environmental
regulations, but its primary purpose is not
to illustrate those varying levels, nor does
it do so.
C e passage suggests that most
environmental managers are mistaken
about a key concept; its primary purpose
is not to describe traditional methods of
environmental management or alternatives to
those traditional methods, nor does it do so.
D e passage takes no position on whether
companies should increase their compliance
with environmental regulation.
E Correct. e passage primarily aims
to dispel the belief that environmental
regulations a ect all companies in an
industry uniformly.
e correct answer is E.
Questions 478–483 refer to the passage on page 398.
478. In the passage, the author is primarily interested in
(A) suggesting an alternative to an outdated
research method
(B) introducing a new research method that calls an
accepted theory into question
(C) emphasizing the instability of data gathered from
the application of a new scienti c method
(D) presenting a theory and describing a new
method to test that theory
(E) initiating a debate about a widely accepted
theory
Main idea
is question concerns the main point of the
passage. A careful examination of the overall
structure of the passage will reveal the main
point. In the rst paragraph, the author brie y
presents Milankovitch’s theory and explains why
it could not be tested early on. In the second
and third paragraphs, the author describes how
a new method allows testing of the theory and
shows how evidence from the testing supports the
theory. While the nal paragraph acknowledges
that other factors should be considered, the
author’s primary interest in this passage is in
presenting Milankovitch’s theory and the recently
discovered method for testing it.
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A A new research method is described, but no
previous method is discussed.
B As described in the passage, the new
method tests and con rms the theory; there
is no mention that the theory is accepted or
that the method casts doubt on it.
C Nothing in the passage suggests that
“instability of data” is an issue.
D Correct. e author presents Milankovitch’s
theory and describes the oxygen isotope
method of testing it.
E e theory is nowhere said to be “widely
accepted” and the author does not debate
the theory.
e correct answer is D.
479. The author of the passage would be most likely to
agree with which of the following statements about the
Milankovitch theory?
(A) It is the only possible explanation for the ice
ages.
(B) It is too limited to provide a plausible explanation
for the ice ages, despite recent research
ndings.
(C) It cannot be tested and con rmed until further
research on volcanic activity is done.
(D) It is one plausible explanation, though not the
only one, for the ice ages.
(E) It is not a plausible explanation for the ice ages,
although it has opened up promising possibilities
for future research.
Application
e author’s reaction to the statements about the
Milankovitch theory must be based on how the
author treats the theory in the passage. e rst,
second, and third paragraphs describe the theory
and the use of a new research method to test the
theory. e passage states that data from these
tests have established a strong connection between
variations in the Earth’s orbit and the periodicity
of the ice ages , suggesting that the author of the
passage believes the theory is plausible. In the
nal paragraph, the author points to other factors
that might be involved, suggesting that the theory
might not provide a complete explanation.
A In the last paragraph, the author suggests
that because there are still other untested
factors that may have e ects on climate,
other explanations are possible.
B ough in the last paragraph the author
points to other factors that may be involved,
these are not presented by the author
as indicating limitations that diminish
the plausibility of the theory—they are
acknowledged merely as possibilities that
are not now understood—and nothing else
in the passage suggests that the theory is
“too limited.”
C e author shows how the theory has been
tested; volcanic activity is not part of this
theory.
D Correct. e author’s presentation of the
theory and the tests of the theory show that
the author nds the theory plausible; the
mention of other factors shows the author
does not think that all other explanations
have been ruled out, even if they are as yet
untested.
E e theory was a plausible explanation from
its beginning, but it was not testable until
recently; scientists would be unlikely to try
to devise means to test a theory that did not
strike them as antecedently plausible.
e correct answer is D.
480. It can be inferred from the passage that the isotope
record taken from ocean sediments would be less
useful to researchers if which of the following were
true?
(A) It indicated that lighter isotopes of oxygen
predominated at certain times.
(B) It had far more gaps in its sequence than the
record taken from rocks on land.
(C) It indicated that climate shifts did not occur
every 100,000 years.
(D) It indicated that the ratios of oxygen 16 and
oxygen 18 in ocean water were not consistent
with those found in fresh water.
(E) It stretched back for only a million years.
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Inference
To make an inference about the isotope record
from ocean sediments, examine what the passage
says about that record. e third paragraph
discusses that record and lists its two advantages.
First, it is a global record with remarkably little
variation in samples from varied locations.
Second, it is more continuous than the record from
rocks. If either of these advantages were not true,
then it is logical to infer that the record would be
less useful.
A According to lines 14–16, the lighter isotope
does predominate; this is part of the record
and does not a ect its usefulness.
B Correct. In lines 37–42, the author states
that an advantage of the ocean record is that
it is a more continuous record than that taken
from rocks on land . If this were not true, the
ocean record would be less useful.
C If the record were to show that the
shifts did not occur every 100,000 years,
Milankovitch’s theory would be weakened.
is impact on the theory does not make
the isotope record less useful to researchers.
e record is useful precisely because it can
o er evidence to con rm or refute such
theories.
D is inconsistency would not a ect the
usefulness of the ocean‐water record.
Researchers would simply need to
accommodate the fresh‐water inconsistency.
E e record would still be useful. Lines
42–46 attest to the establishment of a
pattern based on data from the past several
hundred thousand years .
e correct answer is B.
481. According to the passage, which of the following is true
of the ratios of oxygen isotopes in ocean sediments?
(A) They indicate that sediments found during an
ice age contain more calcium carbonate than
sediments formed at other times.
(B) They are less reliable than the evidence from rocks
on land in determining the volume of land ice.
(C) They can be used to deduce the relative volume
of land ice that was present when the sediment
was laid down.
(D) They are more unpredictable during an ice age
than in other climatic conditions.
(E) They can be used to determine atmospheric
conditions at various times in the past.
Supporting ideas
e phrase according to the passage suggests that
the answer to the question is most likely stated
in the passage. Lines 12–14 state that the relative
volume of land ice can be deduced from the ratio
of oxygen 18 to oxygen 16 in ocean sediments.
A ere is no evidence in the passage about
this point.
B e ocean record is described in lines 38–39
as more continuous , so it is unlikely to be less
reliable. In any case, reliability is not discussed.
C Correct. Lines 12–14 explain that the land‐
ice volume for a given period can be deduced
from the ratio of two oxygen isotopes.
D ere is no evidence in the passage to
support this statement.
E e passage does not discuss the use of this
record in determining past atmospheric
conditions.
e correct answer is C.
482. It can be inferred from the passage that precipitation
formed from evaporated ocean water has
(A) the same isotopic ratio as ocean water
(B) less oxygen 18 than does ocean water
(C) less oxygen 18 than has the ice contained in
continental ice sheets
(D) a different isotopic composition than has
precipitation formed from water on land
(E) more oxygen 16 than has precipitation formed
from fresh water
Inference
Any inference about precipitation from evaporated
ocean water needs to be based on what the passage
says. Lines 20–22 show that heavier isotopes tend to
be left behind when water evaporates from the ocean
surfaces . erefore, the evaporated water would
contain less oxygen 18 and the remaining ocean
water would contain more. It is logical to infer
that precipitation formed from this evaporated
water would also contain less oxygen 18.
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A Lines 20–24 explain that the water
remaining in the ocean after evaporation has
more oxygen 18.
B Correct. Since the heavier isotopes tend
to be left behind , there will be less oxygen
18 in the evaporated water and in the
precipitation that forms from it.
C e passage suggests that the ocean
water evaporates and through subsequent
precipitation helps form the ice sheets, so
the amount of oxygen 18 in the ice sheets
should be similar to the amount in the
precipitation formed from the evaporated
water.
D e passage does not discuss precipitation
formed from water on land.
E e passage does not discuss precipitation
formed from fresh water.
e correct answer is B.
483. It can be inferred from the passage that calcium
carbonate shells
(A) are not as susceptible to deterioration as rocks
(B) are less common in sediments formed during an
ice age
(C) are found only in areas that were once covered
by land ice
(D) contain radioactive material that can be used to
determine a sediment’s isotopic composition
(E) re ect the isotopic composition of the water at
the time the shells were formed
Inference
Any inference about calcium carbonate shells
needs to be based on what the passage says about
these shells. Lines 24–32 explain the role of these
shells in forming sediments and establishing a
chronology for ice ages. e shells were constructed
with oxygen atoms drawn from the surrounding
ocean . Lines 29–32 make it clear that if the
sediments reveal a higher ratio of oxygen 18, it
is because more oxygen 18 had been left behind
when the ocean water evaporated and contributed
to the growth of continental ice sheets. It can
thus be inferred that the shells that make up
those sediments must re ect the proportion of
oxygen 18 found in the ocean water at the time
they were formed.
A e only mention of rocks in the passage
is a comparison of “gappiness” of the rock
and sedimentary specimen records in lines
38–39; this information does not allow
any rm inference to be made with respect
to relative susceptibility to deterioration,
though a more continuous record might
be the result of less susceptibility to
deterioration.
B e passage does not make any reference to
the relative abundance of these shells during
ice ages; no such inference can be drawn.
C e only information in the passage that
might support this statement is found in
lines 29–32, but that information, about
the correlation between oxygen ratios in
sediment specimens and land ice, describes
a relation that implies nothing about
distributions of such specimens.
D ough the passage does indirectly indicate
that the shells contained radioactive
material, nothing in the passage suggests
that radioactive material is used to
determine isotopic composition.
E Correct. e passage explains that oxygen
atoms in the surrounding water are one of
the building blocks of calcium carbonate
shells. e isotopic composition of the
surrounding water changes during the ice
age cycles, so it is logical that the isotopic
composition of the shells will change
depending on when they were formed.
e correct answer is E.
Questions 484–489 refer to the passage on page 400.
484. The primary purpose of the passage is to
(A) examine two sides of a historiographical debate
(B) call into question an author’s approach to a
historiographical debate
(C) examine one author’s approach to a
historiographical debate
(D) discuss two authors’ works in relationship to a
historiographical debate
(E) explain the prevalent perspective on a
historiographical debate
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Main idea
is question requires understanding what the
passage as a whole is attempting to do. e passage
opens by introducing two books published in
1984 that both concern the history of women in
the United States. e passage then makes it clear
that one book deals directly (line 15) with the issue
of women’s status, while the other does not. e
passage then goes on to discuss the perspective
that each book takes and what each book has to
o er for an assessment of women’s status in the
eighteenth and nineteenth centuries.
A e two books discussed in the passage
do not take di erent sides on a particular
debate but rather are described as being
more or less useful to the debate itself.
B e passage focuses on how two di erent
books contain information useful to a particular
historiographical debate but does not call into
question the approach of either book.
C e passage focuses on two authors’ works,
not one.
D Correct. e passage discusses what two
di erent books have to o er in relation to a
particular historiographical debate.
E e passage does not describe any
perspective on a particular historiographical
debate as being more prevalent than any
other.
e correct answer is D.
485. The author of the passage mentions the supervision of
schools primarily in order to
(A) remind readers of the role education played in
the cultural changes of the nineteenth century in
the United States
(B) suggest an area in which nineteenth‐century
American women were relatively free to exercise
power
(C) provide an example of an occupation for which
accurate data about women’s participation are
dif cult to obtain
(D) speculate about which occupations were
considered suitable for United States women of
the nineteenth century
(E) illustrate how the answers to questions about
women’s status depend on particular contexts
Evaluation
Answering this question depends on
understanding what role a particular piece of
information plays in the passage as a whole. e
author implicitly supports Lebsock’s contention
(beginning at line 20) that di erent frames of
reference can produce di erent perspectives
on the debate about women’s status in the
eighteenth and nineteenth centuries. e author
then summarizes di erent contexts cited by
Lebsock to support the contention about frames
of reference. As part of this summary, the author
refers to supervising schools (lines 24–25) as an
example of a job that apparently showed women
losing power.
A e passage does not discuss the role of
education in the nineteenth century.
B e passage does mention some ways in
which, according to Lebsock, women …
gained power (lines 25–26) in the nineteenth
century, but supervising schools is not among
them.
C e passage does not discuss the di culty of
obtaining data about particular occupations.
D e passage makes no judgments about
the suitability for women of any jobs in the
nineteenth century.
E Correct. e passage mentions supervising
schools as part of an illustration of Lebsock’s
claim that the debate about women’s status
depends on the context being examined.
e correct answer is E.
486. With which of the following characterizations of
Lebsock’s contribution to the controversy concerning
women’s status in the nineteenth‐century United States
would the author of the passage be most likely to agree?
(A) Lebsock has studied women from a formerly
neglected region and time period.
(B) Lebsock has demonstrated the importance of
frame of reference in answering questions about
women’s status.
(C) Lebsock has addressed the controversy by using
women’s current status as a frame of reference.
(D) Lebsock has analyzed statistics about
occupations and property that were previously
ignored.
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(E) Lebsock has applied recent historiographical
methods to the biography of a nineteenth‐century
woman.
Supporting ideas
Answering this question requires recognizing
information explicitly given in the passage.
e passage introduces the work of Lebsock
in line 6 and then goes on to describe several
characteristics of Lebsock’s book. In lines 20–22,
the author introduces Lebsock’s claim that the
historiographical debate about women’s status
is dependent on frame of reference and calls
that claim important; the passage then gives an
example showing how frame of reference a ects
views of women’s status. In so doing, the author
displays an implicit agreement with Lebsock’s
discussion on this point.
A e author of the passage portrays neither
the place nor time period that Lebsock
focuses on as having been neglected by
historians.
B Correct. e author describes as important
Lebsock’s idea that frame of reference
informs the debate about women’s status.
C According to the passage, Lebsock’s book
deals with women’s status in the eighteenth
and nineteenth centuries, not the present
status of women.
D e passage does not mention or imply that
Lebsock analyzed statistics in writing her
book.
E Although the passage does describe
Lebsock’s book as pertaining to an ongoing
historiographical debate, it identi es the
book’s topic as women in one southern
community (lines 7–8), not the life of a
single woman.
e correct answer is B.
487. According to the passage, Lebsock’s work differs from
Buel and Buel’s work in that Lebsock’s work
(A) uses a large number of primary sources
(B) ignores issues of women’s legal status
(C) refuses to take a position on women’s status in
the eighteenth century
(D) addresses larger historiographical issues
(E) fails to provide suf cient material to support its
claims
Supporting ideas
is question asks for recognition of information
contained in the passage. In the rst sentence,
the passage states that Buel and Buel’s work
and Lebsock’s work have contrasting approaches.
e passage then proceeds, using descriptions of
each work’s approach, to illustrate how the works
di er. e passage notes that Buel and Buel’s
work makes little e ort to place its biographical
subject in the context of recent historiography on
women (lines 5–6), whereas Lebsock’s work
attempts to redirect two decades of historiographical
debate about women’s status.
A Primary sources are not mentioned in the
passage in relation to either work discussed.
B e legal status of women is not mentioned
in the passage.
C Lebsock’s work is described in the passage
as attempting to redirect the debate about
women’s status in the eighteenth and
nineteenth centuries.
D Correct. e passage suggests that by
not placing its subject’s story in the
context of historiography, Buel and Buel’s
work does not therefore address larger
historiographical issues, as Lebsock’s does.
E e passage tends to support Lebsock’s
views and does not refer to any lack of
support for the claims made in Lebsock’s
work.
e correct answer is D.
488. The passage suggests that Lebsock believes that
compared to nineteenth‐century American women,
eighteenth‐century American women were
(A) in many respects less powerful in relation to men
(B) more likely to own real estate
(C) generally more economically independent
(D) more independent in conducting their private
lives
(E) less likely to work as school superintendents
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Inference
is question requires making an inference
based on information given in the passage. As
part of the passage’s description of Lebsock’s
contribution to the historiographical debate
about women’s status in the eighteenth and
nineteenth centuries, Lebsock’s conclusions
about women’s autonomy are described. As
part of this description, the passage cites
Lebsock’s conclusion that nineteenth‐century
women lost economic autonomy when
compared to eighteenth‐century women
(lines 17–20).
A e passage states that in many ways
women in the nineteenth century lost power
in relation to men (line 23), which would
imply that in those respects eighteenth-
century women had more power in
relation to men, not less. e only increase
mentioned in nineteenth‐century women’s
power is associated with owning more real
estate.
B e passage states that more nineteenth-
century women owned real estate.
C Correct. As the passage states, Lebsock
concluded that nineteenth‐century women
lost economic autonomy compared to
eighteenth‐century women.
D e passage states that nineteenth‐century
women gained more independence in their
private lives.
E e passage cites school superintendents
as an example of an occupation more
likely to be held by eighteenth‐century
women.
e correct answer is C.
489. The passage suggests that Buel and Buel’s biography
of Mary Fish provides evidence for which of the
following views of women’s history?
(A) Women have lost power in relation to men since
the colonial era.
(B) Women of the colonial era were not as likely to
be concerned with their status as were women in
the nineteenth century.
(C) The colonial era was not as favorable for women
as some historians have believed.
(D) Women had more economic autonomy in the
colonial era than in the nineteenth century.
(E) Women’s occupations were generally more
respected in the colonial era than in the
nineteenth century.
Inference
is question requires understanding what the
passage implies. e approach that Buel and
Buel’s work takes is speci cally described in lines
3–6 and again in lines 28–34. In lines 29–32, the
passage states that Buel and Buel’s work provides
ample raw material for questioning the myth … of a
colonial golden age in the eighteenth century , referring
to a myth about women’s status. In describing this
golden age as a myth fostered by some historians,
the passage suggests that this era was not as
favorable to women as these historians suggest.
A e passage describes Lebsock’s work as
providing such evidence, not Buel and Buel’s
work.
B e passage does not pertain to the level of
concern women had for their status.
C Correct. e nal paragraph of the passage
describes Buel and Buel’s work as providing
material that calls into question claims
that the eighteenth century was especially
favorable to women.
D e passage refers to the economic
autonomy of women in relation to Lebsock’s
work, not Buel and Buel’s work.
E e passage does not refer to whether any
particular occupations held by women were
more respected at one time or another.
e correct answer is C.
Questions 490–492 refer to the passage on page 402.
490. The passage suggests that WIDC differed from WTUL
in which of the following ways?
(A) WIDC believed that the existing safety regulations
were adequate to protect women’s health,
whereas WTUL believed that such regulations
needed to be strengthened.
(B) WIDC believed that unions could not succeed
in pressuring employers to comply with such
regulations, whereas WTUL believed that unions
could succeed in doing so.
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(C) WIDC believed that lead poisoning in white
lead factories could be avoided by controlling
conditions there, whereas WTUL believed that
lead poisoning in such factories could not
be avoided no matter how stringently safety
regulations were enforced.
(D) At the time that the legislation concerning white
lead factories was proposed, WIDC was primarily
concerned with addressing health conditions
in white lead factories, whereas WTUL was
concerned with improving working conditions in
all types of factories.
(E) At the time that WIDC was opposing legislative
attempts to restrict women’s labor, WTUL had
already ceased to do so.
Inference
To answer this question you need to understand
the di erences between WIDC and WTUL
as they are described in the passage. e only
information about WTUL in the passage is that
it had stopped opposing restrictions on women’s
labor in the late 1880s, and that, because existing
safety regulations were not being enforced, it
supported the proposal to prohibit women from
working in white lead factories. WIDC, on the
other hand, was formed in 1892 speci cally
to oppose restrictions on women’s labor, and it
opposed the proposal.
A According to the passage, WIDC did
believe that existing safety regulations, if
enforced, could prevent lead poisoning.
WTUL may or may not have believed
that the safety regulations needed to be
strengthened; all the passage states is that
WTUL did not believe that the safety
regulations were likely to be enforced.
B e passage states that WTUL believed that
because there were no unions to pressure
employers, the employers would not comply
with safety regulations. e passage does not
present any information on which to base a
conclusion about WIDC’s beliefs regarding
union pressure on employers.
C Based on information in the passage, both
WIDC and SPEW believed that enforcing
safety regulations could protect women
against lead poisoning. WIDC supported
SPEW’s position on the matter. WTUL
believed that safety regulations were
unlikely to be enforced because of the lack
of unions.
D e passage states that WIDC viewed the
proposal to restrict women’s employment
in white lead factories as an instance of
legislation designed to limit women’s work
opportunities—precisely the legislation
that WIDC was formed to oppose. us,
WIDC was not primarily concerned with
the factories’ health conditions.
E Correct. WIDC began opposing legislative
attempts to restrict women’s labor in 1892
and continued to do so through at least
1895, when the Home Secretary proposed
prohibiting women from working in white
lead factories. WTUL stopped opposing
restrictions on women’s labor in the late
1880s, before WIDC was even founded.
us, the passage suggests that WTUL had
stopped opposing restrictions on women’s
labor well before WIDC worked to oppose
such legislation.
e correct answer is E.
491. Which of the following, if true, would most clearly
support the contention attributed to SPEW in lines
17–20?
(A) Those white lead factories that most strongly
enforced regulations concerning worker safety
and hygiene had the lowest incidences of lead
poisoning among employees.
(B) The incidence of lead poisoning was much
higher among women who worked in white lead
factories than among women who worked in
other types of factories.
(C) There were many household sources of lead
that could have contributed to the incidence of
lead poisoning among women who also worked
outside the home in the late nineteenth century.
(D) White lead factories were more stringent than
were certain other types of factories in their
enforcement of workplace safety regulations.
(E) Even brief exposure to the conditions typically
found in white lead factories could cause lead
poisoning among factory workers.
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Evaluation
is question requires the reader to nd a
statement that would provide additional support
for the contention made in the following
statement: SPEW contended, and WIDC concurred,
that controllable conditions in such factories were
responsible for the development of lead poisoning.
Information suggesting that when conditions were
controlled, lead poisoning was less likely to develop
would provide support for SPEW’s contention.
A Correct. If incidences of lead poisoning were
low in those factories that enforced hygiene
and safety regulations, that would suggest
that lead poisoning was not an inevitable
result of working in a white lead factory—but
rather that lead poisoning was the result of
poor hygiene and safety practices.
B It would not be particularly surprising
for the incidence of lead poisoning to be
higher among women working in white
lead factories than among women working
in other kinds of factories—but such a
nding would say nothing about whether
controllable conditions had any e ect on the
development of lead poisoning.
C e existence of household sources
of lead that might contribute to lead
poisoning would weaken, not support,
SPEW’s contention that controllable
factory conditions were responsible for the
development of lead poisoning.
D If white lead factories enforced workplace
safety regulations more stringently than did
some other types of factories, it might be the
case that SPEW’s contention was incorrect:
that even controlled conditions could not
prevent a high incidence of lead poisoning.
E If the conditions typically found in white
lead factories were particularly bad with
regard to safety and hygiene, it could
conceivably be the case that SPEW’s
contention was true—that is, that the
conditions that caused lead poisoning
were controllable. But it might also be the
case that an uncontrollable aspect of those
conditions caused lead poisoning. us, this
neither supports nor undermines SPEW’s
contention clearly.
e correct answer is A.
492. The passage is primarily concerned with
(A) presenting various groups’ views of the motives
of those proposing certain legislation
(B) contrasting the reasoning of various groups
concerning their positions on certain proposed
legislation
(C) tracing the process whereby certain proposed
legislation was eventually enacted
(D) assessing the success of tactics adopted by
various groups with respect to certain proposed
legislation
(E) evaluating the arguments of various groups
concerning certain proposed legislation
Main idea
Answering this question depends on identifying
the overall point of the passage. e passage is
mainly concerned with explaining the reasons
behind the positions taken by WIDC and SPEW,
which opposed the proposal to enact legislation
prohibiting women from holding most white lead
factory jobs, and the reasoning of WTUL, which
supported the proposal.
A e passage explains how WIDC viewed
the proposal, but it does not indicate
what any of the groups believed about the
motivations of the Home Secretary, who
made the proposal.
B Correct. e passage contrasts the
reasoning of the WIDC and SPEW, both
of which believed that enforcing safety
regulations would make the proposed
legislation unnecessary, with the reasoning
of WTUL, which thought that safety
regulations were unlikely to be enforced and
thus supported the proposal.
C e passage simply states that the proposal
was eventually enacted; it does not trace the
process by which this occurred.
D e passage implies that WIDC and SPEW
were unsuccessful in their opposition to the
proposed legislation, but it identi es only
one tactic used in opposition to it: SPEW’s
attempt to challenge it by investigating the
causes of lead poisoning.
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E e passage does not evaluate the groups’
arguments concerning the proposed
legislation; rather, it presents those
arguments without comment on their
quality or value.
e correct answer is B.
Questions 493–498 refer to the passage on page 404.
493. The author of the passage refers to Robert Filmer (see
line 9) primarily in order to
(A) show that Royalist ideology was somewhat more
radical than most historians appear to realize
(B) qualify the claim that patriarchalism formed the
basis of Royalist ideology
(C) question the view that most early feminists were
associated with the Royalist faction
(D) highlight an apparent tension between Royalist
ideology and the ideas of early feminists
(E) argue that Royalists held con icting opinions
on issues of family organization and women’s
political rights
Evaluation
is question asks about the role of Filmer in the
passage. e author states that Filmer’s radical
patriarchalism is associated with Royalist ideology
and then goes on to de ne radical patriarchalism
as an ideology that asserts the power of the
king and the male head of the household. Early
feminists, however, questioned the subordination
of women in marriage. us, there seems to be a
con ict between these two sets of ideas.
A Although the passage refers to Filmer’s
view as radical patriarchalism , it provides no
evidence regarding any di erences in the
degrees to which historians consider that
view, or Royalism in general, to be radical.
B Filmer’s work supports the claim that
patriarchalism was the basis of Royalist
ideology; it does not qualify such a claim.
C at Filmer’s approach was one of radical
patriarchalism makes it surprising that early
feminists were associated with the Royalist
faction, but it does not provide any grounds
for questioning whether they were so
associated.
D Correct. ere is apparent tension between
Filmer’s radical patriarchalism, if that is
indeed essential to Royalist ideology, and
the ideas of early feminists, who questioned
such patriarchalism.
E e author refers to Filmer in order to
suggest, initially, a uniformity among
Royalists regarding family and women; it
is only later in the passage that this view
becomes more complicated.
e correct answer is D.
494. The passage suggests which of the following about
the seventeenth‐century English women mentioned
in line 2?
(A) Their status as forerunners of modern feminism
is not entirely justi ed.
(B) They did not openly challenge the radical
patriarchalism of Royalist Filmerian ideology.
(C) Cavendish was the rst among these women to
criticize women’s subordination in marriage and
assert women’s equality with men.
(D) Their views on family organization and women’s
political rights were diametrically opposed to those
of both Royalist and Parliamentarian ideology.
(E) Historians would be less puzzled if more of them
were identi ed with the Parliamentarian side in
the English Civil Wars.
Inference
e rst sentence of the passage refers to women
who are both regarded as forerunners of modern
feminism and identi ed as Royalists. e passage
goes on to suggest that, given Royalist ideology’s
association with Filmer’s radical patriarchalism
(equating absolute power of the king with
absolute power of the male head of household),
it is surprising that feminism would nd any
footing within such an ideology.
A Nothing in the passage disputes the idea
that the seventeenth‐century English
women in question should be considered
the forerunners of modern feminism.
B Gallagher provides the example of Margaret
Cavendish as a writer who did openly
challenge radical patriarchalism—albeit only
in her writings.
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C e passage states that Cavendish had
successors among early feminists, but it does
not indicate whether she herself was the
rst seventeenth‐century English woman to
assert women’s equality.
D e passage does not indicate what the
Parliamentarian view of family organization
and women’s political rights was, so there is
no way to determine whether the Royalist
forerunners of modern feminism were
opposed to that view.
E Correct. e basic puzzle the passage
sets out to solve is why the forerunners
of modern feminism would have been
associated with the Royalist side, which
seems to have been based on radical
patriarchalism. Historians would most likely
have been less surprised if these women had
been identi ed with the Parliamentarian
side, which presumably did not embrace
radical patriarchalism.
e correct answer is E.
495. The passage suggests that Margaret Cavendish’s
decision to become an author was motivated, at least
in part, by a desire to
(A) justify her support for the Royalist cause
(B) encourage her readers to work toward
eradicating Filmerian patriarchalism
(C) persuade other women to break free from their
political and social isolation
(D) analyze the causes for women’s exclusion from
the pursuit of power
(E) create a world over which she could exercise
total control
Inference
is question asks about Margaret Cavendish’s
reasons for becoming an author. e second
paragraph describes her as someone who insisted
that she was a self‐su cient being ; she understood
that, given the real‐world strictures in place, she
could achieve this self‐su ciency in her own
mind and on paper as a writer. So her decision to
become a writer can be inferred to be motivated
by her desire to exercise power and control.
A e passage states that Cavendish justi ed
her being the center of her own universe by
invoking the Royalist gure of the absolute
monarch; there is no suggestion in the
passage that Cavendish felt the need to
justify any support for the actual Royalist
cause.
B e passage gives no direct indication that
Cavendish was even aware of Filmerian
patriarchalism.
C e second paragraph states that
Cavendish’s idea of absolute singularity
carried with it the idea of social and political
isolation; Cavendish was most likely not
motivated by a desire to persuade other
women to break free from such isolation.
D Cavendish took the exclusion of women
from the pursuit of power for granted;
the passage does not suggest that she was
concerned with its causes.
E Correct. According to the passage,
Cavendish considered herself a self‐
su cient being who was at the center of her
own universe; in her writing, she wanted to
create a world in which this was also true.
e correct answer is E.
496. The phrase “a satellite orbiting a dominant male planet”
(lines 41–42) refers most directly to
(A) Cavendish’s concept that each woman is a
sovereign self
(B) the complete political and social isolation of
absolute singularity
(C) the immaterial world that a writer can create on
paper
(D) the absolute subordination of women in a
patriarchal society
(E) the metaphorical gure of the absolute monarch
Evaluation
e phrase in question is a satellite orbiting a
dominant male planet . e passage states that this
was the idea that Cavendish was reacting against;
she preferred instead the idea that she was the
center of her own universe, her own sovereign,
subject to no one.
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
476
A e idea of a satellite orbiting a dominant
male planet refers not to Cavendish’s idea
that each woman is a sovereign self, but
rather to the idea directly opposed to that:
each woman must submit to a dominant
male.
B A satellite orbiting a dominant male planet is
by de nition not isolated, nor is it singular.
C According to the passage, Cavendish wished
to create her own world as a writer so that
she did not have to be a satellite .
D Correct. e phrase refers to the idea
that in a patriarchal society, women are as
satellites to men, who are the dominant
planets.
E While radical patriarchy does equate
the monarch with the male head of the
household, the in question phrase is most
directly about the relationship, under
patriarchy, between women and men.
e correct answer is D.
497. The primary purpose of the passage is to
(A) trace the historical roots of a modern
sociopolitical movement
(B) present one scholar’s explanation for a puzzling
historical phenomenon
(C) contrast two interpretations of the ideological
origins of a political con ict
(D) establish a link between the ideology of
an in uential political theorist and that of a
notoriously eccentric writer
(E) call attention to some points of agreement
between opposing sides in an ideological debate
Main idea
is question asks about the passage as a
whole. e passage is mainly concerned with
outlining Catherine Gallagher’s attempt to
explain why, given Royalist ideology’s apparent
association with radical patriarchalism, Royalist
women o ered feminist critiques of women’s
subordination in marriage and asserted their
equality with men.
A e passage makes no connection between
early feminism and its modern form.
B Correct. e passage presents a puzzling
historical phenomenon, that Royalist
women critiqued patriarchalism, in
the rst paragraph, and then presents
Catherine Gallagher’s explanation for that
phenomenon in the second paragraph.
C While the passage discusses the political
con ict between the Royalists and
Parliamentarians in the English Civil Wars
in the rst paragraph, neither this con ict,
nor its ideological origins are the focus of
the passage. Furthermore, the passage does
not o er any interpretations of the origins
of the con ict.
D e passage attempts to unlink the ideology
of political theorist Robert Filmer and
the eccentric author Margaret Cavendish
by suggesting that Filmer’s radical
patriarchalism was not the only way of
understanding Royalist ideology. Cavendish
provided a di erent understanding entirely.
E While both sides of the ideological debate
did agree on the absolute monarchy, the
passage as a whole does not focus on this
agreement, but rather on the disagreement
about where, theoretically, the idea of
absolute monarchy leads.
e correct answer is B.
498. Which of the following, if true, would most clearly
undermine Gallagher’s explanation of the link between
Royalism and feminism?
(A) Because of their privileged backgrounds,
Royalist women were generally better educated
than were their Parliamentarian counterparts.
(B) Filmer himself had read some of Cavendish’s
early writings and was highly critical of her ideas.
(C) Cavendish’s views were highly individual and
were not shared by the other Royalist women
who wrote early feminist works.
(D) The Royalist and Parliamentarian ideologies
were largely in agreement on issues of family
organization and women’s political rights.
(E) The Royalist side included a sizable minority
faction that was opposed to the more radical
tendencies of Filmerian patriarchalism.
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Inference
is question asks about how to undermine the
way in which Gallagher connects Royalism and
feminism. According to Gallagher, Cavendish’s
work exempli es the connection between these
ideas, because Cavendish took the idea of
absolute monarchy and extended that to the idea
of absolute self, an idea that should, Cavendish
believed, apply to women as well as men.
A Gallagher’s explanation of the link between
Royalism and feminism does not depend
on the education level of Royalist women
relative to Parliamentarian women.
B Filmer most likely would have been critical
of Cavendish’s ideas, had he encountered
them, but the passage does not indicate
that Gallagher’s argument had anything to
do with whether Filmer read Cavendish’s
writings.
C Correct. Gallagher uses Cavendish’s
work to explain how Royalism gave rise
to feminism, but if Cavendish’s views
were completely atypical of other Royalist
women, then those views cannot explain the
link as Gallagher suggests they do.
D e passage states in the rst paragraph that
if the Royalists and Parliamentarians were
in agreement on issues of family organization
and women’s political rights , then feminists
should have been divided between the two
sides—but they were not. So this idea, if
true, would undermine that statement, but
not Gallagher’s argument about the link
between Royalists and feminists.
E If more Royalists were opposed to Filmer’s
radical patriarchalism, then Cavendish’s
writings would seem to be more
representative of tendencies in Royalist
ideology, thus making Gallagher’s case
stronger, not weaker.
e correct answer is C.
Questions 499–503 refer to the passage on page 406.
499. The passage is primarily concerned with
(A) identifying two practices in medical research that
may affect the accuracy of clinical trials
(B) describing aspects of medical research that tend
to drive up costs
(C) evaluating an analysis of certain shortcomings of
current medical research practices
(D) describing proposed changes to the ways in
which clinical trials are conducted
(E) explaining how medical researchers have
traditionally conducted clinical trials and how
such trials are likely to change
Main idea
is question requires an understanding of what
the passage as a whole is doing. e passage
introduces Frazier and Mosteller as proposing
changes to the ways clinical trials in medical
research are currently conducted. e rest of the
passage then describes these proposed changes
together with the support Frazier and Mosteller
provide for adopting these changes.
A e passage identi es practices in medical
research to help illustrate the basis for
Frazier and Mosteller’s proposed changes.
B e passage mentions medical research costs
as one example within the larger description
of Frazier and Mosteller’s proposed changes.
C e passage is not concerned with
evaluating Frazier and Mosteller’s proposed
changes.
D Correct. e passage describes the changes
proposed by Frazier and Mosteller to the
way clinical trials are conducted.
E e passage is not concerned with
establishing the likelihood of any changes to
the way medical research is conducted.
e correct answer is D.
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
478
500. Which of the following can be inferred from the
passage about a study of the category of patients
referred to in lines 20–22 ?
(A) Its ndings might have limited applicability.
(B) It would be prohibitively expensive in its attempt
to create ideal conditions.
(C) It would be the best way to sample the total
population of potential patients.
(D) It would allow researchers to limit information
collection without increasing the risk that
important variables could be overlooked.
(E) Its ndings would be more accurate if it
concerned treatments for a progressive
disease than if it concerned treatments for a
nonprogressive disease.
Inference
is question requires drawing an inference from
information given in the passage. In describing the
proposals put forth by Frazier and Mosteller, the
passage states in lines 15–20 that they propose using
more patients in clinical trials than are currently
being used, and that the trials would thereby obtain
a more representative sample of the total population
with the disease under study . e passage then states
that researchers often restrict (lines 20–22) their
trials to certain types of patients, therefore limiting
the applicability of their ndings.
A Correct. e passage states that the
researchers preferred to restrict the types of
patients used in their studies, thereby using
a less representative sample than if they
used a more inclusive group of patients.
B e passage mentions the added expense of
clinical trials only in relation to data storage,
collection, and analysis.
C e passage describes the category of
patients referred to as restricted and therefore
unrepresentative of the total population.
D While the passage does mention the amount
of data collected about an individual patient,
that topic is not connected to the category of
patients referred to in lines 20–22.
E e passage does not suggest that a study
using the category of patients referred to
would be more e ective in investigating
progressive diseases.
e correct answer is A.
501. It can be inferred from the passage that a study limited
to patients like those mentioned in lines 20–22 would
have which of the following advantages over the kind
of study proposed by Frazier and Mosteller?
(A) It would yield more data and its ndings would be
more accurate.
(B) It would cost less in the long term, though it
would be more expensive in its initial stages.
(C) It would limit the number of variables researchers
would need to consider when evaluating the
treatment under study.
(D) It would help researchers to identify subgroups
of patients with secondary conditions that might
also be treatable.
(E) It would enable researchers to assess the value of
an experimental treatment for the average patient.
Inference
is question requires understanding what the
information in the passage implies. e passage
explains that Frazier and Mosteller’s proposal involves
enrolling more patients in clinical trials (lines 18–19)
than is the case with the category of patients referred
to. e passage then explains that broadening the
range of trial participants would allow an evaluation
of particular treatments under various conditions and
for di erent patient subgroups (line 29). is strongly
suggests that limiting the patients used to those
described in the referred text would limit the number
of variables researchers would need to consider.
A e passage suggests that not limiting the
patients used in clinical trials will yield more
data than restricting them will.
B e passage refers to the costs of clinical trials
only as they concern the collection, storage,
and analysis of data collected from participants.
C Correct. By limiting the patients used to
those having the ailment under study, the
passage suggests that researchers need to
consider fewer variables in their assessment
of a treatment.
D e passage suggests that not limiting the
types of patients used in clinical trials will
better allow researchers to evaluate subgroups.
E e passage suggests that limiting the types of
patients available for clinical trials results in data
for speci c, rather than average, populations.
e correct answer is C.
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479
502. The author mentions patients’ ages (line 32) primarily
in order to
(A) identify the most critical variable differentiating
subgroups of patients
(B) cast doubt on the advisability of implementing
Frazier and Mosteller’s proposals about medical
research
(C) indicate why progressive diseases may require
different treatments at different stages
(D) illustrate a point about the value of enrolling a
wide range of patients in clinical trials
(E) substantiate an argument about the problems
inherent in enrolling large numbers of patients in
clinical trials
Evaluation
Answering this question requires understanding
how a particular piece of information functions in
the passage as a whole. e passage is concerned
with describing the proposals of Frazier and
Mosteller. One of these proposals, described in the
second paragraph, involves broadening the range
of participants used in clinical trials. e passage
states that in following this proposal, Frazier
and Mosteller suggest that the e ectiveness of
treatments can be assessed for di erent patient
subgroups. To a rm the value of broadening the
range of participants, the passage then cites two
examples of criteria by which relevant subgroups
might be identi ed: disease stages and patients’ ages.
A e passage makes no judgment as to the
value of the subgroups it refers to in relation
to broadened participation in clinical trials.
B e passage does not call into question
the potential e ectiveness of Frazier and
Mosteller’s proposals.
C e passage’s example of patients’ ages is
not intended to be causally connected to
its previous example regarding progressive
diseases.
D Correct. Patients’ ages are referred to in the
passage to identify subgroups that could
be evaluated if the range of participants in
clinical trials were broadened.
E e passage refers to patients’ ages in
support of Frazier and Mosteller’s proposal
that more patients be used in clinical trials.
e correct answer is D.
503. According to the passage, which of the following
describes a result of the way in which researchers
generally conduct clinical trials?
(A) They expend resources on the storage of
information likely to be irrelevant to the study
they are conducting.
(B) They sometimes compromise the accuracy of
their ndings by collecting and analyzing more
information than is strictly required for their trials.
(C) They avoid the risk of overlooking variables that
might affect their ndings, even though doing so
raises their research costs.
(D) Because they attempt to analyze too much
information, they overlook facts that could
emerge as relevant to their studies.
(E) In order to approximate the conditions typical of
medical treatment, they base their methods of
information collection on those used by hospitals.
Supporting ideas
is question asks for an identi cation of speci c
information given in the passage. e passage
describes the proposals of Frazier and Mosteller
as attempting to improve the way clinical trials
have generally been conducted. In describing how
current trials are generally conducted, the passage
states that researchers collect far more background
information on patients than is strictly required for
their trials (lines 4–6) and that they therefore
escalate the costs of the trials.
A Correct. e passage states that researchers
generally collect more information than
they need to perform their clinical trials,
which drives up the costs of the trials.
B e passage makes no judgment about the
accuracy of the information collected by
researchers who currently hold clinical trials.
C e passage states that the risk of
overlooking relevant information in clinical
trials is never entirely eliminable (line 11).
D e passage states that researchers generally
collect more information than is relevant,
not that they overlook relevant information.
E e passage states that, in general,
researchers currently collect more
information than hospitals do (line 6).
e correct answer is A.
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
480
Questions 504–509 refer to the passage on page 408.
504. The primary purpose of the passage is to
(A) assess the validity of a certain view
(B) distinguish between two phenomena
(C) identify the causes of a problem
(D) describe a disturbing trend
(E) allay concern about a particular phenomenon
Main idea
is question requires understanding, in
general terms, the purpose of the passage as a
whole. e rst paragraph identi es an area of
concern: declines in amphibian populations may
constitute a crisis, one that indicates humans’
catastrophic e ects on the environment. e
rest of the passage then goes on to evaluate, as
the second paragraph states, whether claims
of crisis‐level extinctions as a result of human
activity are valid. In making this evaluation,
the passage discusses the possible causes
of extinctions, biologists’ prioritization of
population declines over extinctions, and the
fact that we lack extensive long‐term data on
amphibian populations.
A Correct. e passage’s main purpose is to
assess whether the view that humans are
causing crisis‐level declines in amphibian
populations is valid.
B e passage takes care, particularly in the
third paragraph, to distinguish between
population declines and extinctions, but this
is not its primary purpose.
C e passage makes clear that it is di cult
to identify the real extent of the problem
facing amphibian populations, much less
identify its causes.
D e rst paragraph notes what may seem
to be a disturbing trend—the decline
in amphibian populations—but the rest
of the passage is concerned not with
describing that trend in greater detail, but
rather with determining whether it is in
fact occurring.
E While the passage provides possible
grounds for concluding that concern
about declining amphibian populations is
overblown, it concludes by suggesting that
we might, because we lack data, doom
species and ecosystems to extinction. us,
the overall purpose is not to allay concern.
e correct answer is A.
505. It can be inferred from the passage that the author
believes which of the following to be true of the
environmentalists mentioned in lines 5–6?
(A) They have wrongly chosen to focus on anecdotal
reports rather than on the long‐term data that
are currently available concerning amphibians.
(B) Their recommendations are awed because
their research focuses too narrowly on a single
category of animal species.
(C) Their certainty that population declines in general
are caused by environmental degradation is not
warranted.
(D) They have drawn premature conclusions
concerning a crisis in amphibian populations
from recent reports of declines.
(E) They have overestimated the effects of chance
events on trends in amphibian populations.
Inference
is question asks about the author’s view of
the environmentalists mentioned in the rst
paragraph. ese environmentalists have claimed,
based on amphibian population declines, that
the situation is a crisis and that immediate
action must be taken. e author, however,
states that the declines are only apparently
drastic and questions whether they are real,
thus suggesting that the environmentalists are
drawing conclusions in the absence of a complete
consideration of the situation.
A e passage indicates that anecdotal
reports are insu cient, but so too are other
resources. e fourth paragraph of the
passage makes clear that there is not enough
long‐term data available on which to base
conclusions about amphibian populations.
B e passage does not indicate that the
environmentalists under discussion have
conducted research on any animal species.
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C e passage does not indicate that the
environmentalists in question hold, with
certainty, any particular view regarding
population declines in general.
D Correct. e author argues that the recent
declines may have several di erent causes,
and that environmentalists have jumped to a
conclusion about the cause of the declines as
well as their signi cance.
E e environmentalists, in attributing
population declines to intentional human
activity, have more likely underestimated
than overestimated the e ects of chance
events on amphibian populations.
e correct answer is D.
506. It can be inferred from the passage that the author
believes which of the following to be true of the
amphibian extinctions that have recently been
reported?
(A) They have resulted primarily from human
activities causing environmental degradation.
(B) They could probably have been prevented if
timely action had been taken to protect the
habitats of amphibian species.
(C) They should not come as a surprise, because
amphibian populations generally have been
declining for a number of years.
(D) They have probably been caused by a
combination of chance events.
(E) They do not clearly constitute evidence of
general environmental degradation.
Inference
e author suggests throughout the passage that
recently reported amphibian extinctions may
have several di erent causes: they may be due
to any number of chance events, for example, or
may simply be the result of a small population
that nds itself unable to continue under di cult
conditions, whatever causes those conditions.
A e author states in the second paragraph
that extinctions may occur without a
proximate cause in human activities and
does not make a commitment to any
particular explanation of the amphibian
extinctions.
B at chance events can cause extinctions
suggests that even if habitats had been
protected, extinctions still might have
occurred.
C In the second paragraph, the author says
that extinctions should come as no great
surprise , but this option is imprecise. e
amphibian populations have not generally
been declining for a number of years . e
author says in the third paragraph that
amphibian populations show strong
uctuations; further, in the fourth paragraph,
the author says that there is insu cient
long‐term data to conclude that amphibian
populations have been, or are, in decline.
D e author suggests that the extinctions
may have been caused by chance events, but
there is not enough data to know whether
or not this is probable.
E Correct. e reported extinctions could
have resulted from several di erent causes;
thus, they are not clear evidence of general
environmental degradation.
e correct answer is E.
507. According to the passage, each of the following is true
of endangered amphibian species EXCEPT:
(A) They are among the rarest kinds of amphibians.
(B) They generally have populations that are small in
size.
(C) They are in constant danger of extinction.
(D) Those with decreasing populations are the most
likely candidates for immediate extinction.
(E) They are in danger of extinction due to events
that sometimes have nothing to do with human
activities.
Application
is question asks what the passage does not
say is true of endangered amphibian species. e
second paragraph discusses endangered species,
stating that they are always rare, almost always
small, and, by de nition, under constant threat of
extinction , which may be caused by chance events.
e possibility of their extinction, the passage
states, depends only on the population size, and
not whether that population is increasing or
decreasing.
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
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A e second paragraph mentions rarity as
a characteristic of endangered amphibian
species.
B According to the second paragraph,
endangered amphibian species are generally
those of small populations.
C e second paragraph states that an
endangered population is under constant
threat of extinction.
D Correct. e last sentence of the second
paragraph states that the probability
of extinction due to chance events is
independent of how a population changes
in size. Immediate extinction would more
likely come from such events, whereas
population decline is gradual, even if fairly
rapid.
E Endangered species, according to the
second paragraph, may become extinct due
to chance events—that is, events that have
nothing to do with human activities.
e correct answer is D.
508. Which of the following most accurately describes the
organization of the passage?
(A) A question is raised, a distinction regarding it is
made, and the question is answered.
(B) An interpretation is presented, its soundness is
examined, and a warning is given.
(C) A situation is described, its consequences are
analyzed, and a prediction is made.
(D) Two interpretations of a phenomenon are
described, and one of them is rejected as invalid.
(E) Two methods for analyzing a phenomenon are
compared, and further study of the phenomenon
is recommended.
Evaluation
is question asks about the organization of
the passage as a whole. In the rst paragraph,
the author tells about a situation that has
been interpreted in a particular way by
environmentalists. e passage then proceeds
to consider whether that interpretation is valid,
and while it does not come to a de nitive
conclusion on that point, the nal paragraph
warns about the possible consequences of
not taking the action recommended by the
environmentalists.
A e passage does initially raise a question
regarding whether the environmentalists’
interpretation of events is valid, but it does
not answer that question, for the appropriate
long‐term data are not available.
B Correct. e passage presents
environmentalists’ interpretation of recent
news regarding amphibians, then examines the
soundness of that interpretation. Finally, the
author warns that postponing environmental
action may have disastrous consequences.
C e rst paragraph describes a situation
of possibly drastic declines in amphibian
populations but does not follow this
description with an analysis of its
consequences.
D e passage suggests that apparent declines
in amphibian populations may or may not
constitute a crisis, but it does not reject
either idea.
E While the passage does imply, in its
nal paragraph, that long‐term data on
amphibian populations should be collected,
the passage does not compare two methods
for analyzing amphibian populations or
population declines in those populations.
e correct answer is B.
509. Which of the following best describes the function of
the sentence in lines 35–38?
(A) To give an example of a particular kind of study
(B) To cast doubt on an assertion made in the
previous sentence
(C) To raise an objection to a view presented in the
rst paragraph
(D) To provide support for a view presented in the
rst paragraph
(E) To introduce an idea that will be countered in the
following paragraph
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Evaluation
e sentence in question discusses the way in
which anecdotal reports of population decreases
cannot help biologists determine whether
those decreases are normal uctuations, take
populations to lower levels that are not actually
worrisome, or actually threaten extinctions.
is indicates that the view mentioned in the
rst paragraph—reports of declines indicate a
catastrophic crisis—may be mistaken.
A e sentence does not address a particular
kind of study; it objects to the use of
anecdotal reports in place of actual study.
B e previous sentence describes the
possibilities referred to in the sentence in
question. e sentence does not cast doubt
on any of those possibilities.
C Correct. e view that reports of amphibian
population declines indicate a crisis, as
presented in the rst paragraph, is countered
by the objection here that there are several
possible causes for population declines, and
anecdotal reports cannot distinguish among
those possibilities.
D e rst paragraph is concerned with
articulating the view that amphibian
population declines constitute a crisis.
is sentence does not support that view;
instead, it o ers reason to question it.
E e sentence introduces the idea that
amphibian populations have uctuated
in the past, and the following paragraph
supports this idea by stating that several
amphibian species that appeared almost
extinct in the 1950s and 1960s have
recovered. us, the paragraph does not
counter the sentence.
e correct answer is C.
Questions 510–513 refer to the passage on page 410.
510. The passage mentions which of the following as
a factor that affects the role of P. ochraceus as a
keystone species within different habitats?
(A) The degree to which the habitat is sheltered from
waves
(B) The degree to which other animals within a
habitat prey on mussels
(C) The fact that mussel populations are often not
dominant within some habitats occupied by
P. ochraceus
(D) The size of the P. ochraceus population within
the habitat
(E) The fact that there is great species diversity
within some habitats occupied by P. ochraceus
Supporting idea
is question depends on recognizing what
the passage states about the factors a ecting P.
ochraceus ’s role as a keystone species, which is
di erent in di erent habitats. According to the
passage, P. ochraceus consumes and suppresses
mussel populations in some habitats—speci cally,
those that are wave‐exposed—making it a
keystone predator in those habitats. But in wave‐
sheltered habitats, P. ochraceus does not play the
same role in suppressing mussel populations.
A Correct. e passage clearly states that P.
ochraceus ’s role in wave‐exposed habitats
di ers from its role in wave‐sheltered
habitats.
B e passage says that the impact of P.
ochraceus predation on mussels is not strong
in wave‐sheltered habitats, but this is
not—at least not at all sites—because other
animals are preying on the mussels; rather,
at least at some sites, it is because mussels
are controlled by sand burial.
C e passage does not suggest that mussel
populations are dominant in any habitats
occupied by P. ochraceus .
D e size of the P. ochraceus population a ects
the size of the mussel population within
wave‐exposed habitats, but the passage
does not suggest that P. ochraceus ’s role as a
keystone species depends on the size of its
population within those habitats.
E e only other species the passage mentions
in conjunction with P. ochraceus habitats is
the mussel; the passage does not address
species diversity in these habitats.
e correct answer is A.
7.6 Reading Comprehension Answer Explanations
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GMAT® Offi cial Guide 2018
484
511. Which of the following hypothetical experiments most
clearly exempli es the method of identifying species’
roles that the author considers problematic?
(A) A population of seals in an Arctic habitat is
counted in order to determine whether it is the
dominant species in that ecosystem.
(B) A species of sh that is a keystone species in
one marine ecosystem is introduced into another
marine ecosystem to see whether the species
will come to occupy a keystone role.
(C) In order to determine whether a species of
monkey is a keystone species within a particular
ecosystem, the monkeys are removed from that
ecosystem and the ecosystem is then studied.
(D) Different mountain ecosystems are compared to
determine how geography affects a particular
species’ ability to dominate its ecosystem.
(E) In a grassland experiencing a changing climate,
patterns of species extinction are traced in order
to evaluate the effect of climate changes on
keystone species in that grassland.
Application
Answering this question depends on recognizing
what the author says about identifying species’
roles in habitats and then extending that to
another situation. e author considers a
particular method of studying keystone species
problematic: removing a suspected keystone
species from its habitat and observing what
happens to the ecosystem. e author nds this
problematic because interactions among species
are complex.
A e author does not discuss counting the
members of a population as a problematic
way of determining whether that population
is a dominant species.
B e method that the author nds
problematic has to do with observing
what happens to an ecosystem when a
keystone species is removed from it, not
with observing what happens to a di erent
ecosystem when the species is introduced
into it.
C Correct. e author states explicitly that
removing a species from a habitat in
order to determine its keystone status is
problematic. Removing the monkeys from
their habitat is a clear example of this
problematic practice.
D Comparison of habitats in order to
determine geography’s e ect on a
particular species’ dominance would most
likely nd favor with the author, for this is
the approach the author seems to advocate
in investigating P. ochraceus ’s keystone
status.
E e author does not discuss tracing patterns
of extinction or changing climates in the
passage.
e correct answer is C.
512. Which of the following, if true, would most clearly
support the argument about keystone status advanced
in the last sentence of the passage (lines 24–31)?
(A) A species of bat is primarily responsible for
keeping insect populations within an ecosystem
low, and the size of the insect population in turn
affects bird species within that ecosystem.
(B) A species of iguana occupies a keystone role
on certain tropical islands, but does not play
that role on adjacent tropical islands that are
inhabited by a greater number of animal species.
(C) Close observation of a savannah ecosystem
reveals that more species occupy keystone
roles within that ecosystem than biologists had
previously believed.
(D) As a keystone species of bee becomes more
abundant, it has a larger effect on the ecosystem
it inhabits.
(E) A species of moth that occupies a keystone role
in a prairie habitat develops coloration patterns
that camou age it from potential predators.
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Evaluation
To answer this question, focus on the argument
advanced in the last sentence of the passage and
identify what information would support that
argument. In the last sentence of the passage, the
author claims that keystone status depends on
context. e author then o ers three contextual
factors that may a ect a species’ keystone status:
geography, community diversity (i.e., the number
of species in a given habitat), and length of
species interaction. Evidence supporting this
argument would show that context is important
to a species’ keystone status.
A is scenario does not indicate anything
about keystone status; this is simply a
description of how species populations in a
single ecosystem a ect one another.
B Correct. at the iguana is a keystone
species in a location that has limited species
diversity but not a keystone species in a
location that has greater species diversity
suggests that keystone status does indeed
depend on context. us, this example
supports the author’s argument in the last
sentence of the passage.
C at biologists were mistaken about
keystone species in a particular ecosystem
does not have a bearing on whether
keystone status is context dependent.
D It is not surprising that an increase
in a species’ population would lead to
that species having a larger e ect on its
ecosystem—but this does not speak directly
to the question of whether keystone status
itself depends on context.
E A keystone species enhancing its ability to
survive in a single ecosystem does not lend
any support to the idea that keystone status
depends on context. e moth’s keystone
status would have to undergo some change
for this to have a bearing on the question of
context.
e correct answer is B.
513. The passage suggests which of the following about the
identi cation of a species as a keystone species?
(A) Such an identi cation depends primarily on the
species’ relationship to the dominant species.
(B) Such an identi cation can best be made
by removing the species from a particular
ecosystem and observing changes that occur in
the ecosystem.
(C) Such an identi cation is likely to be less reliable
as an ecosystem becomes less diverse.
(D) Such an identi cation seems to depend on
various factors within the ecosystem.
(E) Such an identi cation can best be made by
observing predation behavior.
Inference
Answering this question requires identifying how
the passage suggests that keystone species should
be identi ed. e passage identi es a particular
way in which keystone status should not be
determined: removing a species and observing
what happens to the ecosystem. e passage also
argues that keystone status depends strongly on
context: that is, an ecosystem’s characteristics,
including its geography and inhabitants,
determine its keystone species.
A While the passage uses an example of a
keystone species, P. ochraceus , which preys on
a species that would, in the keystone species’
absence, be dominant, there is nothing to
suggest that a keystone species must have a
particular relationship with the dominant,
or potentially dominant, species in an
ecosystem.
B e passage explicitly states that this
method of identi cation would be
problematic.
C A reduction in an ecosystem’s diversity
might alter which species occupy keystone
roles in that ecosystem, the passage suggests,
but there is no indication that identifying
such species would become more di cult.
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D Correct. If, as the passage suggests,
keystone status for any given species
depends on the context of the ecosystem
in which it lives, then it is likely that
identifying keystone species depends
strongly on understanding what factors
of the ecosystem contribute to creating
keystone status. e passage lists such
factors as geography, community diversity,
and species interaction.
E While the passage uses a predator,
P.ochraceus , as its example of a keystone
species, there is no indication that predation
is an essential component of the actual
de nition of keystone species ( one whose
e ects are much larger than would be predicted
from its abundance ).
e correct answer is D.
Questions 514–516 refer to the passage on page 412 .
514. According to the passage, the anatomical evidence
provided by the preserved soft bodies of conodonts
led scientists to conclude that
(A) conodonts had actually been invertebrate
carnivores
(B) conodonts’ teeth were adapted from protective
bony scales
(C) conodonts were primitive vertebrate suspension
feeders
(D) primitive vertebrates with teeth appeared earlier
than armored vertebrates
(E) scientists’ original observations concerning
the phosphatic remains of conodonts were
essentially correct
Supporting ideas
is question depends on understanding how
a particular type of evidence—the preserved
soft bodies of conodonts—supports a particular
conclusion stated in the passage. e third
paragraph makes this relationship explicit,
explaining that certain features of conodonts
show them to be more primitive than other
vertebrates. Further, those features indicate
that they came before ostracoderms and other
armored jawless shes. ese remains support
the conclusion stated in the second paragraph
regarding teeth being more primitive than
external armor.
A e passage states explicitly that conodonts
were not invertebrates but rather vertebrates .
B is view is attributed to certain
traditionalists but is contradicted by other
paleontological evidence presented in the
second and third paragraphs. According to
the third paragraph, the evidence provided
by the preserved soft bodies of conodonts
undermines this traditional view.
C e nal sentence of the passage indicates
that the evidence in question supports the
conclusion that conodonts were predators
rather than suspension feeders.
D Correct. e third paragraph explains how
conodonts’ remains support the conclusion
that teeth were more primitive than external
armor.
E e second paragraph explains that
originally, scientists thought that early
vertebrates were not predators—but the
remainder of the passage indicates that
this idea is inconsistent with more recent
evidence described in the passage.
e correct answer is D.
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515. The second paragraph in the passage serves primarily
to
(A) outline the signi cance of the 1981 discovery of
conodont remains to the debate concerning the
development of the vertebrate skeleton
(B) contrast the traditional view of the development
of the vertebrate skeleton with a view derived
from the 1981 discovery of conodont remains
(C) contrast the characteristics of the ostracoderms
with the characteristics of earlier soft-bodied
vertebrates
(D) explain the importance of the development of
teeth among the earliest vertebrate predators
(E) present the two sides of the debate concerning
the development of the vertebrate skeleton
Evaluation
is question depends on understanding the
second paragraph in the context of the passage as
a whole. e second paragraph begins by noting
the traditional view of the vertebrate skeleton—
that it was a defense against predators—and then
goes on to explain that other paleontologists
argued against this idea, claiming instead that
vertebrates began as predators and that teeth were
a more primary feature than external armor.
A e second paragraph focuses on describing
the debate rather than on the distinctive
contribution of the 1981 discovery to that
debate.
B e second paragraph does not explicitly
indicate whether the opposition to the
traditional view originally rested on the
1981 discovery of conodont remains. In fact,
the surrounding discussion, in the rst and
third paragraphs, suggests that the discovery
in 1981 turned out to support the opposing
view, which some paleontologists already
held at that time.
C e mention of ostracoderms in the second
paragraph merely serves to indicate how
the traditionalists’ arguments might have
seemed plausible. e paragraph as a
whole is not devoted to contrasting the
ostracoderms with earlier soft-bodied
vertebrates.
D e development of teeth gures in the
second paragraph, but this development
is mentioned rst as a feature that some
believed to have been adapted from
protective scales; only the nal sentence
of the paragraph connects teeth to early
vertebrate predators.
E Correct. According to the passage, the
debate concerning the development of
the vertebrate skeleton hinges on whether
vertebrates began as predators, with teeth,
or whether skeletal defenses such as external
armor evolved rst. e primary purpose of
the second paragraph is to distinguish these
two sides.
e correct answer is E.
516. It can be inferred that on the basis of the 1981
discovery of conodont remains, paleontologists could
draw which of the following conclusions?
(A) The earliest vertebrates were sedentary
suspension feeders.
(B) Ostracoderms were not the earliest vertebrates.
(C) Defensive armor preceded jaws among
vertebrates.
(D) Paired eyes and adaptations for activity are
de nitive characteristics of vertebrates.
(E) Conodonts were unlikely to have been predators.
Inference
What could paleontologists conclude, based on
the 1981 discovery of conodont remains? at
discovery, according to the passage, supported the
view of certain paleontologists that the earliest
vertebrates were predators with teeth—unlike the
ostracoderms, which had no jaws.
A According to the second paragraph,
traditionalists believed that early vertebrates
were sedentary suspension feeders. But
the 1981discovery supported instead the
hypothesis that early vertebrates were
predators instead.
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B Correct. According to the third paragraph,
the conodonts’ body structures indicated
that they were more primitive than the
ostracoderms, so the ostracoderms must not
have been the earliest vertebrates.
C Traditionalists argued that teeth were
adapted from bony scales that provided
defensive armor, but the 1981discovery
suggested that teeth preceded such scales.
D Paleontologists knew prior to the
1981discovery that paired eyes and other
adaptations are characteristics of vertebrates.
ey used this knowledge to help them
interpret the 1981discovery.
E e third paragraph indicates that
conodonts, given their teeth, were most
likely predators.
e correct answer is B.
Questions 517–528 refer to the passage on page 414.
517. The primary purpose of the passage is to
(A) advocate a more positive attitude toward
technological change
(B) discuss the implications for employees of the
modernization of a telephone exchange
(C) consider a successful challenge to the
constructivist view of technological change
(D) challenge the position of advocates of
technological determinism
(E) suggest that the social causes of technological
change should be studied in real situations
Main idea
is question asks for an assessment of what
the passage as a whole is doing. e passage
introduces Clark’s study as a solid contribution
(line 3) to the debate between technological
determinists and social constructivists. In the
second paragraph, Braverman is introduced as
holding a position of social constructivism, a
position that Clark takes issue with. In the nal
paragraph, the passage holds that Clark refutes the
extremes of the constructivists (line 31), and Clark’s
arguments challenging social constructivism are
then described.
A e passage takes no position on the merits
of technological change but is concerned
only with the role of such change in society.
B e passage mentions telephone exchange
workers as an example that helps
illustrate the more central debate between
determinists and constructivists.
C Correct. e passage is mainly concerned
with portraying Clark’s view as a successful
challenge to constructivism.
D e passage describes Clark’s view as a
successful challenge to social constructivism,
not technological determinism.
E e passage is concerned with describing
a challenge to social constructivism and
not with suggesting the context in which
technological change ought to be studied.
e correct answer is C.
518. Which of the following statements about the
modernization of the telephone exchange is supported
by information in the passage?
(A) The new technology reduced the role of
managers in labor negotiations.
(B) The modernization was implemented without the
consent of the employees directly affected by it.
(C) The modernization had an impact that went
signi cantly beyond maintenance routines.
(D) Some of the maintenance workers felt victimized
by the new technology.
(E) The modernization gave credence to the view of
advocates of social constructivism.
Supporting ideas
is question requires recognizing information
contained in the passage. e passage states in
the rst paragraph that Clark’s study focused
on the modernization of a telephone exchange
and the e ect this had on maintenance work
and workers. After describing Braverman’s
analysis in the second paragraph as being at
odds with Clark’s views, the passage discusses
Clark’s views in more detail in the nal
paragraph. As part of this discussion, the
passage notes that Clark shows how a change
from maintenance‐intensive electromechanical
switches to semielectronic switching systems at
the telephone exchange altered work tasks,
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skills, training opportunities, administration, and
organization of workers (lines 42–44). us, the
passage shows that the modernization of the
telephone exchange a ected much more than
maintenance routines.
A e passage does not discuss whether new
technology reduces the role of managers in
labor negotiations.
B e passage does not discuss the role of
employee consent in the modernization of
the telephone exchange.
C Correct. e passage states that the
modernization of the telephone exchange
a ected tasks, skills, training, administration,
and the organization of workers.
D e passage does not suggest that
maintenance workers felt victimized
by the modernization of the telephone
exchange.
E e passage describes modernization
as a fact viewable from a perspective of
social constructivism or technological
determinism, but that does not in itself
support either view.
e correct answer is C.
519. Which of the following most accurately describes
Clark’s opinion of Braverman’s position?
(A) He respects its wide‐ranging popularity.
(B) He disapproves of its misplaced emphasis on the
in uence of managers.
(C) He admires the consideration it gives to the
attitudes of the workers affected.
(D) He is concerned about its potential to impede
the implementation of new technologies.
(E) He is sympathetic to its concern about the
impact of modern technology on workers.
Inference
Answering this question requires inferring
what the passage’s author likely believes. e
passage describes Braverman’s position as one
of mainstream social constructivism (lines
23–24), a position that Clark takes issue with.
Although it describes Braverman’s position, the
rest of the passage is devoted to showing how
Clark’s position takes issue with Braverman’s.
In the second paragraph, the passage describes
Clark as holding that technology can be a primary
determinant of social and managerial organization
(lines 9–11), which suggests that managers are
sometimes subordinate to technological change.
In lines 15–17, however, Braverman is described
as holding that the shape of a technological system is
subordinate to the manager’s desire to wrest control of
the labor process from the workers , which shows that
Clark and Braverman are at odds on this point.
A Since the passage says that Clark believes
an important insight has been obscured by the
recent sociological fashion that Braverman’s
views exemplify (lines 11–14), one cannot
infer that Clark respects the popularity of
Braverman’s views.
B Correct. e passage shows that Clark
believes managers to have less in uence over
how technology a ects an organization than
Braverman claims that they have.
C e passage does not indicate that Clark
admires any aspect of Braverman’s position.
D e passage does not indicate that Clark
considers impediments to modernization.
E e passage does not indicate that Clark is
sympathetic to any concerns attributed to
Braverman.
e correct answer is B.
520. The information in the passage suggests that which of
the following statements from hypothetical sociological
studies of change in industry most clearly exempli es
the social constructivists’ version of technological
determinism?
(A) It is the available technology that determines
workers’ skills, rather than workers’ skills
in uencing the application of technology.
(B) All progress in industrial technology grows out of
a continuing negotiation between technological
possibility and human need.
(C) Some organizational change is caused by
people; some is caused by computer chips.
(D) Most major technological advances in industry
have been generated through research and
development.
(E) Some industrial technology eliminates jobs, but
educated workers can create whole new skills
areas by the adaptation of the technology.
7.6 Reading Comprehension Answer Explanations
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Application
is question requires understanding di erent
points of view discussed in the passage. In
the rst paragraph, the passage mentions the
debate involving technological determinism
and social constructivism. In the second and
third paragraphs, the passage uses Braverman’s
analysis to illustrate the social constructivists’
position and in the third paragraph suggests
that the constructivists are misrepresenting
technological determinism (line 24). In lines 29–30,
the constructivists are reported to hold that
technological determinism views technology as
existing outside society, capable of directly in uencing
skills and work organization.
A Correct. is statement is consistent with
the constructivists’ view that technological
determinism sees technology as outside of
society, in uencing workers’ skills.
B e passage states that the constructivists
hold that technological determinists are
supposed to believe . . . that machinery imposes
appropriate forms of order on society (lines
25–27), suggesting that no negotiation is
present.
C According to the description of them in the
passage, constructivists portray technological
determinists as believing that technology,
not people, drives organizational change.
D e passage does not portray either
constructivists or determinists as being
concerned with technological research and
development.
E e passage does not portray either
constructivists or determinists as being
concerned with technology‐driven job
elimination or creation.
e correct answer is A.
521. The information in the passage suggests that Clark
believes that which of the following would be true
if social constructivism had not gained widespread
acceptance?
(A) Businesses would be more likely to modernize
without considering the social consequences of
their actions.
(B) There would be greater understanding of the role
played by technology in producing social change.
(C) Businesses would be less likely to understand
the attitudes of employees affected by
modernization.
(D) Modernization would have occurred at a slower
rate.
(E) Technology would have played a greater part in
determining the role of business in society.
Inference
Answering this question involves
understanding a point of view as it is described
in the passage. e passage aligns Clark’s study
closely with the technological determinists,
summarizing his view in lines 9–11: technology
can be a primary determinant of social and
managerial organization . In the following
sentence, the passage states that Clark believes
that this possibility is obscured by the recent
sociological fashion, exemplified by Braverman’s
analysis (lines 11–13). After illustrating
Braverman’s analysis, the passage then states
that it represents social constructivism .
A According to the passage, Clark holds that
constructivists obscure how modernization
might have social consequences.
B Correct. According to the passage, Clark
sees constructivism as obscuring the
possibility that technology plays a primary
role in social change.
C e passage does not discuss how the
attitudes of employees are perceived by their
employers.
D e passage describes a debate about the
history and sociology of technology; it does
not suggest that sociological analyses a ect
the pace of modernization.
E e passage describes a debate about the
history and sociology of technology; it
does not suggest that sociological analyses
a ect the role that technology plays in
business.
e correct answer is B.
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522. According to the passage, constructivists employed
which of the following to promote their argument?
(A) Empirical studies of business situations involving
technological change
(B) Citation of managers supportive of their position
(C) Construction of hypothetical situations that
support their view
(D) Contrasts of their view with a misstatement of an
opposing view
(E) Descriptions of the breadth of impact of
technological change
Supporting ideas
Answering this question involves recognizing
information given in the passage. e passage
indicates that a debate exists between
technological determinists and social
constructivists, suggesting that these views are
in opposition. e passage goes on to state that
constructivists gain acceptance by misrepresenting
technological determinism (lines 23–24). is
misrepresentation is presented as the alternative
to constructivism (lines 27–28), suggesting
that constructivists promoted their own view
by contrasting it with a misrepresentation of
determinists’ views.
A e passage mentions empirical studies in
relation to Clark’s study but not Braverman’s
analysis.
B e passage does not mention that
managers were supportive of any particular
point of view within the sociology of
technology.
C e passage does not mention any
hypothetical situations as being used by the
constructivists in support of their view.
D Correct. e passage indicates that the
constructivists have come into fashion
by contrasting their own views with
a misrepresentation of the views of
technological determinists.
E e passage does not describe the
constructivists as making determinations
regarding the degree of impact that
technological change has on social or
managerial organization.
e correct answer is D.
523. The author of the passage uses the expression “are
supposed to” in line 25 primarily in order to
(A) suggest that a contention made by
constructivists regarding determinists is
inaccurate
(B) de ne the generally accepted position of
determinists regarding the implementation of
technology
(C) engage in speculation about the motivation of
determinists
(D) lend support to a comment critical of the
position of determinists
(E) contrast the historical position of determinists
with their position regarding the exchange
modernization
Evaluation
is question requires understanding how a
particular phrase functions in the passage as
a whole. In the third paragraph the passage
states that constructivists gain acceptance by
misrepresenting technological determinism
(lines 23–24) and follows this claim with an
example of this misrepresentation, stating that
technological determinists are supposed to believe,
for example (lines 25–26). is line implies that
the constructivist view of the determinists is
inaccurate.
A Correct. e passage uses the expression
in part to provide an example of the
constructivists’ misrepresentation of the
determinists.
B e passage indicates that the view
attributed to the determinists is a
misrepresentation, not one that is generally
accepted by determinists.
C e expression in the passage is part
of a discussion about the motivation of
constructivists, not determinists.
D e expression in the passage is part
of a discussion that is critical of the
constructivists, not the determinists.
E e passage does not describe either the
historical position of determinists or their
position on the exchange modernization.
e correct answer is A.
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524. Which of the following statements about Clark’s study
of the telephone exchange can be inferred from
information in the passage?
(A) Clark’s reason for undertaking the study was to
undermine Braverman’s analysis of the function
of technology.
(B) Clark’s study suggests that the implementation
of technology should be discussed in the context
of con ict between labor and management.
(C) Clark examined the impact of changes in the
technology of switching at the exchange in terms
of overall operations and organization.
(D) Clark concluded that the implementation of new
switching technology was equally bene cial to
management and labor.
(E) Clark’s analysis of the change in switching
systems applies only narrowly to the situation at
the particular exchange that he studied.
Inference
is question requires understanding what
the passage implies in its discussion of a
point of view. e details of Clark’s views are
discussed primarily in the nal paragraph. e
passage states that on an empirical level, Clark
demonstrates that technological change regarding
switches at the telephone exchange altered work
tasks, skills, training opportunities, administration,
and organization of workers (lines 42–44). e
passage goes on to state Clark’s contention that
these changes even in uenced negotiations
between management and labor unions.
A e passage indicates that Clark’s
study addressed the extremes of both
technological determinism and social
constructivism. It cites Braverman as a
proponent of social constructivism but
provides no evidence that Clark’s motivation
in beginning his study was speci cally to
target an analysis o ered by Braverman.
B e passage indicates that Clark attributed
some organizational change to the way
labor and management negotiated the
introduction of technology but does not
mention con ict between them.
C Correct. According to the passage, Clark
concludes that changes to the technology of
switches had an in uence on several aspects
of the overall operations and organization of
the telephone exchange.
D e passage does not indicate that Clark
assesses the bene ts of technological change
to either labor or management.
E e passage indicates that Clark believes the
change in switching technology in uenced
many aspects of the overall operations of the
telephone exchange.
e correct answer is C.
Questions 525–529 refer to the passage on page 416.
525. The passage implies that which of the following was
a reason that the proportion of verdicts in favor of
patentees began to increase in the 1830s ?
(A) Patent applications approved after 1836 were
more likely to adhere closely to patent law.
(B) Patent laws enacted during the 1830s better
de ned patent rights.
(C) Judges became less prejudiced against
patentees during the 1830s.
(D) After 1836, litigated cases became less
representative of the population of patent
disputes.
(E) The proportion of patent disputes brought to trial
began to increase after 1836.
Inference
e question asks which statement can be
reasonably inferred, from information provided
in the passage, to be a reason for the increase in
proportion of verdicts favoring patentees, starting
in the 1830s. e second paragraph argues that
what changed in that decade was not judges’
attitudes toward patent law, but the types of
patent cases that were litigated. It explains that
a law passed in 1836 required that, for the rst
time in U.S. history, applications for patents had
to be examined for their adherence to patent law
before a patent would be issued. is information
implies that patents granted after 1836 were more
likely to adhere to patent law and were thus more
likely to be upheld in court.
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A Correct . e passage implies that patents
granted after the 1836 law went into e ect
were more likely to adhere to patent law.
B e passage does not indicate that any law
mentioned made changes to the de nition
of patent rights; rather, the passage indicates
that the patent system was revised to require
that patent applications be reviewed for
adherence to existing law.
C e passage rejects the explanation that
judges’ attitudes toward patent rights
became more favorable.
D e passage indicates that the population
of disputes that were litigated changed
after 1836, but it does not suggest that the
population of litigated disputes di ered
from that of patent disputes as a whole.
E e passage does not indicate any change in
the proportion of patent disputes brought to
trial.
e correct answer is A.
526. The passage implies that the scholars mentioned in
line 8 would agree with which of the following criticisms
of the American patent system before 1830?
(A) Its de nition of property rights relating to
inventions was too vague to be useful.
(B) Its criteria for the granting of patents were not
clear.
(C) It made it excessively dif cult for inventors to
receive patents.
(D) It led to excessive numbers of patent‐
infringement suits.
(E) It failed to encourage national economic growth.
Inference
is question asks about a statement implied
by the passage. e scholars mentioned in line 8
question whether U.S. patent law achieved its
goal. at goal is described in the rst sentence
of the passage: to encourage America’s economic
growth. us, it is reasonable to conclude that
the scholars would criticize the pre‐1830 patent
system for failing to encourage economic growth.
A e scholars contend that judges rejected
patents for arbitrary reasons, not because the
de nition of property rights was vague.
B e passage does not indicate that the
scholars were critical of the criteria for
granting patents.
C e scholars are concerned with inventors’
attempts to protect their patents, not the
di culty of acquiring a patent in the rst
place.
D e passage does not imply that the scholars
in question believed that too many patent‐
infringement suits were brought to court,
but rather that too few succeeded.
E Correct. e scholars doubt that patent
law helped to achieve its goal, which was to
encourage economic growth.
e correct answer is E.
527. It can be inferred from the passage that the frequency
with which pre‐1830 cases have been cited in court
decisions is an indication that
(A) judicial support for patent rights was strongest in
the period before 1830
(B) judicial support for patent rights did not increase
after 1830
(C) courts have returned to judicial standards that
prevailed before 1830
(D) verdicts favoring patentees in patent‐infringement
suits did not increase after 1830
(E) judicial bias against patentees persisted after
1830
Inference
e question asks what is indicated by the
frequency with which pre‐1830 cases have been
cited in court decisions. e second paragraph
rejects some scholars’ claims that judges prior to
the 1830s were antipatent , while judges after that
time were more accepting of patent rights. e
passage supports its critique by pointing out that
decisions made by judges before the 1830s have
been cited as precedents by later judges just as
frequently as post‐1830s decisions have been. is
implies that later judges’ attitudes toward patent
rights were similar to those of pre‐1830s judges.
us, there is no reason to believe judges’ attitudes
toward patent rights changed at that time.
7.6 Reading Comprehension Answer Explanations
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A e passage argues that judicial support for
patents did not change in the 1830s.
B Correct . Pre‐1830s court decisions have
been cited as frequently as later decisions,
suggesting no change in judges’ attitudes.
C e passage does not indicate that judicial
standards changed from, and then returned
to, those that prevailed before 1830.
D Although actual numbers of favorable
verdicts are not mentioned, the passage
indicates that the proportion of verdicts
decided in favor of patentees did, in fact,
increase beginning in the 1830s.
E e passage rejects the notion that judges
were biased against patentees either before
or after 1830.
e correct answer is B.
528. It can be inferred from the passage that the author
and the scholars referred to in line 21 disagree about
which of the following aspects of the patents defended
in patent‐infringement suits before 1830?
(A) Whether the patents were granted for inventions
that were genuinely useful
(B) Whether the patents were actually relevant to the
growth of the United States economy
(C) Whether the patents were particularly likely to be
annulled by judges
(D) Whether the patents were routinely invalidated
for reasons that were arbitrary
(E) Whether the patents were vindicated at a
signi cantly lower rate than patents in later suits
Inference
e question depends on recognizing di erences
between two explanations—one favored by the
scholars mentioned in line 21 , the other favored by
the author—for the frequency with which patents
were invalidated in U.S. courts prior to 1830. e
rst paragraph describes the scholars’ view that
judges before 1830 were antipatent and rejected
patentees’ claims for arbitrary reasons . e author
of the passage rejects that view. As an alternate
explanation, the author in the second paragraph
implies that earlier patents often violated copyright
law; this view is supported with reference to an
1836 revision to the patent system which instituted
a procedure by which patent applications were
inspected to ensure adherence to patent law.
A e author and the scholars are both
focused on protecting inventors’ property
rights, not with their inventions’ utility.
B Although the passage suggests that the
scholars thought America’s patent system did
not help encourage economic growth, there
is no suggestion that either the scholars or
the author believes actual patents defended in
court were irrelevant to economic growth.
C Both the scholars and the author believe
that patents defended in court prior to 1830
were more likely to be invalidated than were
patents in later legal disputes.
D Correct. e scholars claim that judges
before 1830 decided against patentees for
arbitrary reasons, but the passage suggests
that the patents may have been invalidated
because they failed to adhere to patent law.
E Both the scholars and the author accept
that patents were upheld in court less often
before 1830 than after.
e correct answer is D.
529. The author of the passage cites which of the following
as evidence challenging the argument referred to in
lines 14–15 ?
(A) The proportion of cases that were decided
against patentees in the 1820s
(B) The total number of patent disputes that were
litigated from 1794 to 1830
(C) The fact that later courts drew upon the legal
precedents set in pre‐1830 patent cases
(D) The fact that the proportion of judicial decisions
in favor of patentees began to increase during
the 1830s
(E) The constitutional rationale for the 1836 revision
of the patent system
Supporting idea
e question asks what evidence the author
brings to bear against the argument referred to
in lines 14–15. In the rst paragraph, the author
summarizes scholars’ arguments to the conclusion
that judges’ attitudes toward patent rights shifted
in the 1830s, based on the fact that judges
earlier had routinely ruled against patentees in
lawsuits whereas judges after that time provided
more protection for patent rights. In the second
paragraph the author challenges the claim that
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495
judges’ attitudes shifted. e author provides
evidence that judges after the 1830s cited legal
precedents set in pre‐1830s cases, suggesting that
their views had not changed.
A e proportion of cases decided against
patentees in the 1920s is cited as evidence
that supports the scholars’ argument in the
rst paragraph, not as evidence challenging
their views.
B e total number of disputes litigated is not
mentioned in the passage.
C Correct. e fact that judges after 1830
cited earlier cases as precedents is used as
evidence to challenge scholars’ claims that
judges’ attitudes shifted around 1830.
D e change in the proportion of decisions
in favor of patentees is a fact that both
the scholars and the author of the passage
attempt to explain.
E No constitutional rationale for the 1836 law
is mentioned in the passage.
e correct answer is C.
Questions 530–536 refer to the passage on page 418.
530. The author of the passage discusses Krontiris primarily
to provide an example of a writer who
(A) is highly critical of the writings of certain
Renaissance women
(B) supports Kelly’s view of women’s status during
the Renaissance
(C) has misinterpreted the works of certain
Renaissance women
(D) has rejected the views of both Burckhardt and Kelly
(E) has studied Renaissance women in a wide variety
of social and religious contexts
Evaluation
is question focuses on the author’s reason
for mentioning Krontiris’s work. e passage
states that Krontiris, in her discussion of six
Renaissance women writers, is an example of
scholars who are optimistic about women’s
achievements but also suggest that these women
faced signi cant obstacles. She is a writer who, in
other words, agrees with neither Kelly’s negative
views nor Burckhardt’s positive approach.
A e passage indicates that Krontiris uses
the Renaissance women writers’ works as
historical evidence, not that she o ered any
criticism of the works themselves.
B Krontiris’s work, according to the author,
is cautiously optimistic about women’s
achievements during the Renaissance. is
contradicts Kelly’s view that the status of
women declined during this time.
C e author suggests that Krontiris may
have erred in taking her six subjects as
representative of all women during the
Renaissance, not that she made any
misinterpretations of their actual writing.
D Correct. e author uses Krontiris as an
example of those feminist scholars who have
rejected the overgeneralized approaches of
both Kelly and Burckhardt.
E e author makes clear that Krontiris’s
study focuses on literate Renaissance
women, who constituted a small minority.
e correct answer is D.
531. According to the passage, Krontiris’s work differs from
that of the scholars mentioned in line 12 in which of
the following ways?
(A) Krontiris’s work stresses the achievements of
Renaissance women rather than the obstacles to
their success.
(B) Krontiris’s work is based on a reinterpretation of
the work of earlier scholars.
(C) Krontiris’s views are at odds with those of both
Kelly and Burkhardt.
(D) Krontiris’s work focuses on the place of women
in Renaissance society.
(E) Krontiris’s views are based exclusively on the
study of a privileged group of women.
Supporting idea
is question asks what the passage directly states
about the di erence between Krontiris’s work
and the feminist scholars mentioned in the rst
paragraph. e feminist scholars mentioned in
the rst paragraph explore di erences among
Renaissance women, particularly their social status
and religion, and thus complicate Burckhardt’s and
Kelly’s generalizations. Krontiris’s work, on the other
hand, focuses on Renaissance women writers, who
are a distinctly privileged and small social group.
7.6 Reading Comprehension Answer Explanations
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A e second paragraph makes clear that
Krontiris addresses the obstacles faced by
Renaissance women.
B e passage does not suggest that
Krontiris is reinterpreting or drawing on
reinterpretations of the work of earlier
scholars.
C e second paragraph shows that Krontiris’s
work does complicate both Burckhardt’s and
Kelly’s views, but in this, she is in agreement
with the feminist scholars mentioned in the
rst paragraph.
D Both Krontiris and the feminist scholars
mentioned in the rst paragraph are
concerned with the place of women in
Renaissance society.
E Correct. e feminist scholars mentioned
in the rst paragraph are concerned with
women of di erent social classes and
religions, whereas Krontiris’s work focuses
on a limited social group.
e correct answer is E.
532. According to the passage, feminist scholars cite
Burckhardt’s view of Renaissance women primarily for
which of the following reasons?
(A) Burckhardt’s view forms the basis for most
arguments refuting Kelly’s point of view.
(B) Burckhardt’s view has been discredited by Kelly.
(C) Burckhardt’s view is one that many feminist
scholars wish to refute.
(D) Burckhardt’s work provides rich historical
evidence of inequality between Renaissance
women and men.
(E) Burckhardt’s work includes historical research
supporting the arguments of the feminist
scholars.
Supporting idea
is question asks what the passage says
explicitly about why feminist scholars reference
Burckhardt’s view of Renaissance women. e
rst paragraph states that Burckhardt’s view is
that Renaissance women enjoyed perfect equality
with men, and then follows that by noting how
feminist scholars have repeatedly cited this view
to contrast it with extensive evidence of women’s
inequality during the Renaissance.
A e passage does not indicate that any
feminist scholars cite Burckhardt to refute
Kelly’s view. It uses Krontiris as an example
of scholars who refute Kelly’s point of view
to a certain degree, but Krontiris does not
use Burckhardt’s view as her basis for doing
so; Krontiris argues against Burckhardt as
well.
B According to the rst paragraph, Kelly’s
work was in certain ways inconsistent
with Burckhardt’s view, but that is not a
reason why Burckhardt’s view is cited by
feminist scholars. Rather, according to
the passage, they cite it in order to argue
against it.
C Correct. Many feminist scholars wish to
refute Burckhardt’s view that Renaissance
women and men were equal.
D As the rst paragraph makes clear,
Burckhardt’s work emphasizes equality, not
inequality, between Renaissance women and
men.
E e passage does not discuss the historical
research on which Burckhardt based his
work.
e correct answer is C.
533. It can be inferred that both Burckhardt and Kelly have
been criticized by the scholars mentioned in line 12 for
which of the following?
(A) Assuming that women writers of the Renaissance
are representative of Renaissance women in
general
(B) Drawing conclusions that are based on the study
of an atypical group of women
(C) Failing to describe clearly the relationship
between social status and literacy among
Renaissance women
(D) Failing to acknowledge the role played by
Renaissance women in opposing cultural
stereotypes
(E) Failing to acknowledge the ways in which
social status affected the creative activities of
Renaissance women
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Inference
Line 12 refers to feminist scholars who have
rejected both Kelly’s and Burckhardt’s views
of the status of Renaissance women. e next
sentence states that the feminist scholars use
class and religious di erences among Renaissance
women to argue against Kelly’s and Burckhardt’s
generalizations, which were based on upper‐class
Italian women.
A e second paragraph suggests that
Krontiris at times con ates Renaissance
women writers and women in general,
but the passage does not indicate that the
feminist scholars believe this of Kelly or
Burckhardt.
B Correct. e feminist scholars mentioned
study di erent types of Renaissance women
and so reject Kelly’s and Burckhardt’s
conclusions that were based on a group that
was not in fact typical.
C Krontiris, not Kelly and Burckhardt, is the
scholar who, according to the passage, fails
to address the relationship between literacy
and social status.
D e passage provides no grounds for
determining whether Kelly, Burckhardt,
or the feminist scholars mentioned in the
rst paragraph dealt with Renaissance
women’s opposition to cultural stereotypes;
Krontiris’s work is concerned with this
question.
E e rst paragraph suggests that feminist
scholars criticized Kelly and Burckhardt for
failing to acknowledge the ways in which
social status complicates any generalizations
that can be made about Renaissance
women’s lives, not their creative activities
speci cally.
e correct answer is B.
534. The author of the passage suggests that Krontiris
incorrectly assumes that
(A) social differences among Renaissance women
are less important than the fact that they were
women
(B) literacy among Renaissance women was more
prevalent than most scholars today acknowledge
(C) during the Renaissance, women were able to
successfully oppose cultural stereotypes relating
to gender
(D) Renaissance women did not face many dif cult
social obstacles relating to their gender
(E) in order to attain power, Renaissance women
attacked basic assumptions in the ideologies
that oppressed them
Inference
e rst statement the author makes about
Krontiris, in the second paragraph, concerns
what the author characterizes as a problem with
Krontiris’s work. Krontiris takes the Renaissance
women writers she studies as representative of
all Renaissance women; the author says that
designating women as the most important
grouping fails to consider whether other social
di erences might make for di erences in
experience.
A Correct. e author indicates that
Krontiris’s error lies in assuming that
women’s identity as women trumps social
and other di erences.
B e author does not suggest that Krontiris
assumes inappropriate literacy levels
among Renaissance women, but rather
that Krontiris does not give su cient
consideration to the idea that women who
could read and write most likely led lives
very di erent from those of women who
could not read and write.
C e author says that Krontiris suggests that
there were many cultural stereotypes that
women were not able to oppose e ectively.
D Krontiris, according to the author,
acknowledges the many social obstacles
faced by women on the basis of their gender.
E According to the author, Krontiris’s
concluding remarks suggest that
Renaissance women seldom attacked the basic
assumptions in the ideologies that oppressed
them.
e correct answer is A.
7.6 Reading Comprehension Answer Explanations
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535. The last sentence in the passage serves primarily to
(A) suggest that Krontiris’s work is not
representative of recent trends among feminist
scholars
(B) undermine the argument that literate women
of the Renaissance sought to oppose social
constraints imposed on them
(C) show a way in which Krontiris’s work illustrates
a “cautiously optimistic” assessment of
Renaissance women’s achievements
(D) summarize Krontiris’s view of the effect of
literacy on the lives of upper‐ and middle‐class
Renaissance women
(E) illustrate the way in which Krontiris’s study differs
from the studies done by Burckhardt and Kelly
Evaluation
e function of the nal sentence of the passage
is to indicate how Krontiris’s work takes neither a
completely positive nor completely negative view
of Renaissance women’s experiences—i.e., how
her work is representative of those authors who
are cautiously optimistic about the achievements
of Renaissance women.
A e passage discusses Krontiris’s work as an
example of the trend described in the latter
part of the rst paragraph and mentioned
in the rst line of the second paragraph.
e last sentence in the passage shows that
Krontiris’s work is in fact representative of
recent trends among feminist scholars.
B e last sentence in the passage states that
Renaissance women’s opposition to cultural
stereotypes was circumscribed, but it also
suggests that these women did gain some
power for themselves. us, the sentence
does not serve primarily to undermine the
argument that the women sought to oppose
social constraints.
C Correct. Krontiris’s work illustrates the
“cautiously optimistic” view by embracing
both the idea that Renaissance women
could gain a certain amount of power and
the idea that the extent of their opposition
was limited.
D e last sentence in the passage summarizes
Krontiris’s view, but that view does not,
according to the passage, take into account
the e ect of literacy on the members of a
particular social class.
E e main function of the nal sentence of
the passage is to take up the idea of the
cautiously optimistic assessment o ered
in the penultimate sentence. is does
mark a signi cant departure from both
Burckhardt and Kelly, but the distinction
between their work and that of other
feminist scholars is marked more clearly
earlier in the passage.
e correct answer is C.
536. The author of the passage implies that the women
studied by Krontiris are unusual in which of the
following ways?
(A) They faced obstacles less formidable than those
faced by other Renaissance women.
(B) They have been seen by historians as more
interesting than other Renaissance women.
(C) They were more concerned about recording
history accurately than were other Renaissance
women.
(D) Their perceptions are more likely to be
accessible to historians than are those of most
other Renaissance women.
(E) Their concerns are likely to be of greater interest
to feminist scholars than are the ideas of most
other Renaissance women.
Inference
e women Krontiris studied are unusual, the
author suggests, because they were literate, thus
putting them among the minority of Renaissance
women. at they could write, however, means
that their written re ections are part of the
historical record, whereas the direct impressions
of experiences had by Renaissance women who
could not write about their lives are lost to
history.
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499
A e author implies that the obstacles faced
by Krontiris’s subjects may have been
di erent from those faced by other women,
not that they were less formidable.
B e author does not imply that the women
studied by Krontiris are seen as more
interesting; rather, the author indicates that
their work is that which is available for study.
C e women Krontiris studies were able to
record their own history because they, unlike
most other Renaissance women, were literate.
is does not imply that they were more
concerned with recording history accurately.
D Correct. Because Krontiris’s subjects
were literate, they were able to write
down, and thus preserve for historians,
their perceptions in a way that most other
Renaissance women were not.
E e author does not suggest that feminist
scholars in general are more interested in
the concerns of middle‐ and upper‐class
literate women than they are with women of
other classes.
e correct answer is D.
Questions 537–540 refer to the passage on page 420.
537. The passage implies which of the following about the
ve asteroids mentioned in line 12 ?
(A) Their rotation rates are approximately the same.
(B) They have undergone approximately the same
number of collisions.
(C) They are monoliths.
(D) They are composed of fragments that have
escaped the gravity of larger asteroids.
(E) They were detected only recently.
Inference
In line 12, ve observed asteroids, refers to the ve
asteroids whose rotation rates are exceptions to
the strict limit on the rate of rotation found in
all other observed asteroids. ese ve asteroids
all have diameters smaller than 200meters.
e passage indicates that if asteroids were all
monoliths—that is, single rocks—then their
rotation rates would form a bell curve when
graphed, but if asteroids were piles of rubble, the
tail of the bell curve indicating very fast rotation
rates would be missing. Among asteroids larger
than 200meters, this tail is missing, and only the
ve asteroids described as exceptions have rotation
rates falling at the very high end of the bell curve.
A All that the passage states about the rotation
rates of these ve asteroids is that they do
not obey a strict limit. e passage does
not rule out that their rates of rotation are
signi cantly di erent from one another.
B According to the passage, frequent collisions
occur among asteroids. But the passage does
not suggest that asteroids that are of similar
sizes, or that have particularly high rotation
rates, will be similar in terms of the number
of collisions that they have undergone to
reach those distinctive states.
C Correct. e second paragraph states that
most small asteroids should be monolithic,
and the ve observed asteroids are all
smaller than 200meters in diameter.
D e ve asteroids are most likely not
composed of fragments because, as the
passage states, small asteroids should be
monoliths.
E e passage notes that researchers have
observed these ve asteroids, along with
others, but it does not indicate when these
asteroids were originally detected.
e correct answer is C.
538. The discovery of which of the following would call into
question the conclusion mentioned in line 16 ?
(A) An asteroid 100 meters in diameter rotating at a
rate of once per week
(B) An asteroid 150 meters in diameter rotating at a
rate of 20times per hour
(C) An asteroid 250 meters in diameter rotating at a
rate of once per week
(D) An asteroid 500 meters in diameter rotating at a
rate of once per hour
(E) An asteroid 1,000 meters in diameter rotating at
a rate of once every 24 hours
7.6 Reading Comprehension Answer Explanations
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Application
e conclusion that the text in line 16 points
to is that asteroids with diameters greater than
200 meters are multicomponent structures or rubble
piles. To call that conclusion into question, an
observation would have to suggest that asteroids
larger than 200 meters across are not such
multicomponent structures. According to the rst
paragraph, rubble piles cannot be fast rotators:
spinning faster than once every few hours would
make them y apart.
A Nothing in the passage suggests that the
behavior of an asteroid 100meters in
diameter is relevant to a conclusion about
the behavior of asteroids greater than
200meters in diameter.
B Nothing in the passage suggests that
the behavior of an asteroid 150meters
in diameter would have any e ect on
a conclusion about the constitution of
asteroids with diameters greater than
200meters.
C An asteroid 250meters in diameter rotating
at a rate of once per week would be rotating
at a slow enough rate to hold together a
pile of rubble. us, this observation would
be entirely consistent with the conclusion
about asteroids larger than 200meters in
diameter.
D Correct. Assuming that an asteroid
composed of a pile of rubble is of a great
enough density, a rotation rate greater than
one revolution every few hours would make
it y apart. So a 500-meter asteroid rotating
at a rate of once per hour—that is, faster
than the crucial speed—would y apart if it
were not a monolith. e conclusion states
that all asteroids larger than 200meters are
multicomponent structures (that is, are not
monoliths), so the discovery of a 500-meter
asteroid rotating at a rate of once an hour
would call into question that conclusion.
E An asteroid rotating at a rate of once
every 24hours would, regardless of size,
be rotating much more slowly than the
once every few hours that the passage claims
would make a pile of rubble of a su cient
density y apart. So an asteroid with a
diameter of 1,000meters that rotated once
per day could be a pile of rubble and not
con ict with the conclusion.
e correct answer is D.
539. According to the passage, which of the following
is a prediction that is based on the strength of the
gravitational attraction of small asteroids?
(A) Small asteroids will be few in number.
(B) Small asteroids will be monoliths.
(C) Small asteroids will collide with other asteroids
very rarely.
(D) Most small asteroids will have very fast rotation
rates.
(E) Almost no small asteroids will have very slow
rotation rates.
Supporting ideas
Regarding small asteroids, the second paragraph
states that they have feeble gravity. Any fragments
from impacts would escape that gravity, and thus,
the passage states, the small asteroids should be
monolithic.
A Small asteroids could be few in number, but
the passage does not o er such a prediction.
B Correct. is prediction is o ered in
the second paragraph, based on the fact
that small asteroids do not have strong
gravitational attraction. Any impact
fragments will easily escape the weak
gravitational attraction of the small
asteroids.
C e passage discusses large asteroids
collisions in more detail than small-
asteroid collisions, but it provides no basis
for predicting how often large and small
asteroids will, comparatively, be involved in
such collisions.
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D e rst paragraph indicates that the
rotation rates of small asteroids can exceed
the upper limit on the rotation rates of
large asteroids, but it does not indicate that
most small asteroids have rotation rates that
exceed this upper limit.
E e passage only indicates that there are few
observed exceptions to the upper limit on
rotation rates of large asteroids, and these
exceptions are all smaller than 200meters in
diameter; the passage does not indicate that
there are few small asteroids that have very
slow rotation rates.
e correct answer is B.
540. The author of the passage mentions “escape velocity”
(see line 22) in order to help explain which of the
following?
(A) The tendency for asteroids to become smaller
rather than larger over time
(B) The speed with which impact fragments
reassemble when they do not escape an
asteroid’s gravitational attraction after a collision
(C) The frequency with which collisions among
asteroids occur
(D) The rotation rates of asteroids smaller than 200
meters in diameter
(E) The tendency for large asteroids to persist after
collisions
Evaluation
is question asks about the purpose of the
author’s use of the phrase escape velocity in the
second paragraph. e author is discussing what
occurs after an asteroid collision, in which a
large asteroid might be blasted to bits. e bits,
according to the author, will move slower than
their mutual escape velocity—that is, the speed
at which they would have to move to get away
from each other and not reassemble, under the
in uence of gravity, into a rubble pile.
A e author is emphasizing the asteroid bits
that do not escape rather than those that do.
Asteroids may become smaller over time,
but the fact that most bits move slower
than their escape velocity would not help to
explain this shrinkage.
B at the bits of asteroid move slower than
their escape velocity helps explain why
the fragments reassemble, but it does not
help explain the speed with which they
reassemble.
C According to the author, asteroid collisions
occur frequently, but the escape velocity of
the resulting fragments does not help to
explain that frequency.
D e concept of escape velocity may help
explain why small asteroids are monoliths,
but it has no relevance, at least as far as the
passage indicates, to those asteroids’ rotation
rates.
E Correct. After a collision, it is the asteroid
fragments’ failure to reach escape velocity
that allows the fragments’ gravitational pull
to reassemble them into a rubble pile.
e correct answer is E.
Questions 541–543 refer to the passage on page 422.
541. The author of the passage mentions calculations about
tunneling time and barrier thickness in order to
(A) suggest that tunneling time is unrelated to
barrier thickness
(B) explain the evidence by which Wigner and
Eisenbud discovered the phenomenon of
tunneling
(C) describe data recently challenged by Raymond
Chiao and colleagues
(D) question why particles engaged in quantum
tunneling rarely achieve extremely high speeds
(E) explain the basis for Wigner and Eisenbud’s
hypothesis
Evaluation
is question asks why the author discusses
calculations about tunneling time and barrier
thickness. According to the passage, these
calculations provided the grounds for Wigner and
Eisenbud’s hypothesis that tunneling particles
may travel faster than light.
A e passage states that tunneling time
is related to barrier thickness, up to the
point at which tunneling time reaches a
maximum.
7.6 Reading Comprehension Answer Explanations
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B e passage indicates that the phenomenon
of tunneling was noted at least as early as
1932. It provides no evidence that Wigner
and Eisenbud discovered it.
C e passage uses Chiao’s work to support
the idea that tunneling particles may move
faster than light, not challenge it.
D e author describes calculations about
tunneling time and barrier thickness in
order to explain that particles engaged in
quantum tunneling may in fact achieve
extremely high speeds, not to explain the
rarity of the phenomenon.
E Correct. e calculations about tunneling
time and barrier thickness supported
Wigner and Eisenbud’s hypothesis that
quantum tunneling could occur at speeds
faster than that of light.
e correct answer is E.
542. The passage implies that if tunneling time reached no
maximum in increasing with barrier thickness, then
(A) tunneling speed would increase with barrier
thickness
(B) tunneling speed would decline with barrier
thickness
(C) tunneling speed would vary with barrier thickness
(D) tunneling speed would not be expected to
increase without limit
(E) successful tunneling would occur even less
frequently than it does
Inference
e passage states that because tunneling time
reaches a maximum, then tunneling speed must
increase as barrier thickness increases. But if
tunneling time did not reach such a maximum,
then speed need not increase without limit; the
particle could have as low a speed in thicker
barriers as in thinner ones and take longer to
tunnel through a barrier.
A If tunneling time could not reach a
maximum, then speed might increase,
decrease, or remain the same as barrier
thickness increases.
B If tunneling time could not reach a
maximum, then speed might increase,
decrease, or remain the same as barrier
thickness increases.
C Tunneling speed could vary with barrier
thickness if tunneling time could not reach
a maximum, but there is no basis in the
passage on which to conclude that this is
de nitely so.
D Correct. e tunneling particle could have
as low a speed in thicker barriers as in
thinner ones and simply take longer to make
its way through a thicker barrier.
E e passage states that the probability
of successful tunneling declines as the
thickness of the barrier increases. However,
it does not address the issue of whether
the di erences in probability of successful
tunneling are due to the greater time
required to go through thicker barriers.
e correct answer is D.
543. Which of the following statements about the earliest
scienti c investigators of quantum tunneling can be
inferred from the passage?
(A) They found it dif cult to increase barrier
thickness continually.
(B) They anticipated the later results of Chiao and
his colleagues.
(C) They did not suppose that tunneling particles
could travel faster than light.
(D) They were unable to observe instances of
successful tunneling.
(E) They made use of photons to study the
phenomenon of tunneling.
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Inference
is question asks about the earliest investigators
of quantum tunneling. e passage notes that
quantum tunneling’s extreme rapidity was
observed in 1932; thus, the earliest investigators
of this phenomenon knew of its existence at that
time. Not until 1955 did Wigner and Eisenbud
hypothesize that the particles traveled faster than
light. us, it is logical to infer that the earliest
investigators did not imagine such a speed.
A ere is nothing in the passage to suggest
that the earliest investigators of quantum
tunneling had di culty manipulating
barrier thickness.
B e passage states that Chiao and his
colleagues measured photons moving at 1.7
times the speed of light—but the passage
does not provide evidence that the earliest
investigators anticipated such speeds.
C Correct. e passage suggests that prior to
1955, investigators of quantum tunneling
had not hypothesized that the particles
could travel faster than the speed of light.
D e passage indicates that by 1932,
investigators had noted the rapidity of
quantum tunneling; although this does not
entail that they observed the phenomenon,
it is consistent with their having been able
to do so.
E e passage indicates that Chiao’s work
involves photons, but it does not indicate
the type of particles used or observed
by the earliest investigators of the
phenomenon.
e correct answer is C.
7.6 Reading Comprehension Answer Explanations
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8.0 Critical Reasoning
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8.0 Critical Reasoning
8.0 Critical Reasoning
Critical reasoning questions appear in the Verbal section of the GMAT
® exam. e Verbal section uses
multiple‐choice questions to measure your ability to read and comprehend written material, to reason
and to evaluate arguments, and to correct written material to conform to standard written English.
Because the Verbal section includes content from a variety of topics, you may be generally familiar with
some of the material; however, neither the passages nor the questions assume knowledge of the topics
discussed. Critical reasoning questions are intermingled with reading comprehension and sentence
correction questions throughout the Verbal section of the test.
You will have 75 minutes to complete the Verbal section, or about 1¾ minutes to answer each question.
Although critical reasoning questions are based on written passages, these passages are shorter than
reading comprehension passages. ey tend to be less than 100 words in length and generally are
followed by one or two questions. For these questions, you will see a split computer screen. e written
passage will remain visible at the top of the screen. In turn, each associated question will appear either
below or above the relevant passage. You will see only one question at a time.
Critical reasoning questions are designed to test the reasoning skills involved in (1) making arguments,
(2) evaluating arguments, and (3) formulating or evaluating a plan of action. e materials on which
questions are based are drawn from a variety of sources. e GMAT exam does not expect any
familiarity with the subject matter of those materials.
In these questions, you are to analyze the situation on which each question is based, and then select the
answer choice that most appropriately answers the question. Begin by reading the passages carefully,
then reading the five answer choices. If the correct answer is not immediately obvious to you, see
whether you can eliminate some of the wrong answers. Reading the passage a second time may be
helpful in illuminating subtleties that were not immediately evident.
Answering critical reasoning questions requires no specialized knowledge of any particular field; you
don’t have to have knowledge of the terminology and conventions of formal logic. e sample critical
reasoning questions in this chapter illustrate the variety of topics the test may cover, the kinds of
questions it may ask, and the level of analysis it requires.
e following pages describe what critical reasoning questions are designed to measure and present the
directions that will precede questions of this type. Sample questions and explanations of the correct
answers follow.
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8.1 What Is Measured
Critical reasoning questions are designed to provide one measure of your ability to reason e ectively in
the following areas:
• Argument construction
Questions in this category may ask you to recognize such things as the basic structure of an
argument, properly drawn conclusions, underlying assumptions, well‐supported explanatory
hypotheses, and parallels between structurally similar arguments.
• Argument evaluation
ese questions may ask you to analyze a given argument and to recognize such things as factors
that would strengthen or weaken the given argument; reasoning errors committed in making that
argument; and aspects of the method by which the argument proceeds.
• Formulating and evaluating a plan of action
is type of question may ask you to recognize such things as the relative appropriateness,
e ectiveness, or e ciency of di erent plans of action, factors that would strengthen or weaken the
prospects of success of a proposed plan of action, and assumptions underlying a proposed plan of
action.
8.2 Test-Taking Strategies
1. Read very carefully the set of statements on which a question is based.
Pay close attention to
• what is put forward as factual information
• what is not said but necessarily follows from what is said
• what is claimed to follow from facts that have been put forward
• how well substantiated are any claims that a particular conclusion follows from the facts that have
been put forward
In reading the arguments, it is important to pay attention to the logical reasoning used; the actual
truth of statements portrayed as fact is not important.
2. Identify the conclusion.
e conclusion does not necessarily come at the end of the text; it may come somewhere in the
middle or even at the beginning. Be alert to clues in the text that an argument follows logically from
another statement or statements in the text.
3. Determine exactly what each question asks.
You might find it helpful to read the question first, before reading the material on which it is based;
don’t assume that you know what you will be asked about an argument. An argument may have
obvious flaws, and one question may ask you to detect them. But another question may direct you to
select the one answer choice that does NOT describe a flaw in the argument.
4. Read all the answer choices carefully.
Do not assume that a given answer is the best without first reading all the choices.
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8.3 The Directions
ese are the directions you will see for critical reasoning questions when you take the GMAT exam. If
you read them carefully and understand them clearly before going to sit for the test, you will not need to
spend too much time reviewing them when you are at the test center and the test is under way.
For these questions, select the best of the answer choices given.
8.3 Critical Reasoning The Directions
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544. Neuroscientist: Memory evolved to help animals react
appropriately to situations they encounter by drawing
on the past experience of similar situations. But this
does not require that animals perfectly recall every
detail of all their experiences. Instead, to function well,
memory should generalize from past experiences that
are similar to the current one.
The neuroscientist’s statements, if true, most strongly
support which of the following conclusions?
(A) At least some animals perfectly recall every
detail of at least some past experiences.
(B) Perfectly recalling every detail of all their past
experiences could help at least some animals
react more appropriately than they otherwise
would to new situations they encounter.
(C) Generalizing from past experiences requires
clear memories of most if not all the details of
those experiences.
(D) Recalling every detail of all past experiences
would be incompatible with any ability to
generalize from those experiences.
(E) Animals can often react more appropriately
than they otherwise would to situations they
encounter if they draw on generalizations from
past experiences of similar situations.
545. Astronomer: Most stars are born in groups of
thousands, each star in a group forming from the
same parent cloud of gas. Each cloud has a unique,
homogeneous chemical composition. Therefore,
whenever two stars have the same chemical
composition as each other, they must have originated
from the same cloud of gas.
Which of the following, if true, would most strengthen
the astronomer’s argument?
(A) In some groups of stars, not every star
originated from the same parent cloud of gas.
(B) Clouds of gas of similar or identical chemical
composition may be remote from each other.
(C) Whenever a star forms, it inherits the chemical
composition of its parent cloud of gas.
(D) Many stars in vastly different parts of the
universe are quite similar in their chemical
compositions.
(E) Astronomers can at least sometimes precisely
determine whether a star has the same chemical
composition as its parent cloud of gas.
546. With employer-paid training, workers have the potential
to become more productive not only in their present
employment but also in any number of jobs with
different employers. To increase the productivity of their
workforce, many rms are planning to maintain or even
increase their investments in worker training. But some
training experts object that if a trained worker is hired
away by another rm, the employer that paid for the
training has merely subsidized a competitor. They note
that such hiring has been on the rise in recent years.
Which of the following would, if true, contribute most
to defeating the training experts’ objection to the rms’
strategy?
(A) Firms that promise opportunities for
advancement to their employees get, on
average, somewhat larger numbers of job
applications from untrained workers than do
rms that make no such promise.
8.4 Practice Questions
Each of the critical reasoning questions is based on a short argument, a set of statements, or a plan of
action. For each question, select the best answer of the choices given.
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(B) In many industries, employees who take
continuing-education courses are more
competitive in the job market.
(C) More and more educational and training
institutions are offering reduced tuition fees to
rms that subsidize worker training.
(D) Research shows that workers whose training is
wholly or partially subsidized by their employer
tend to get at least as much training as do
workers who pay for all their own training.
(E) For most rms that invest in training their
employees, the value added by that investment
in employees who stay exceeds the value lost
through other employees’ leaving to work for
other companies.
547. Candle Corporation’s television stations are likely to
have more income from advertisers than previously.
This is because advertisers prefer to reach people
in the 18‐ to 49‐year‐old age group and the number
of people in that group watching Candle television is
increasing. Furthermore, among Candle viewers, the
percentage of viewers 18 to 49 years old is increasing.
Which of the following, if true, would most strengthen
the argument that Candle Corporation will receive more
income from advertisers?
(A) Advertisers carefully monitor the demographic
characteristics of television audiences and
purchase advertising time to reach the audiences
they prefer to reach.
(B) Among people over 49 years old, fewer viewers
of Candle stations buy products advertised on
television than do viewers of other stations.
(C) There will be increasingly more advertisements
on television that are directed at viewers who are
over 49 years old.
(D) Candle stations plan to show reruns of television
shows during hours when other stations run
shows for the rst time.
(E) People 18 to 49 years old generally have less
disposable income to spend than do people over
49 years old.
548. A provincial government plans to raise the gasoline
tax to give people an incentive to drive less, reducing
traf c congestion in the long term. However, skeptics
point out that most people in the province live in areas
where cars are the only viable transportation to jobs
and stores and therefore cannot greatly change their
driving habits in response to higher gasoline prices.
In light of the skeptics’ objection, which of the
following, if true, would most logically support the
prediction that the government’s plan will achieve its
goal of reducing traf c congestion?
(A) The revenue from the tax will be used to
make public transportation a viable means of
transportation to jobs and stores for far more
people.
(B) The tax will encourage many residents to switch
to more fuel‐ef cient cars, reducing air pollution
and other problems.
(C) Because gasoline has been underpriced for
decades, the province has many neighborhoods
where cars are the only viable means of
transportation.
(D) Most residents who cannot greatly change
their driving habits could compensate for high
gasoline prices by reducing other expenses.
(E) Traf c congestion is an especially serious
problem for people for whom cars are the only
viable means of transportation.
8.4 Critical Reasoning Practice Questions
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549. Editorial: The roof of Northtown’s municipal equipment‐
storage building collapsed under the weight of last
week’s heavy snowfall. The building was constructed
recently and met local building‐safety codes in every
particular, except that the nails used for attaching roof
supports to the building’s columns were of a smaller
size than the codes specify for this purpose. Clearly,
this collapse exempli es how even a single, apparently
insigni cant departure from safety standards can have
severe consequences.
Which of the following, if true, most seriously weakens
the editorial’s argument?
(A) The only other buildings to suffer roof collapses
from the weight of the snowfall were older
buildings constructed according to less exacting
standards than those in the codes.
(B) The amount of snow that accumulated on the
roof of the equipment‐storage building was
greater than the predicted maximum that was
used in drawing up the safety codes.
(C) Because the equipment‐storage building was not
intended for human occupation, some safety‐
code provisions that would have applied to an
of ce building did not apply to it.
(D) The municipality of Northtown itself has the
responsibility for ensuring that buildings
constructed within its boundaries meet the
provisions of the building‐safety codes.
(E) Because the equipment‐storage building was
used for storing snow‐removal equipment, the
building was almost completely empty when the
roof collapsed.
550. Political theorist: Even with the best spies, area
experts, and satellite surveillance, foreign policy
assessments can still lack important information.
In such circumstances intuitive judgment is vital. A
national leader with such judgment can make good
decisions about foreign policy even when current
information is incomplete, since __________.
Which of the following, if true, most logically completes
the argument?
(A) the central reason for failure in foreign policy
decision making is the absence of critical
information
(B) those leaders whose foreign policy decisions
have been highly ranked have also been found to
have good intuitive judgment
(C) both intuitive judgment and good information are
required for sound decision making
(D) good foreign policy decisions often lead to
improved methods of gathering information
(E) intuitive judgment can produce good decisions
based on past experience, even when there are
important gaps in current information
551. During the earliest period of industrialization in Britain,
steam engines were more expensive to build and
operate than either windmills or water mills, the other
practicable sources of power for factories. Yet despite
their signi cant cost disadvantage, steam‐powered
factories were built in large numbers well before technical
improvements brought their cost down. Furthermore,
they were built even in regions where geographical
conditions permitted the construction of wind‐ and water‐
powered factories close to major markets.
Which of the following, if true, most helps to explain
the proliferation of steam‐powered factories during the
earliest period of industrialization in Britain?
(A) In many areas of Britain, there were fewer steam‐
powered factories than wind‐ or water‐powered
factories in the earliest period of industrialization.
(B) Unlike wind‐ or water‐powered factories, steam‐
powered factories were fueled with coal, which
sometimes had to be transported signi cant
distances from the mine to the site of the factory.
(C) It was both dif cult and expensive to convert
a factory from wind power or water power to
steam power.
(D) In the early period of industrialization, many
goods sold in towns and cities could not be
mass‐produced in factories.
(E) In Britain, the number of sites where a wind‐
or water‐powered factory could be built was
insuf cient to provide for all of the demand for
factory‐produced goods at the time.
552. Snowmaking machines work by spraying a mist that
freezes immediately on contact with cold air. Because
the sudden freezing kills bacteria, QuickFreeze is
planning to market a wastewater puri cation system
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that works on the same principle. The process
works only when temperatures are cold, however,
so municipalities using it will still need to maintain a
conventional system.
Which of the following, if true, provides the strongest
grounds for a prediction that municipalities will buy
QuickFreeze’s puri cation system despite the need to
maintain a conventional puri cation system as well?
(A) Bacteria are not the only impurities that must be
removed from wastewater.
(B) Many municipalities have old wastewater
puri cation systems that need to be replaced.
(C) Conventional wastewater puri cation systems
have not been fully successful in killing bacteria
at cold temperatures.
(D) During times of warm weather, when it is not in
use, QuickFreeze’s puri cation system requires
relatively little maintenance.
(E) Places where the winters are cold rarely have a
problem of water shortage.
553. Suncorp, a new corporation with limited funds, has
been clearing large sections of the tropical Amazon
forest for cattle ranching. This practice continues
even though greater pro ts can be made from rubber
tapping, which does not destroy the forest, than from
cattle ranching, which does destroy the forest.
Which of the following, if true, most helps to explain
why Suncorp has been pursuing the less pro table of
the two economic activities mentioned above?
(A) The soil of the Amazon forest is very rich in
nutrients that are important in the development
of grazing lands.
(B) Cattle‐ranching operations that are located in
tropical climates are more pro table than cattle‐
ranching operations that are located in cold‐
weather climates.
(C) In certain districts, pro ts made from cattle
ranching are more heavily taxed than pro ts
made from any other industry.
(D) Some of the cattle that are raised on land
cleared in the Amazon are killed by wildcats.
(E) The amount of money required to begin a rubber‐
tapping operation is twice as high as the amount
needed to begin a cattle ranch.
554. Archaeologists use technology to analyze ancient sites.
It is likely that this technology will advance considerably
in the near future, allowing archaeologists to gather
more information than is currently possible. If they
study certain sites now, they risk contaminating or
compromising them for future studies. Therefore, in
order to maximize the potential for gathering knowledge
in the long run, a team of archaeologists plans to delay
the examination of a newly excavated site.
Which of the following would be most useful to
investigate for the purpose of evaluating the plan’s
prospects for achieving its goal?
(A) Whether any of the contents of the site will
signi cantly deteriorate before the anticipated
technology is available
(B) Whether there will continue to be improvements
on the relevant technology
(C) Whether the team can study a site other than the
newly excavated site for the time being
(D) Whether the site was inhabited by a very ancient
culture
(E) Whether the anticipated technology will damage
objects under study
555. A newly discovered painting seems to be the work
of one of two seventeenth‐century artists, either the
northern German Johannes Drechen or the Frenchman
Louis Birelle, who sometimes painted in the same
style as Drechen. Analysis of the carved picture frame,
which has been identi ed as the painting’s original
seventeenth‐century frame, showed that it is made of
wood found widely in northern Germany at the time, but
rare in the part of France where Birelle lived. This shows
that the painting is most likely the work of Drechen.
Which of the following is an assumption that the
argument requires?
(A) The frame was made from wood local to the
region where the picture was painted.
(B) Drechen is unlikely to have ever visited the home
region of Birelle in France.
(C) Sometimes a painting so resembles others of its
era that no expert is able to con dently decide
who painted it.
(D) The painter of the picture chose the frame for
the picture.
(E) The carving style of the picture frame is not
typical of any speci c region of Europe.
8.4 Critical Reasoning Practice Questions
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556. Beginning in 1966 all new cars sold in Morodia were
required to have safety belts and power steering.
Previously, most cars in Morodia were without these
features. Safety belts help to prevent injuries in
collisions, and power steering helps to avoid collisions
in the rst place. But even though in 1966 one-seventh
of the cars in Morodia were replaced with new cars,
the number of car collisions and collision-related
injuries did not decline.
Which of the following, if true about Morodia, most helps
to explain why the number of collisions and collision-
related injuries in Morodia failed to decline in 1966?
(A) Because of a driver-education campaign, most
drivers and passengers in cars that did have
safety belts used them in 1966.
(B) Most of the new cars bought in 1966 were
bought in the months of January and February.
(C) In 1965, substantially more than one-seventh of
the cars in Morodia were replaced with new cars.
(D) An excessive reliance on the new safety features
led many owners of new cars to drive less
cautiously in 1966 than before.
(E) The seat belts and power steering put into new
cars sold in 1966 had to undergo strict quality-
control inspections by manufacturers, whether the
cars were manufactured in Morodia or not.
557. In order to reduce the number of items damaged
while in transit to customers, packaging consultants
recommended that the TrueSave mail‐order company
increase the amount of packing material so as to ll
any empty spaces in its cartons. Accordingly, TrueSave
of cials instructed the company’s packers to use
more packing material than before, and the packers
zealously acted on these instructions and used as
much as they could. Nevertheless, customer reports
of damaged items rose somewhat.
Which of the following, if true, most helps to explain
why acting on the consultants’ recommendation failed
to achieve its goal?
(A) The change in packing policy led to an increase
in expenditure on packing material and labor.
(B) When packing material is compressed too densely,
it loses some of its capacity to absorb shock.
(C) The amount of packing material used in a carton
does not signi cantly in uence the ease with
which a customer can unpack the package.
(D) Most of the goods that TrueSave ships are
electronic products that are highly vulnerable to
being damaged in transit.
(E) TrueSave has lost some of its regular customers
as a result of the high number of damaged items
they received.
558. Parland’s alligator population has been declining in
recent years, primarily because of hunting. Alligators
prey heavily on a species of freshwater sh that is highly
valued as food by Parlanders, who had hoped that
the decline in the alligator population would lead to an
increase in the numbers of these sh available for human
consumption. Yet the population of this sh species has
also declined, even though the annual number caught for
human consumption has not increased.
Which of the following, if true, most helps to explain
the decline in the population of the sh species?
(A) The decline in the alligator population has meant
that shers can work in some parts of lakes and
rivers that were formerly too dangerous.
(B) Over the last few years, Parland’s commercial
shing enterprises have increased the number of
shing boats they use.
(C) The main predator of these sh is another
species of sh on which alligators also prey.
(D) Many Parlanders who hunt alligators do so
because of the high market price of alligator
skins, not because of the threat alligators pose
to the sh population.
(E) In several neighboring countries through which
Parland’s rivers also ow, alligators are at risk of
extinction as a result of extensive hunting.
559. A certain automaker aims to increase its market
share by deeply discounting its vehicles’ prices for
the next several months. The discounts will cut into
pro ts, butbecause they will be heavily advertised the
manufacturer hopes that they will attract buyers away
from rival manufacturers’ cars. In the longer term, the
automaker envisions that customers initially attracted
by the discounts may become loyal customers.
In assessing the plan’s chances of achieving its aim, it
would be most useful to know which of the following?
(A) Whether the automaker’s competitors are likely
to respond by offering deep discounts on their
own products
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(B) Whether the advertisements will be created by
the manufacturer’s current advertising agency
(C) Whether some of the automaker’s models will be
more deeply discounted than others
(D) Whether the automaker will be able to cut costs
suf ciently to maintain pro t margins even when
the discounts are in effect
(E) Whether an alternative strategy might enable the
automaker to enhance its pro tability while holding
a constant or diminishing share of the market
560. In virtually any industry, technological improvements
increase labor productivity, which is the output of
goods and services per person‐hour worked. In
Parland’s industries, labor productivity is signi cantly
higher than it is in Vergia’s industries. Clearly,
therefore, Parland’s industries must, on the whole, be
further advanced technologically than Vergia’s are.
The argument is most vulnerable to which of the
following criticisms?
(A) It offers a conclusion that is no more than a
paraphrase of one of the pieces of information
provided in its support.
(B) It presents as evidence in support of a claim
information that is inconsistent with other
evidence presented in support of the same claim.
(C) It takes one possible cause of a condition to
be the actual cause of that condition without
considering any other possible causes.
(D) It takes a condition to be the effect of something
that happened only after the condition already
existed.
(E) It makes a distinction that presupposes the truth
of the conclusion that is to be established.
561. Chaco Canyon, a settlement of the ancient Anasazi
culture in North America, had massive buildings.
It must have been a major Anasazi center.
Analysis of wood samples shows that some of the
timber for the buildings came from the Chuska and
San Mateo mountains, 50 miles from Chaco Canyon.
Only a major cultural center would have the
organizational power to import timber from 50
miles away.
In the argument given, the two portions in boldface
play which of the following roles?
(A) The rst is a premise used to support the
argument’s main conclusion; the second is the
argument’s main conclusion.
(B) The rst is the argument’s main conclusion;
the second is a premise used to support that
conclusion.
(C) The rst is one of two premises used to support
the argument’s main conclusion; the second is
the other of those two premises.
(D) The rst is a premise used to support the
argument’s main conclusion; the second is a
premise used to support another conclusion
drawn in the argument.
(E) The rst is inferred from another statement in the
argument; the second is inferred from the rst.
562. The Maxilux car company’s design for its new luxury
model, the Max 100, included a special design for the
tires that was intended to complement the model’s
image. The winning bid for supplying these tires was
submitted by Rubco. Analysts concluded that the
bid would only just cover Rubco’s costs on the tires,
but Rubco executives claim that winning the bid will
actually make a pro t for the company.
Which of the following, if true, most strongly justi es
the claim made by Rubco’s executives?
(A) In any Maxilux model, the spare tire is exactly
the same make and model as the tires that are
mounted on the wheels.
(B) Rubco holds exclusive contracts to supply
Maxilux with the tires for a number of other
models made by Maxilux.
(C) The production facilities for the Max 100 and
those for the tires to be supplied by Rubco are
located very near each other.
(D) When people who have purchased a carefully
designed luxury automobile need to replace a
worn part of it, they almost invariably replace it
with a part of exactly the same make and type.
(E) When Maxilux awarded the tire contract to
Rubco, the only criterion on which Rubco’s bid
was clearly ahead of its competitors’ bids was
price.
8.4 Critical Reasoning Practice Questions
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563. Which of the following most logically completes the
passage?
Most bicycle helmets provide good protection for the
top and back of the head, but little or no protection for
the temple regions on the sides of the head. A study
ofhead injuries resulting from bicycle accidents showed
that a large proportion were caused by blows to the
temple area. Therefore, if bicycle helmets protected this
area, the risk of serious head injury in bicycle accidents
would be greatly reduced, especially since ________.
(A) among the bicyclists included in the study’s
sample of head injuries, only a very small
proportion had been wearing a helmet at the
time of their accident
(B) even those bicyclists who regularly wear helmets
have a poor understanding of the degree and
kind of protection that helmets afford
(C) a helmet that included protection for the temples
would have to be somewhat larger and heavier
than current helmets
(D) the bone in the temple area is relatively thin and
impacts in that area are thus very likely to cause
brain injury
(E) bicyclists generally land on their arm or shoulder
when they fall to the side, which reduces the
likelihood of severe impacts on the side of the head
564. Which of the following most logically completes the
argument?
In a typical year, Innovair’s airplanes are involved in
35 collisions while parked or being towed in airports,
with a resulting yearly cost of $1,000,000 for repairs.
To reduce the frequency of ground collisions, Innovair
will begin giving its ground crews additional training,
at an annual cost of $500,000. Although this will cut
the number of ground collisions by about half at best,
the drop in repair costs can be expected to be much
greater, since __________.
(A) most ground collisions happen when ground
crews are rushing to minimize the time a delayed
airplane spends on the ground
(B) a ground collision typically occurs when there
are no passengers on the airplane
(C) the additional training will focus on helping
ground crews avoid those kinds of ground
collisions that cause the most costly damage
(D) the $500,000 cost gure for the additional
training of ground crews includes the wages that
those crews will earn during the time spent in
actual training
(E) most ground collisions have been caused by the
least experienced ground‐crew members
565. Hunter: Many people blame hunters alone for
the decline in Greenrock National Forest’s deer
population over the past ten years. Yet clearly,
black bears have also played an important role
in this decline. In the past ten years, the forest’s
protected black bear population has risen sharply, and
examination of black bears found dead in the forest
during the deer hunting season showed that a number
of them had recently fed on deer.
In the hunter’s argument, the portion in boldface plays
which of the following roles?
(A) It is the main conclusion of the argument.
(B) It is a nding that the argument seeks to explain.
(C) It is an explanation that the argument concludes
is correct.
(D) It provides evidence in support of the main
conclusion of the argument.
(E) It introduces a judgment that the argument
opposes.
566. Many agriculturally intensive areas of the world are
beginning to encounter water scarcity problems. As
a result, many farmers in these areas are likely to
reduce their output as the water supply they need in
order to maintain production shrinks. However, one
group of farmers in such a region plans to increase
their production by implementing techniques for water
conservation.
Which of the following, if true, would most strongly
support the prediction that the group’s plan will
succeed?
(A) Farmers that can gain a larger share of the food
market in their regions will be better positioned
to control more water resources.
(B) Most agricultural practices in areas with water
shortages are water‐intensive.
(C) Other regions of the world not facing water
shortages are likely to make up for the reduction
in agricultural output.
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(D) Demand for agricultural products in the group’s
region is not expected to decline.
(E) More than half the water used for agriculture
in the farmers’ region is lost to evaporation or
leakage from irrigation channels.
567. Physician: The hormone melatonin has shown promise
as a medication for sleep disorders when taken in
synthesized form. Because the long‐term side effects
of synthetic melatonin are unknown, however, I cannot
recommend its use at this time.
Patient: Your position is inconsistent with your usual
practice. You prescribe many medications that you
know have serious side effects, so concern about side
effects cannot be the real reason you will not prescribe
melatonin.
The patient’s argument is awed because it fails to
consider that
(A) the side effects of synthetic melatonin might
be different from those of naturally produced
melatonin
(B) it is possible that the physician does not believe
that melatonin has been conclusively shown to
be effective
(C) sleep disorders, if left untreated, might lead to
serious medical complications
(D) the side effects of a medication can take some
time to manifest themselves
(E) known risks can be weighed against known
bene ts, but unknown risks cannot
568. Hollywood restaurant is replacing some of its standard
tables with tall tables and stools. The restaurant
already lls every available seat during its operating
hours, and the change in seating arrangements will
not result in an increase in the restaurant’s seating
capacity. Nonetheless, the restaurant’s management
expects revenue to increase as a result of the seating
change without any concurrent change in menu,
prices, or operating hours.
Which of the following, if true, provides the best reason
for the expectation?
(A) One of the taller tables takes up less oor space
than one of the standard tables.
(B) Diners seated on stools typically do not linger over
dinner as long as diners seated at standard tables.
(C) Since the restaurant will replace only some of its
standard tables, it can continue to accommodate
customers who do not care for the taller tables.
(D) Few diners are likely to avoid the restaurant
because of the new seating arrangement.
(E) The standard tables being replaced by tall tables
would otherwise have to be replaced with new
standard tables at a greater expense.
569. A major network news organization experienced a
drop in viewership in the week following the airing of a
controversial report on the economy. The network also
received a very large number of complaints regarding
the report. The network, however, maintains that
negative reactions to the report had nothing to do with
its loss of viewers.
Which of the following, if true, most strongly supports
the network’s position?
(A) The other major network news organizations
reported similar reductions in viewership during
the same week.
(B) The viewers who registered complaints with
the network were regular viewers of the news
organization’s programs.
(C) Major network news organizations publicly
attribute drops in viewership to their own reports
only when they receive complaints about those
reports.
(D) This was not the rst time that this network news
organization has aired a controversial report
on the economy that has inspired viewers to
complain to the network.
(E) Most network news viewers rely on network
news broadcasts as their primary source of
information regarding the economy.
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570. Only a reduction of 10 percent in the number of
scheduled ights using Greentown’s airport will allow
the delays that are so common there to be avoided.
Hevelia airstrip, 40 miles away, would, if upgraded
and expanded, be an attractive alternative for fully
20 percent of the passengers using Greentown airport.
Nevertheless, experts reject the claim that turning
Hevelia into a full‐service airport would end the chronic
delays at Greentown.
Which of the following, if true, most helps to justify the
experts’ position?
(A) Turning Hevelia into a full‐service airport would
require not only substantial construction at the
airport itself, but also the construction of new
access highways.
(B) A second largely undeveloped airstrip close to
Greentown airport would be a more attractive
alternative than Hevelia for many passengers
who now use Greentown.
(C) Hevelia airstrip lies in a relatively undeveloped
area but would, if it became a full‐service airport,
be a magnet for commercial and residential
development.
(D) If an airplane has to wait to land, the extra jet
fuel required adds signi cantly to the airline’s
costs.
(E) Several airlines use Greentown as a regional hub,
so that most ights landing at Greentown have
many passengers who then take different ights
to reach their nal destinations.
571. For similar cars and comparable drivers, automobile
insurance for collision damage has always cost more
in Greatport than in Fairmont. Police studies, however,
show that cars owned by Greatport residents are, on
average, slightly less likely to be involved in a collision
than cars in Fairmont. Clearly, therefore, insurance
companies are making a greater pro t on collision‐
damage insurance in Greatport than in Fairmont.
In evaluating the argument, it would be most useful to
compare
(A) the level of traf c congestion in Greatport with
the level of traf c congestion in Fairmont
(B) the cost of repairing collision damage in
Greatport with the cost of repairing collision
damage in Fairmont
(C) the rates Greatport residents pay for other
forms of insurance with the rates paid for similar
insurance by residents of Fairmont
(D) the condition of Greatport’s roads and streets with
the condition of Fairmont’s roads and streets
(E) the cost of collision‐damage insurance in
Greatport and Fairmont with that in other cities
572. The air quality board recently informed Coffee Roast,
a small coffee roasting rm, of a complaint regarding
the smoke from its roaster. Recently enacted air quality
regulations require machines roasting more than
10 pounds of coffee to be equipped with expensive
smoke‐dissipating afterburners. The rm, however,
roasts only 8 pounds of coffee at a time. Nevertheless,
the company has decided to purchase and install an
afterburner.
Which of the following, if true, most strongly supports
the rm’s decision?
(A) Until settling on the new air quality regulations,
the board had debated whether to require
afterburners for machines roasting more than
5 pounds of coffee at a time.
(B) Coffee roasted in a machine equipped with an
afterburner has its avor subtly altered.
(C) The cost to the rm of an afterburner is less than
the cost of replacing its roaster with a smaller one.
(D) Fewer complaints are reported in areas that
maintain strict rules regarding afterburners.
(E) The rm has reason to fear that negative publicity
regarding the complaints could result in lost sales.
573. The tulu, a popular ornamental plant, does not
reproduce naturally, and is only bred and sold by
specialized horticultural companies. Unfortunately, the
tulu is easily devastated by a contagious fungal rot.
The government ministry plans to reassure worried
gardeners by requiring all tulu plants to be tested
for fungal rot before being sold. However, infected
plants less than 30 weeks old have generally not built
up enough fungal rot in their systems to be detected
reliably. And many tulu plants are sold before they are
24 weeks old.
Which of the following, if performed by the government
ministry, could logically be expected to overcome the
problem with their plan to test for the fungal rot?
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(A) Releasing a general announcement that tulu
plants less than 30 weeks old cannot be
effectively tested for fungal rot
(B) Requiring all tulu plants less than 30 weeks old
to be labeled as such
(C) Researching possible ways to test tulu plants
less than 24 weeks old for fungal rot
(D) Ensuring that tulu plants not be sold before they
are 30 weeks old
(E) Quarantining all tulu plants from horticultural
companies at which any case of fungal rot has
been detected until those tulu plants can be
tested for fungal rot
574. People who do regular volunteer work tend to live longer,
on average, than people who do not. It has been found that
“doing good,” a category that certainly includes volunteer
work, releases endorphins, the brain’s natural opiates,
which induce in people a feeling of well‐being. Clearly, there
is a connection: Regular releases of endorphins must in
some way help to extend people’s lives.
Which of the following, if true, most seriously
undermines the force of the evidence given as support
for the hypothesis that endorphins promote longevity?
(A) People who do regular volunteer work are
only somewhat more likely than others to
characterize the work they do for a living as
“doing good.”
(B) Although extremely high levels of endorphins
could be harmful to health, such levels are never
reached as a result of the natural release of
endorphins.
(C) There are many people who have done some
volunteer work but who do not do such work
regularly.
(D) People tend not to become involved in regular
volunteer work unless they are healthy and
energetic to begin with.
(E) Releases of endorphins are responsible for the
sense of well‐being experienced by many long‐
distance runners while running.
575. In Mernia commercial fossil hunters often sell
important fossils they have found, not to universities or
museums, but to individual collectors, who pay much
better but generally do not allow researchers access
to their collections. To increase the number of fossils
available for research, some legislators propose
requiring all fossils that are found in Mernia to be sold
only to universities or museums.
Which of the following, if true, most strongly indicates
that the legislators’ proposal will fail to achieve its goal?
(A) Some fossil hunters in Mernia are not
commercial fossil hunters, but rather are
amateurs who keep the fossils that they nd.
(B) Most fossils found in Mernia are common types
that have little scienti c interest.
(C) Commercial fossil hunters in Mernia currently sell
some of the fossils they nd to universities and
museums.
(D) Many universities in Mernia do not engage in
fossil research.
(E) Most fossils are found by commercial fossil
hunters, and they would give up looking for
fossils if they were no longer allowed to sell to
individual collectors.
576. The Eurasian ruffe, a sh species inadvertently
introduced into North America’s Great Lakes in recent
years, feeds on the eggs of lake white sh, a native
species, thus threatening the lakes’ natural ecosystem.
To help track the ruffe’s spread, government agencies
have produced wallet‐sized cards about the ruffe. The
cards contain pictures of the ruffe and explain the
danger they pose; the cards also request anglers to
report any ruffe they catch.
Which of the following, if true, would provide most
support for the prediction that the agencies’ action will
have its intended effect?
(A) The ruffe has spiny ns that make it unattractive
as prey.
(B) Ruffe generally feed at night, but most
recreational shing on the Great Lakes is done
during daytime hours.
(C) Most people who sh recreationally on the Great
Lakes are interested in the preservation of the lake
white sh because it is a highly prized game sh.
(D) The ruffe is one of several nonnative species in
the Great Lakes whose existence threatens the
survival of lake white sh populations there.
(E) The bait that most people use when shing for
white sh on the Great Lakes is not attractive to
ruffe.
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577. Which of the following most logically completes the
argument below?
Although the number of large arti cial satellites orbiting
the Earth is small compared to the number of small
pieces of debris in orbit, the large satellites interfere more
seriously with telescope observations because of the
strong re ections they produce. Because many of those
large satellites have ceased to function, the proposal
has recently been made to eliminate interference from
nonfunctioning satellites by exploding them in space. This
proposal, however, is ill conceived, since ________.
(A) many nonfunctioning satellites remain in orbit for
years
(B) for satellites that have ceased to function,
repairing them while they are in orbit would be
prohibitively expensive
(C) there are no known previous instances of
satellites’ having been exploded on purpose
(D) the only way to make telescope observations
without any interference from debris in orbit is
to use telescopes launched into extremely high
orbits around the Earth
(E) a greatly increased number of small particles
in Earth’s orbit would result in a blanket of
re ections that would make certain valuable
telescope observations impossible
578. Thyrian lawmaker: Thyria’s Cheese Importation Board
inspects all cheese shipments to Thyria and rejects
shipments not meeting speci ed standards. Yet only
1percent is ever rejected. Therefore, since the health
consequences and associated economic costs of not
rejecting that 1 percent are negligible, whereas the
board’s operating costs are considerable, for economic
reasons alone the board should be disbanded.
Consultant: I disagree. The threat of having their
shipments rejected deters many cheese exporters
from shipping substandard product.
The consultant responds to the lawmaker’s argumentby
(A) rejecting the lawmaker’s argument while proposing
that the standards according to which the board
inspects imported cheese should be raised
(B) providing evidence that the lawmaker’s argument
has signi cantly overestimated the cost of
maintaining the board
(C) objecting to the lawmaker’s introducing into the
discussion factors that are not strictly economic
(D) pointing out a bene t of maintaining the board, which
the lawmaker’s argument has failed to consider
(E) shifting the discussion from the argument at hand to
an attack on the integrity of the cheese inspectors
579. The growing popularity of computer‐based activities
was widely expected to result in a decline in television
viewing, since it had been assumed that people lack
suf cient free time to maintain current television viewing
levels while spending increasing amounts of free time
on the computer. That assumption, however, is evidently
false: In a recent mail survey concerning media use, a
very large majority of respondents who report increasing
time spent per week using computers report no change
in time spent watching television.
Which of the following would it be most useful to
determine in order to evaluate the argument?
(A) Whether a large majority of the survey
respondents reported watching television regularly
(B) Whether the amount of time spent watching
television is declining among people who report
that they rarely or never use computers
(C) Whether the type of television programs a person
watches tends to change as the amount of time
spent per week using computers increases
(D) Whether a large majority of the computer owners
in the survey reported spending increasing
amounts of time per week using computers
(E) Whether the survey respondents’ reports of time
spent using computers included time spent using
computers at work
580. Although the school would receive nancial bene ts if
it had soft drink vending machines in the cafeteria, we
should not allow them. Allowing soft drink machines there
would not be in our students’ interest. If our students
start drinking more soft drinks, they will be less healthy.
The argument depends on which of the following?
(A) If the soft drink vending machines were placed in
the cafeteria, students would consume more soft
drinks as a result.
(B) The amount of soft drinks that most students at
the school currently drink is not detrimental to
their health.
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(C) Students are apt to be healthier if they do not
drink soft drinks at all than if they just drink small
amounts occasionally.
(D) Students will not simply bring soft drinks from
home if the soft drink vending machines are not
placed in the cafeteria.
(E) The school’s primary concern should be to
promote good health among its students.
581. Many athletes inhale pure oxygen after exercise in an
attempt to increase muscular reabsorption of oxygen.
Measured continuously after exercise, however, the
blood lactate levels of athletes who inhale pure oxygen
are practically identical, on average, to those of athletes
who breathe normal air. The lower the blood lactate level
is, the higher the muscular reabsorption of oxygen is.
If the statements above are all true, they most strongly
support which of the following conclusions?
(A) Athletes’ muscular reabsorption of oxygen is not
increased when they inhale pure oxygen instead
of normal air.
(B) High blood lactate levels cannot be reduced.
(C) Blood lactate levels are a poor measure of
oxygen reabsorption by muscles.
(D) The amount of oxygen reabsorbed by an
athlete’s muscles always remains constant.
(E) The inhaling of pure oxygen has no legitimate
role in athletics.
582. Which of the following most logically completes the
argument?
Sviatovin is a medieval Moringian text whose author
and exact date of composition are unknown. However,
the events in the life of Prince Sviatov that the text
describes occurred in 1165, and in the diagram of
Sviatov’s family that accompanies the text his father,
who died in 1167, is identi ed as still living. Thus
Sviatovin must have been written between 1165 and
1167, assuming that ________.
(A) the life of Prince Sviatov is not the subject of any
other medieval Moringian texts
(B) the author of Sviatovin intended it to provide as
accurate a report about Prince Sviatov’s exploits
as possible
(C) the diagram accurately represents the
composition of Sviatov’s family at the time
Sviatovin was written
(D) Sviatovin is the earliest Moringian text whose
composition can be dated to within a few years
(E) Sviatovin was not written by Sviatov’s father
himself
583. A study of ticket sales at a summer theater festival
found that people who bought tickets to individual
plays had a no‐show rate of less than 1 percent,
while those who paid in advance for all ten plays
being performed that summer had a no‐show rate
of nearly 30 percent. This may be at least in part
because the greater the awareness customers retain
about the cost of an item, the more likely they are to
use it.
Which of the following would, if true, best serve as an
alternative explanation of the results of the study?
(A) The price per ticket was slightly cheaper for
those who bought all ten tickets in advance.
(B) Many people who attended the theater festival
believed strongly that they should support it
nancially.
(C) Those who attended all ten plays became eligible
for a partial refund.
(D) Usually, people who bought tickets to individual
plays did so immediately prior to each
performance that they attended.
(E) People who arrived just before the performance
began could not be assured of obtaining seats in
a preferred location.
8.4 Critical Reasoning Practice Questions
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584. Although there is no record of poet Edmund Spenser’s
parentage, we do know that as a youth Spenser
attended the Merchant Tailors’ School in London for
a period between 1560 and 1570. Records from this
time indicate that the Merchant Tailors’ Guild then had
only three members named Spenser: Robert Spenser,
listed as a gentleman; Nicholas Spenser, elected the
Guild’s Warden in 1568; and John Spenser, listed as a
“journeyman cloth‐maker.” Of these, the last was likely
the least af uent of the three—and most likely Edmund’s
father, since school accounting records list Edmund as
a scholar who attended the school at a reduced fee.
Which of the following is an assumption on which the
argument depends?
(A) Anybody in sixteenth‐century London who made
clothing professionally would have had to be a
member of the Merchant Tailors’ Guild.
(B) The fact that Edmund Spenser attended the
Merchant Tailors’ School did not necessarily
mean that he planned to become a tailor.
(C) No member of the Guild could become Guild
warden in sixteenth‐century London unless he
was a gentleman.
(D) Most of those whose fathers were members of
the Merchant Tailors’ Guild were students at the
Merchant Tailors’ School.
(E) The Merchant Tailors’ School did not reduce its fees
for the children of the more af uent Guild members.
585. Trancorp currently transports all its goods to Burland
Island by truck. The only bridge over the channel
separating Burland from the mainland is congested,
and trucks typically spend hours in traf c. Trains
can reach the channel more quickly than trucks, and
freight cars can be transported to Burland by barges
that typically cross the channel in an hour. Therefore,
to reduce shipping time, Trancorp plans to switch to
trains and barges to transport goods to Burland.
Which of the following would be most important
to know in determining whether Trancorp’s plan, if
implemented, is likely to achieve its goal?
(A) Whether transportation by train and barge
would be substantially less expensive than
transportation by truck
(B) Whether there are boats that can make the trip
between the mainland and Burland faster than
barges can
(C) Whether loading the freight cars onto barges is
very time consuming
(D) Whether the average number of vehicles
traveling over the bridge into Burland has been
relatively constant in recent years
(E) Whether most trucks transporting goods into
Burland return to the mainland empty
586. Rainwater contains hydrogen of a heavy form called
deuterium. The deuterium content of wood re ects
the deuterium content of rainwater available to trees
during their growth. Wood from trees that grew
between 16,000 and 24,000 years ago in North
America contains signi cantly more deuterium than
wood from trees growing today. But water trapped
in several North American caves that formed during
that same early period contains signi cantly less
deuterium than rainwater in North America contains
today.
Which of the following, if true, most helps to reconcile
the two ndings?
(A) There is little deuterium in the North American
caves other than the deuterium in the water
trapped there.
(B) Exposure to water after a tree has died does not
change the deuterium content of the wood.
(C) Industrialization in North America over the past
100 years has altered the deuterium content of
rain.
(D) Trees draw on shallow groundwater from rain
that falls during their growth, whereas water
trapped in caves may have fallen as rainwater
thousands of years before the caves formed.
(E) Wood with a high deuterium content is no more
likely to remain preserved for long periods than
is wood with a low deuterium content.
587. Which of the choices most logically completes the
following argument?
NowNews , although still the most popular magazine
covering cultural events in Kalopolis, has recently
suffered a signi cant drop in advertising revenue
because of falling circulation. Many readers have
begun buying a competing magazine that, at 50
cents per copy, costs less than NowNews at $1.50
per copy. In order to boost circulation and thus
increase advertising revenue, NowNews’s publisher
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521
has proposed making it available at no charge.
However, this proposal has a serious drawback,
since ________.
(A) those Kalopolis residents with the greatest
interest in cultural events are regular readers of
both magazines.
(B) one reason NowNews’s circulation fell was that
its competitor’s reporting on cultural events was
superior.
(C) the newsstands and stores that currently sell
NowNews will no longer carry it if it is being
given away for free.
(D) at present, 10 percent of the total number of copies
of each issue of NowNews are distributed free to
students on college campuses in the Kalopolis area.
(E) NowNews’s competitor would begin to lose large
amounts of money if it were forced to lower its
cover price.
588. Archaeologist: Researchers excavating a burial site
in Cyprus found a feline skeleton lying near a human
skeleton. Both skeletons were in the same sediment at
the same depth and equally well‐preserved, suggesting
that the feline and human were buried together
about 9,500 years ago. This shows that felines were
domesticated around the time farming began, when
they would have been useful in protecting stores of
grain from mice.
Which of the following, if true, would most seriously
weaken the archaeologist’s argument?
(A) Archaeologists have not found any remains of stores
of grain in the immediate vicinity of the burial site.
(B) The burial site in Cyprus is substantially older
than any other known burial site in which a feline
skeleton and a human skeleton appear to have
been buried together.
(C) Paintings found near the burial site seem to show
people keeping felines as domestic companions,
but do not show felines hunting mice.
(D) In Cyprus, there are many burial sites dating
from around 9,500 years ago in which the
remains of wild animals appear to have been
buried alongside human remains.
(E) Before felines were domesticated, early farmers
had no effective way to protect stores of grain
from mice.
589. The heavy traf c in Masana is a growing drain on the
city’s economy—the clogging of the streets of the
central business district alone cost the economy more
than $1.2 billion over the past year. In order to address
this problem, of cials plan to introduce congestion
pricing, by which drivers would pay to enter the city’s
most heavily traf cked areas during the busiest times
of the day.
Which of the following, if true, would most strongly
indicate that the plan will be a success?
(A) Approximately one- fth of the vehicles in the
central business district are in transit from one
side of the city to the other.
(B) Planners expect that, without congestion pricing,
traf c in Masana is likely to grow by 6 percent in
the next ve years.
(C) In other urban areas, congestion pricing has
strongly encouraged carpooling (sharing of rides
by private commuters).
(D) Several studies have shown that a reduction in
traf c of 15 percent in Masana could result in
5,500 or more new jobs.
(E) Over 30 percent of the vehicles in the city’s
center are occupied by more than one person.
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590. Economist: The most economically ef cient way to
reduce emissions of air pollutants is to tax them in
proportion to the damage they are likely to cause. But
in Country Y, many serious pollutants are untaxed and
unregulated, and policy makers strongly oppose new
taxes. Therefore, the best way to achieve a reduction
in air pollutant emissions in Country Y would be to
institute xed upper limits on them.
Which of the following is an assumption of the
economist’s argument?
(A) Policy makers in Country Y oppose all new taxes
equally strongly, regardless of any bene ts they
may provide.
(B) Country Y’s air pollutant emissions would not fall
signi cantly if they were taxed in proportion to
the damage they are likely to cause.
(C) Policy makers in Country Y strongly favor
reductions in air pollutant emissions.
(D) Country Y’s policy makers believe that air
pollutant emissions should be reduced with
maximum economic ef ciency.
(E) Policy makers in Country Y do not oppose
setting xed upper limits on air pollutant
emissions as strongly as they oppose new taxes.
591. Humans get Lyme disease from infected ticks. Ticks
get infected by feeding on animals with Lyme disease,
but the ease of transmission from host animal to tick
varies. With most species of host animal, transmission
of Lyme disease to ticks is extremely rare, but white‐
footed mice are an exception, readily passing Lyme
disease to ticks. And white‐footed mouse populations
greatly expand, becoming the main food source for
ticks, in areas where biodiversity is in decline.
The information in the passage most strongly supports
which of the following?
(A) In areas where many humans are infected with
Lyme disease, the proportion of ticks infected
with Lyme disease is especially high.
(B) Very few animals that live in areas where there
are no white‐footed mice are infected with Lyme
disease.
(C) Humans are less at risk of contracting Lyme
disease in areas where biodiversity is high.
(D) Ticks feed on white‐footed mice only when other
host species are not available to them.
(E) The greater the biodiversity of an area, the more
likely any given host animal in that area is to
pass Lyme disease to ticks.
592. Many industrialized nations are trying to reduce
atmospheric concentrations of carbon dioxide, a gas
released by the burning of fossil fuels. One proposal
is to replace conventional cement, which is made with
calcium carbonate, by a new “eco‐cement.” This new
cement, made with magnesium carbonate, absorbs
large amounts of carbon dioxide when exposed to the
atmosphere. Therefore, using eco‐cement for new
concrete building projects will signi cantly help reduce
atmospheric concentrations of carbon dioxide.
Which of the following, if true, most strengthens the
argument?
(A) The cost of magnesium carbonate, currently
greater than the cost of calcium carbonate,
probably will fall as more magnesium carbonate
is used in cement manufacture.
(B) Eco‐cement is strengthened when absorbed
carbon dioxide reacts with the cement.
(C) Before the development of eco‐cement,
magnesium‐based cement was considered too
susceptible to water erosion to be of practical use.
(D) The manufacture of eco‐cement uses considerably
less fossil fuel per unit of cement than the
manufacture of conventional cement does.
(E) Most building‐industry groups are unaware of the
development or availability of eco‐cement.
593. Which of the following most logically completes the
argument below?
Davison River farmers are currently deciding between
planting winter wheat this fall or spring wheat next
spring. Winter wheat and spring wheat are usually
about equally pro table. Because of new government
restrictions on the use of Davison River water for
irrigation, per acre yields for winter wheat, though not
for spring wheat, would be much lower than average.
Therefore, planting spring wheat will be more pro table
than planting winter wheat, since ________.
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(A) the smaller‐than‐average size of a winter wheat
harvest this year would not be compensated for
by higher winter wheat prices
(B) new crops of spring wheat must be planted
earlier than the time at which standing crops of
winter wheat are ready to be harvested
(C) the spring wheat that farmers in the Davison River
region plant is well adapted to the soil of the region
(D) spring wheat has uses that are different from
those of winter wheat
(E) planting spring wheat is more pro table than
planting certain other crops, such as rye
594. Advertisement: When your car’s engine is running at
its normal operating temperature, any major brand
of motor oil will protect it about as well as Tuff does.
When the engine is cold, it is a different story: Tuff
motor oil ows better at lower temperatures than its
major competitors do. So, if you want your car’s engine
to have maximum protection, you should use Tuff.
Which of the following, if true, most strengthens the
argument in the advertisement?
(A) Tuff motor oil provides above‐average protection
for engines that happen to overheat.
(B) Tuff motor oil is periodically supplied free of
charge to automobile manufacturers to use in
factory‐new cars.
(C) Tuff motor oil’s share of the engine oil market
peaked three years ago.
(D) Tuff motor oil, like any motor oil, is thicker and
ows less freely at cold temperatures than at hot
temperatures.
(E) Tuff motor oil is manufactured at only one
re nery and shipped from there to all markets.
595. The Testament of William Thorpe was published around
1530 as an appendix to Thorpe’s longer Examination .
Many scholars, however, doubt the attribution of
the Testament to Thorpe because, whereas the
Examination is dated 1406, the Testament is dated
1460. One scholar has recently argued that the 1460
date be amended to 1409, based on the observation
that when these numbers are expressed as Roman
numerals, MCCCCLX and MCCCCIX, it becomes easy
to see how the dates might have become confused
through scribal error.
Which of the following, if true, would most support
the scholar’s hypothesis concerning the date of the
Testament ?
(A) The sole evidence that historians have had that
William Thorpe died no earlier than 1460 was the
presumed date of publication of the Testament .
(B) In the preface to the 1530 publication, the editor
attributes both works to William Thorpe.
(C) Few writers in fteenth‐century England
marked dates in their works using only Roman
numerals.
(D) The Testament alludes to a date, “Friday,
September 20,” as apparently contemporaneous
with the writing of the Testament , and September
20 fell on a Friday in 1409 but not in 1460.
(E) The Testament contains few references to
historical events that occurred later than 1406.
596. To reduce productivity losses from employees calling
in sick, Corporation X implemented a new policy
requiring employees to come into work unless they
were so sick that they had to go to a doctor. But a
year after the policy was implemented, a study found
that Corporation X’s overall productivity losses due to
reported employee illnesses had increased.
Which of the following, if true, would best explain why
the policy produced the reverse of its intended effect?
(A) After the policy was implemented, employees
more frequently went to the doctor when they
felt sick.
(B) Before the policy was implemented, employees
who were not sick at all often called in sick.
(C) Employees coming into work when sick often
infect many of their coworkers.
(D) Unusually few employees became genuinely
sick during the year after the policy was
implemented.
(E) There are many other factors besides employee
illness that can adversely affect productivity.
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597. Advertising by mail has become much less effective,
with fewer consumers responding. Because
consumers are increasingly overwhelmed by the sheer
amount of junk mail they receive, most discard almost
all offers without considering them. Thus, an effective
way for corporations to improve response rates would
be to more carefully target the individuals to whom
they mail advertising, thereby cutting down on the
amount of junk mail each consumer receives.
Which of the following, if true, would most support the
recommendation above?
(A) There are cost‐effective means by which
corporations that currently advertise by mail
could improve response rates.
(B) Many successful corporations are already
carefully targeting the individuals to whom they
mail advertising.
(C) Any consumer who, immediately after receiving
an advertisement by mail, merely glances at it, is
very likely to discard it.
(D) Improvements in the quality of the advertising
materials used in mail that is carefully targeted
to individuals can improve the response rate for
such mail.
(E) Response rates to carefully targeted advertisements
by mail are considerably higher, on average, than
response rates to most other forms of advertising.
598. Petrochemical industry officials have said that
the extreme pressure exerted on plant managers
during the last five years to improve profits by
cutting costs has done nothing to impair the
industry’s ability to operate safely. However,
environmentalists contend that the recent rash of
serious oil spills and accidents at petrochemical
plants is traceable to cost‐cutting measures.
Which of the following, if true, would provide the
strongest support for the position held by industry
of cials?
(A) The petrochemical industry bene ts if accidents do
not occur, since accidents involve risk of employee
injury as well as loss of equipment and product.
(B) Petrochemical industry unions recently
demanded that additional money be spent on
safety and environmental protection measures,
but the unions readily abandoned those demands
in exchange for job security.
(C) Despite major cutbacks in most other areas
of operation, the petrochemical industry has
devoted more of its resources to environmental
and safety measures in the last ve years than in
the preceding ve years.
(D) There is evidence that the most damaging of the
recent oil spills would have been prevented had
cost‐cutting measures not been instituted.
(E) Both the large nes and the adverse publicity
generated by the most recent oil spill have
prompted the petrochemical industry to increase
the resources devoted to oil‐spill prevention.
599. Economist: The price of tap water in our region should
be raised drastically. Supplies in local freshwater
reservoirs have been declining for years because
water is being used faster than it can be replenished.
Since the price of tap water has been low, few users
have bothered to adopt even easy conservation
measures.
The two sections in boldface play which of the
following roles in the economist’s argument?
(A) The rst is a conclusion for which support is
provided, and which in turn supports the main
conclusion; the second is the main conclusion.
(B) The rst is an observation for which the second
provides an explanation; the second is the main
conclusion but not the only conclusion.
(C) The rst is a premise supporting the argument’s
main conclusion; so is the second.
(D) The rst is the only conclusion; the second
provides an explanation for the rst.
(E) The rst is the main conclusion; the second is
a conclusion for which support is provided, and
which in turn supports the rst.
600. Politician: Hybrid cars use signi cantly less fuel
per kilometer than nonhybrids. And fuel produces
air pollution, which contributes to a number of
environmental problems. Motorists can save money by
driving cars that are more fuel ef cient, and they will
be encouraged to drive hybrid cars if we make them
aware of that fact. Therefore, we can help reduce the
total amount of pollution emitted by cars in this country
by highlighting this advantage of hybrid cars.
Which of the following, if true, would most indicate a
vulnerability of the politician’s argument?
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(A) People with more fuel‐ef cient cars typically drive
more than do those with less fuel‐ef cient cars.
(B) Not all air pollution originates from automobiles.
(C) Hybrid cars have already begun to gain popularity.
(D) Fuel‐ef cient alternatives to hybrid cars will likely
become available in the future.
(E) The future cost of gasoline and other fuel
cannot be predicted with absolute precision or
certainty.
601. Which of the following most logically completes the
passage?
A recent government study links the high rates
of respiratory ailments in Groverston to airborne
pollutants released by the Woodco plywood
manufacturing plant there. To address the problem, the
government imposed strict regulations on emissions
which will go into effect in four years.
Although Woodco plans to cut its emissions in half two
years ahead of schedule, it is unlikely that the rate of
respiratory ailments will decline before the regulations
go into effect, since ________.
(A) the number of facilities capable of treating
respiratory ailments is not likely to increase
(B) reducing emissions even further than planned
would necessitate decreasing production at
Woodco
(C) it is dif cult to make accurate, long‐term
predictions about emissions
(D) not all respiratory ailments are caused by
airborne pollutants
(E) three new plywood manufacturing plants are
about to go into production in Groverston
602. One summer, oods covered low‐lying garlic elds
situated in a region with a large mosquito population.
Since mosquitoes lay their eggs in standing water,
ooded elds would normally attract mosquitoes, yet
no mosquitoes were found in the elds. Diallyl sul de,
a major component of garlic, is known to repel several
species of insects, including mosquitoes, so it is
likely that diallyl sul de from the garlic repelled the
mosquitoes.
Which of the following, if true, most strengthens the
argument?
(A) Diallyl sul de is also found in onions but at
concentrations lower than in garlic.
(B) The mosquito population of the region as a
whole was signi cantly smaller during the year in
which the ooding took place than it had been in
previous years.
(C) By the end of the summer, most of the garlic
plants in the ooded elds had been killed by
waterborne fungi.
(D) Many insect species not repelled by diallyl sul de
were found in the ooded garlic elds throughout
the summer.
(E) Mosquitoes are known to be susceptible to
toxins in plants other than garlic, such as
marigolds.
603. Which of the following most logically completes the
passage?
Pecan growers get a high price for their crop when
pecans are comparatively scarce, but the price drops
sharply when pecans are abundant. Thus, in high‐yield
years, growers often hold back part of their crop in
refrigerated warehouses for one or two years, hoping
for higher prices in the future. This year’s pecan crop
was the smallest in ve years. It is nonetheless quite
possible that a portion of this year’s crop will be held
back, since ________.
(A) each of the last two years produced
recordbreaking pecan yields
(B) the quality of this year’s pecan crop is no worse
than the quality of the pecan crops of the
previous ve years
(C) pecan prices have not been subject to sharp
uctuations in recent years
(D) for some pecan growers, this year’s crop was no
smaller than last year’s
(E) the practice of holding back part of one year’s
crop had not yet become widespread the last time
the pecan crop was as small as it was this year
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604. Coffee shop owner: A large number of customers will
pay at least the fair market value for a cup of coffee,
even if there is no formal charge. Some will pay more
than this out of appreciation of the trust that is placed
in them. And our total number of customers is likely to
increase. We could therefore improve our net cash ow
by implementing an honor system in which customers pay
what they wish for coffee by depositing money in a can.
Manager: We’re likely to lose money on this plan. Many
customers would cheat the system, paying a very
small sum or nothing at all.
Which of the following, if true, would best support the
owner’s plan, in light of the manager’s concern?
(A) The new system, if implemented, would increase
the number of customers.
(B) By roasting its own coffee, the shop has
managed to reduce the dif culties (and cost)
of maintaining an inventory of freshly roasted
coffee.
(C) Many customers stay in the cafe for long
stretches of time.
(D) The shop makes a substantial pro t from pastries
and other food bought by the coffee drinkers.
(E) No other coffee shop in the area has such a system.
605. Which of the following most logically completes the
argument?
By competing with rodents for seeds, black ants help
control rodent populations that pose a public health
risk. However, a very aggressive species of black ant,
the Loma ant, which has recently invaded a certain
region, has a venomous sting that is often fatal to
humans. Therefore, the planned introduction into that
region of ant ies, which prey on Loma ants, would
bene t public health, since ________.
(A) ant ies do not attack black ants other than
Loma ants
(B) Loma ants are less effective than many bird
species in competing with rodents for seeds
(C) certain other species of black ants are more
effective than Loma ants in competing with
rodents for seeds
(D) the sting of Loma ants can also be fatal to rodents
(E) some pesticides that could be used to control
Loma ants are harmful to the environment
606. Journalist: In physics journals, the number of articles
reporting the results of experiments involving particle
accelerators was lower last year than it had been in
previous years. Several of the particle accelerators
at major research institutions were out of service the
year before last for repairs, so it is likely that the low
number of articles was due to the decline in availability
of particle accelerators.
Which of the following, if true, most seriously
undermines the journalist’s argument?
(A) Every article based on experiments with particle
accelerators that was submitted for publication
last year actually was published.
(B) The average time scientists must wait for access
to a particle accelerator has declined over the
last several years.
(C) The number of physics journals was the same
last year as in previous years.
(D) Particle accelerators can be used for more than
one group of experiments in any given year.
(E) Recent changes in the editorial policies of several
physics journals have decreased the likelihood
that articles concerning particle‐accelerator
research will be accepted for publication.
607. Birds have been said to be descended from certain
birdlike dinosaur species with which they share
distinctive structural features. The fossil record,
however, shows that this cannot be so, since there
are bird fossils that are much older than the earliest
birdlike dinosaur fossils that have been found.
Which of the following is an assumption on which the
argument relies?
(A) The birdlike dinosaurs have no living descendants.
(B) There are no ightless dinosaur species that
have the distinctive structural features shared by
birds and birdlike dinosaurs.
(C) There are no birdlike dinosaur fossils that are
older than the bird fossils but have not yet been
unearthed.
(D) It could not have been the case that some
birds were descended from one of the birdlike
dinosaur species and other birds from another.
(E) Birds cannot have been descended from
dinosaur species with which the birds do not
share the distinctive structural features.
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608. City council member: Demand for electricity has been
increasing by 1.5 percent a year, and there simply
is no more space to build additional power plants to
meet future demand increases. We must therefore
begin to curtail usage, which is why I propose passing
ordinances requiring energy‐conservation measures in
all city departments.
The city council member’s proposal assumes which of
the following?
(A) Existing power plants do not have the capacity
to handle all of the projected increase in demand
for electricity.
(B) No city departments have implemented energy‐
conservation measures voluntarily.
(C) Passing ordinances designed to curtail
electricity usage will not have negative economic
consequences for the city.
(D) Residential consumers are not responsible for
the recent increases in demand for electricity.
(E) City departments that successfully conserve
energy will set a good example for residential
and industrial consumers of electricity.
609. Which of the following most logically completes the
argument below?
Using broad‐spectrum weed killers on weeds that are
competing with crops for sunlight, water, and nutrients
presents a dif culty: how to keep the crop from being
killed along with the weeds. For at least some food
crops, specially treated seed that produces plants
resistant to weed killers is under development. This
resistance wears off as the plants mature. Therefore,
the special seed treatment will be especially useful for
plants that ________.
(A) produce their crop over an extended period of
time, as summer squash does
(B) produce large seeds that are easy to treat
individually, as corn and beans do
(C) provide, as they approach maturity, shade dense
enough to keep weeds from growing
(D) are typically grown in large tracts devoted to a
single crop
(E) are cultivated speci cally for the seed they
produce rather than for their leaves or roots
610. Previously, Autoco designed all of its cars itself and
then contracted with specialized parts suppliers to
build parts according to its speci cations. Now it plans
to include its suppliers in designing the parts they
are to build. Since many parts suppliers have more
designers with specialized experience than Autoco
has, Autoco expects this shift to reduce the overall
time and cost of the design of its next new car.
Which of the following, if true, most strongly supports
Autoco’s expectation?
(A) When suppliers provide their own designs,
Autoco often needs to modify its overall design.
(B) In order to provide designs for Autoco, several
of the parts suppliers will have to add to their
existing staffs of designers.
(C) Parts and services provided by outside suppliers
account for more than 50 percent of Autoco’s
total costs.
(D) When suppliers built parts according to
speci cations provided by Autoco, the suppliers
competed to win contracts.
(E) Most of Autoco’s suppliers have on hand a wide
range of previously prepared parts designs that
can readily be modi ed for a new car.
8.4 Critical Reasoning Practice Questions
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611. In Stenland, many workers have been complaining
that they cannot survive on minimum wage, the
lowest wage an employer is permitted to pay. The
government is proposing to raise the minimum wage.
Many employers who pay their workers the current
minimum wage argue that if it is raised, unemployment
will increase because they will no longer be able to
afford to employ as many workers.
Which of the following, if true in Stenland, most strongly
supports the claim that raising the minimum wage there
will not have the effects that the employers predict?
(A) For any position with wages below a living wage,
the dif culty of nding and retaining employees
adds as much to employment costs as would
raising wages.
(B) Raising the minimum wage does not also
increase the amount employers have to
contribute in employee bene ts.
(C) When in ation is taken into account, the
proposed new minimum wage is not as high as
the current one was when it was introduced.
(D) Many employees currently being paid wages at
the level of the proposed new minimum wage will
demand signi cant wage increases.
(E) Many employers who pay some workers only the
minimum wage also pay other workers wages
that are much higher than the minimum.
612. Which of the following most logically completes the
argument?
The attribution of the choral work Lacrimae to the
composer Pescard (1400–1474) has been regarded
as tentative, since it was based on a single treatise
from the early 1500s that named Pescard as the
composer. Recently, several musical treatises from
the late 1500s have come to light, all of which
name Pescard as the composer of Lacrimae .
Unfortunately, these newly discovered treatises lend
no support to the attribution of Lacrimae to Pescard,
since ________.
(A) the treatise from the early 1500s misidenti es
the composers of some of the musical works it
considers
(B) the author of the treatise from the early 1500s
had no very strong evidence on which to base
the identi cation of Pescard as the composer of
Lacrimae
(C) there are works that can conclusively be
attributed to Pescard that are not even
mentioned in the treatise from the early 1500s
(D) the later treatises probably had no source for
their attribution other than the earlier treatise
(E) no known treatises from the 1600s identify
Pescard as the composer of Lacrimae
613. When trying to identify new technologies that promise to
transform the marketplace, market researchers survey
the managers of those companies that are developing
new technologies. Such managers have an enormous
stake in succeeding, so they invariably overstate
the potential of their new technologies. Surprisingly,
however, market researchers typically do not survey
a new technology’s potential buyers, even though it
is the buyers—not the producers—who will ultimately
determine a technology’s commercial success.
Which of the following, if true, best accounts for the
typical survey practices among market researchers?
(A) If a new technology succeeds, the commercial
bene ts accrue largely to the producers, not to
the buyers, of that technology.
(B) People who promote the virtues of a new
technology typically fail to consider that the old
technology that is currently in use continues to
be improved, often substantially.
(C) Investors are unlikely to invest substantial amounts
of capital in a company whose own managers are
skeptical about the commercial prospects of a
new technology they are developing.
(D) The potential buyers for not‐yet‐available
technologies can seldom be reliably identi ed.
(E) The developers of a new technology are
generally no better positioned than its potential
buyers to gauge how rapidly the new technology
can be ef ciently mass‐produced.
614. Infotek, a computer manufacturer in Katrovia, has just
introduced a new personal computer model that sells
for signi cantly less than any other model. Market
research shows, however, that very few Katrovian
households without personal computers would buy
a computer, regardless of its price. Therefore,
introducing the new model is unlikely to increase the
number of computers in Katrovian homes.
Which of the following is an assumption on which the
argument depends?
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(A) Infotek achieved the lower price of the new
model by using components of lower quality than
those used by other manufacturers.
(B) The main reason cited by consumers in Katrovia
for replacing a personal computer is the desire
to have an improved model.
(C) Katrovians in households that already have
computers are unlikely to purchase the new
Infotek model as an additional computer for
home use.
(D) The price of other personal computers in
Katrovia is unlikely to drop below the price of
Infotek’s new model in the near future.
(E) Most personal computers purchased in Katrovia
are intended for home use.
615. Fast‐food restaurants make up 45 percent of all
restaurants in Canatria. Customers at these restaurants
tend to be young; in fact, studies have shown that
the older people get, the less likely they are to eat in
fast‐food restaurants. Since the average age of the
Canatrian population is gradually rising and will continue
to do so, the number of fast‐food restaurants is likely to
decrease.
Which of the following, if true, most seriously weakens
the argument?
(A) Fast‐food restaurants in Canatria are getting
bigger, so each one can serve more customers.
(B) Some older people eat at fast‐food restaurants
more frequently than the average young person.
(C) Many people who rarely eat in fast‐food restaurants
nevertheless eat regularly in restaurants.
(D) The overall population of Canatria is growing
steadily.
(E) As the population of Canatria gets older, more
people are eating at home.
616. In order to withstand tidal currents, juvenile horseshoe
crabs frequently burrow in the sand. Such burrowing
discourages barnacles from clinging to their shells.
When fully grown, however, the crabs can readily
withstand tidal currents without burrowing, and thus
they acquire substantial populations of barnacles.
Surprisingly, in areas where tidal currents are very
weak, juvenile horseshoe crabs are found not to have
signi cant barnacle populations, even though they
seldom burrow.
Which of the following, if true, most helps to explain
the surprising nding?
(A) Tidal currents do not themselves dislodge
barnacles from the shells of horseshoe crabs.
(B) Barnacles most readily attach themselves to
horseshoe crabs in areas where tidal currents
are weakest.
(C) The strength of the tidal currents in a given
location varies widely over the course of a day.
(D) A very large barnacle population can signi cantly
decrease the ability of a horseshoe crab to nd food.
(E) Until they are fully grown, horseshoe crabs shed
their shells and grow new ones several times a
year.
617. Last year a chain of fast‐food restaurants, whose
menu had always centered on hamburgers, added its
rst vegetarian sandwich, much lower in fat than the
chain’s other offerings. Despite heavy marketing, the
new sandwich accounts for a very small proportion of
the chain’s sales. The sandwich’s sales would have to
quadruple to cover the costs associated with including it
on the menu. Since such an increase is unlikely, the chain
would be more pro table if it dropped the sandwich.
Which of the following, if true, most seriously weakens
the argument?
(A) Although many of the chain’s customers have
never tried the vegetarian sandwich, in a market
research survey most of those who had tried it
reported that they were very satis ed with it.
(B) Many of the people who eat at the chain’s
restaurants also eat at the restaurants of
competing chains and report no strong
preference among the competitors.
(C) Among fast‐food chains in general, there has
been little or no growth in hamburger sales over
the past several years as the range of competing
offerings at other restaurants has grown.
(D) When even one member of a group of diners is a
vegetarian or has a preference for low‐fat food,
the group tends to avoid restaurants that lack
vegetarian or low‐fat menu options.
(E) An attempt by the chain to introduce a lower‐fat
hamburger failed several years ago, since it
attracted few new customers and most of the
chain’s regular customers greatly preferred the
taste of the regular hamburgers.
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618. Transportation expenses accounted for a large portion
of the total dollar amount spent on trips for pleasure by
residents of the United States in 1997, and about half
of the total dollar amount spent on transportation was
for airfare. However, the large majority of United States
residents who took trips for pleasure in 1997 did not
travel by airplane but used other means of transportation.
If the statements above are true, which of the following
must also be true about United States residents who
took trips for pleasure in 1997?
(A) Most of those who traveled by airplane did so
because the airfare to their destination was
lower than the cost of other available means of
transportation.
(B) Most of those who traveled by airplane did so
because other means of transportation to their
destination were unavailable.
(C) Per mile traveled, those who traveled by airplane
tended to spend more on transportation to their
destination than did those who used other means
of transportation.
(D) Overall, people who did not travel by airplane
had lower average transportation expenses than
people who did.
(E) Those who traveled by airplane spent about
as much, on average, on other means of
transportation as they did on airfare.
619. Voters commonly condemn politicians for being
insincere, but politicians often must disguise their
true feelings when they make public statements. If
they expressed their honest views—about, say, their
party’s policies—then achieving politically necessary
compromises would be much more dif cult. Clearly,
the very insincerity that people decry shows that our
government is functioning well.
Which of the following, if true, most seriously
undermines this reasoning?
(A) Achieving political compromises is not all that
is necessary for the proper functioning of a
government.
(B) Some political compromises are not in the best
long‐term interest of the government.
(C) Voters often judge politicians by criteria other than
the sincerity with which they express their views.
(D) A political party’s policies could turn out to be
detrimental to the functioning of a government.
(E) Some of the public statements made by
politicians about their party’s policies could in
fact be sincere.
620. To reduce waste of raw materials, the government of
Sperland is considering requiring household appliances
to be broken down for salvage when discarded. To
cover the cost of salvage, the government is planning
to charge a fee, which would be imposed when the
appliance is rst sold. Imposing the fee at the time of
salvage would reduce waste more effectively, however,
because consumers tend to keep old appliances
longer if they are faced with a fee for discarding them.
Which of the following, if true, most seriously weakens
the argument?
(A) Increasing the cost of disposing of an appliance
properly increases the incentive to dispose of it
improperly.
(B) The fee provides manufacturers with no incentive
to produce appliances that are more durable.
(C) For people who have bought new appliances
recently, the salvage fee would not need to be
paid for a number of years.
(D) People who sell their used, working appliances
to others would not need to pay the salvage fee.
(E) Many nonfunctioning appliances that are
currently discarded could be repaired at
relatively little expense.
621. When there is less rainfall than normal, the water
level of Australian rivers falls and the rivers ow more
slowly. Because algae whose habitat is river water
grow best in slow‐moving water, the amount of algae
per unit of water generally increases when there has
been little rain. By contrast, however, following a
period of extreme drought, algae levels are low even in
very slow‐moving river water.
Which of the following, if true, does most to explain the
contrast described above?
(A) During periods of extreme drought, the
populations of some of the species that feed on
algae tend to fall.
(B) The more slowly water moves, the more conducive
its temperature is to the growth of algae.
(C) When algae populations reach very high levels,
conditions within the river can become toxic for
some of the other species that normally live there.
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(D) Australian rivers dry up completely for short
intervals in periods of extreme drought.
(E) Except during periods of extreme drought, algae
levels tend to be higher in rivers in which the ow
has been controlled by damming than in rivers
that ow freely.
622. Increased use of incineration is sometimes advocated
as a safe way to dispose of chemical waste. But
opponents of incineration point to the 40 incidents
involving unexpected releases of dangerous chemical
agents that were reported just last year at two existing
incinerators commissioned to destroy a quantity of
chemical waste material. Since designs for proposed
new incinerators include no additional means of
preventing such releases, leaks will only become more
prevalent if use of incineration increases.
Which of the following, if true, most seriously weakens
the argument?
(A) At the two incinerators at which leaks were
reported, staff had had only cursory training on the
proper procedures for incinerating chemical waste.
(B) Other means of disposing of chemical waste,
such as chemical neutralization processes, have
not been proven safer than incineration.
(C) The capacity of existing incinerators is suf cient
to allow for increased incineration of chemical
waste without any need for new incinerators.
(D) The frequency of reports of unexpected releases
of chemical agents at newly built incinerators
is about the same as the frequency at older
incinerators.
(E) In only three of the reported incidents of
unexpected chemical leaks did the releases
extend outside the property on which the
incinerators were located.
623. Public health expert: Increasing the urgency of a
public health message may be counterproductive.
In addition to irritating the majority who already behave
responsibly, it may undermine all government
pronouncements on health by convincing people
that such messages are overly cautious. And there
is no reason to believe that those who ignore measured
voices will listen to shouting.
The two sections in boldface play which of the
following roles in the public health expert’s argument?
(A) The rst is a conclusion for which support
is provided, but is not the argument’s main
conclusion; the second is an unsupported premise
supporting the argument’s main conclusion.
(B) The rst is a premise supporting the only explicit
conclusion; so is the second.
(C) The rst is the argument’s main conclusion; the
second supports that conclusion and is itself a
conclusion for which support is provided.
(D) The rst is a premise supporting the argument’s
only conclusion; the second is that conclusion.
(E) The rst is the argument’s only explicit conclusion;
the second is a premise supporting that conclusion.
624. Several industries have recently switched at least
partly from older technologies powered by fossil fuels
to new technologies powered by electricity. It is thus
evident that less fossil fuel is being used as a result
of the operations of these industries than would have
been used if these industries had retained their older
technologies.
Which of the following, if true, most strengthens the
argument above?
(A) Many of the industries that have switched
at least partly to the new technologies have
increased their output.
(B) Less fossil fuel was used to manufacture the
machinery employed in the new technologies
than was originally used to manufacture the
machinery employed in the older technologies.
(C) More electricity is used by those industries that have
switched at least partly to the new technologies than
by those industries that have not switched.
(D) Some of the industries that have switched at least
partly to the new technologies still use primarily
technologies that are powered by fossil fuels.
(E) The amount of fossil fuel used to generate the
electricity needed to power the new technologies
is less than the amount that would have been
used to power the older technologies.
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625. The difference in average annual income in favor of
employees who have college degrees, compared with
those who do not have such degrees, doubled between
1980 and 1990. Some analysts have hypothesized
that increased competition between employers for
employees with college degrees drove up income for
such employees.
Which of the following, if true, most seriously
undermines the explanation described above?
(A) During the 1980s a growing percentage of
college graduates, unable to nd jobs requiring a
college degree, took unskilled jobs.
(B) The average age of all employees increased
slightly during the 1980s.
(C) The unemployment rate changed very little
throughout most of the 1980s.
(D) From 1980 to 1990 the difference in average
income between employees with advanced
degrees and those with bachelor’s degrees also
increased.
(E) During the 1980s there were some employees
with no college degree who earned incomes
comparable to the top incomes earned by
employees with a college degree.
626. Which of the following most logically completes the
passage?
According to the last pre-election poll in
Whippleton, most voters believe that the three
problems government needs to address, in
order of importance, are pollution, crime, and
unemployment. Yet in the election, candidates from
parties perceived as strongly against pollution were
defeated, while those elected were all from parties
with a history of opposing legislation designed to
reduce pollution. These results should not be taken
to indicate that the poll was inaccurate, however,
since __________.
(A) some voters in Whippleton do not believe that
pollution needs to be reduced
(B) every candidate who was defeated had a strong
antipollution record
(C) there were no issues other than crime,
unemployment, and pollution on which the
candidates had signi cant differences of opinion
(D) all the candidates who were elected were
perceived as being stronger against both crime
and unemployment than the candidates who
were defeated
(E) many of the people who voted in the election
refused to participate in the poll
627. Manufacturing plants in Arundia have recently been
acquired in substantial numbers by investors from
abroad. Arundian politicians are proposing legislative
action to stop such investment, justifying the proposal
by arguing that foreign investors, opportunistically
exploiting a recent fall in the value of the Arundian
currency, were able to buy Arundian assets at less than
their true value.
Which of the following, if true, casts the most serious
doubt on the adequacy of the Arundian politicians’
justi cation for the proposed legislation?
(A) The Arundian government originally welcomed
the fall in the value of the Arundian currency
because the fall made Arundian exports more
competitive on international markets.
(B) Foreign investors who acquired Arundian
manufacturing plants generally did so with no
intention of keeping and running those plants
over the long term.
(C) Without the recent fall in the value of the
Arundian currency, many of the Arundian assets
bought by foreign investors would have been
beyond the nancial reach of those investors.
(D) In Concordia, a country broadly similar to
Arundia, the share of manufacturing assets that
is foreign-controlled is 60 percent higher than it
is in Arundia.
(E) The true value of an investment is determined by
the value of the pro ts from it, and the low value
of the Arundian currency has depressed the
value of any pro ts earned by foreign investors
from Arundian assets.
628. Proposed new safety rules for Beach City airport would
lengthen considerably the minimum time between
takeoffs from the airport. In consequence, the airport
would be able to accommodate 10 percent fewer
ights than currently use the airport daily. The city’s
operating budget depends heavily on taxes generated
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by tourist spending, and most of the tourists come
by plane. Therefore, the proposed new safety rules,
if adopted, will reduce the revenue available for the
operating budget.
The argument depends on assuming which of the
following?
(A) There are no periods of the day during which
the interval between ights taking off from the
airport is signi cantly greater than the currently
allowed minimum.
(B) Few, if any, of the tourists who use Beach City
airport do so when their main destination is a
neighboring community and not Beach City itself.
(C) If the proposed safety rules are adopted, the
reduction in tourist numbers will not result mainly
from a reduction in the number of tourists who
spend relatively little in Beach City.
(D) Increasing the minimum time between takeoffs
is the only way to achieve necessary safety
improvements without a large expenditure by the
city government on airport enhancements.
(E) The response to the adoption of the new safety
rules would not include a large increase in the
number of passengers per ight.
629. The introduction of new drugs into the market is
frequently prevented by a shortage of human subjects
for the clinical trials needed to show that the drugs are
safe and effective. Since the lives and health of people
in future generations may depend on treatments that
are currently experimental, practicing physicians are
morally in the wrong when, in the absence of any
treatment proven to be effective, they fail to encourage
suitable patients to volunteer for clinical trials.
Which of the following, if true, casts most doubt on the
conclusion of the argument?
(A) Many drugs undergoing clinical trials are
intended for the treatment of conditions for
which there is currently no effective treatment.
(B) Patients do not share the physician’s professional
concern for public health, but everyone has a
moral obligation to alleviate suffering when able
to do so.
(C) Usually, half the patients in a clinical trial serve
as a control group and receive a nonactive drug
in place of the drug being tested.
(D) An experimental drug cannot legally be made
available to patients unless those patients are
subjects in clinical trials of the drug.
(E) Physicians have an overriding moral and legal
duty to care for the health and safety of their
current patients.
630. As a construction material, bamboo is as strong as
steel and sturdier than concrete. Moreover, in tropical
areas bamboo is a much less expensive construction
material than either steel or concrete and is always
readily available. In tropical areas, therefore, building with
bamboo makes better economic sense than building with
steel or concrete, except where land values are high.
Which of the following, if true, most helps to explain
the exception noted above?
(A) Buildings constructed of bamboo are less likely
to suffer earthquake damage than are steel and
concrete buildings.
(B) Bamboo is unsuitable as a building material for
multistory buildings.
(C) In order to protect it from being damaged by
termites and beetles, bamboo must be soaked,
at some expense, in a preservative.
(D) In some tropical areas, bamboo is used to
make the scaffolding that is used during large
construction projects.
(E) Bamboo growing in an area where land values
are increasing is often cleared to make way for
construction.
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631. Newspaper editors should not allow reporters to write
the headlines for their own stories. The reason for this
is that, while the headlines that reporters themselves
write are often clever, what typically makes them
clever is that they allude to little-known information
that is familiar to the reporter but that never appears
explicitly in the story itself.
Which of the following, if true, most strengthens the
argument?
(A) The reporter who writes a story is usually better
placed than the reporter’s editor is to judge what
the story’s most newsworthy features are.
(B) To write a headline that is clever, a person must
have suf cient understanding of the story that
the headline accompanies.
(C) Most reporters rarely bother to nd out how
other reporters have written stories and
headlines about the same events that they
themselves have covered.
(D) For virtually any story that a reporter writes,
there are at least a few people who know more
about the story’s subject matter than does the
reporter.
(E) The kind of headlines that newspaper editors want
are those that anyone who has read a reporter’s
story in its entirety will recognize as clever.
632. Scientists have modi ed feed corn genetically,
increasing its resistance to insect pests. Farmers
who tried out the genetically modi ed corn last
season applied less insecticide to their corn elds
and still got yields comparable to those they would
have gotten with ordinary corn. Ordinary corn seed,
however, costs less, and what these farmers saved
on insecticide rarely exceeded their extra costs
for seed. Therefore, for most feed‐corn farmers,
switching to genetically modi ed seed would be
unlikely to increase pro ts.
Which of the following would it be most useful to know
in order to evaluate the argument?
(A) Whether there are insect pests that sometimes
reduce feed‐corn yields, but against which
commonly used insecticides and the genetic
modi cation are equally ineffective
(B) Whether the price that farmers receive for feed
corn has remained steady over the past few
years
(C) Whether the insecticides typically used on feed
corn tend to be more expensive than insecticides
typically used on other crops
(D) Whether most of the farmers who tried the
genetically modi ed corn last season applied
more insecticide than was actually necessary
(E) Whether, for most farmers who plant feed corn,
it is their most pro table crop
633. Debater: The average amount of overtime per month
worked by an employee in the manufacturing division
of the Haglut Corporation is 14 hours. Most employees
of the Haglut Corporation work in the manufacturing
division. Furthermore, the average amount of overtime
per month worked by any employee in the company
generally does not uctuate much from month to
month. Therefore, each month, most employees of the
Haglut Corporation almost certainly work at least some
overtime.
The debater’s argument is most vulnerable to criticism
on which of these grounds?
(A) It takes for granted that the manufacturing
division is a typical division of the corporation
with regard to the average amount of overtime
its employees work each month.
(B) It takes for granted that if a certain average
amount of overtime is worked each month by
each employee of the Haglut Corporation, then
approximately the same amount of overtime
must be worked each month by each employee
of the manufacturing division.
(C) It confuses a claim from which the argument’s
conclusion about the Haglut Corporation would
necessarily follow with a claim that would follow
from the argument’s conclusion only with a high
degree of probability.
(D) It overlooks the possibility that even if, on
average, a certain amount of overtime is worked
by the members of some group, many members
of that group may work no overtime at all.
(E) It overlooks the possibility that even if most
employees of the corporation work some
overtime each month, any one corporate
employee may, in some months, work no
overtime.
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634. Proponents of the recently introduced tax on sales
of new luxury boats had argued that a tax of this sort
would be an equitable way to increase government
revenue because the admittedly heavy tax burden
would fall only on wealthy people and neither they nor
anyone else would suffer any economic hardship. In
fact, however, 20 percent of the workers employed by
manufacturers of luxury boats have lost their jobs as a
direct result of this tax.
The information given, if true, most strongly supports
which of the following?
(A) The market for luxury boats would have
collapsed even if the new tax on luxury boats had
been lower.
(B) The new tax would produce a net gain in tax
revenue for the government only if the yearly
total revenue that it generates exceeds the total
of any yearly tax-revenue decrease resulting from
the workers’ loss of jobs.
(C) Because many people never buy luxury items,
imposing a sales tax on luxury items is the kind
of legislative action that does not cost incumbent
legislators much popular support.
(D) Before the tax was instituted, luxury boats were
largely bought by people who were not wealthy.
(E) Taxes can be equitable only if their burden is
evenly distributed over the entire population.
635. In Wareland last year, 16 percent of licensed drivers
under 21 and 11 percent of drivers ages 21–24 were
in serious accidents. By contrast, only 3 percent
of licensed drivers 65 and older were involved in
serious accidents. These gures clearly show that the
greater experience and developed habits of caution
possessed by drivers in the 65-and-older group make
them far safer behind the wheel than the younger
drivers are.
Which of the following is an assumption on which the
argument depends?
(A) Drivers 65 and older do not, on average, drive
very many fewer miles per year than drivers 24
and younger.
(B) Drivers 65 and older do not constitute a
signi cantly larger percentage of licensed drivers
in Wareland than drivers ages 18–24 do.
(C) Drivers 65 and older are less likely than are
drivers 24 and younger to drive during weather
conditions that greatly increase the risk of
accidents.
(D) The difference between the accident rate of
drivers under 21 and of those ages 21–24 is
attributable to the greater driving experience of
those in the older group.
(E) There is no age bracket for which the accident
rate is lower than it is for licensed drivers 65 and
older.
636. In the past the country of Malvernia has relied heavily
on imported oil. Malvernia recently implemented a
program to convert heating systems from oil to natural
gas. Malvernia currently produces more natural gas
each year than it uses, and oil production in Malvernian
oil elds is increasing at a steady pace. If these trends
in fuel production and usage continue, therefore,
Malvernian reliance on foreign sources for fuel is likely
to decline soon.
Which of the following would it be most useful to
establish in evaluating the argument?
(A) When, if ever, will production of oil in Malvernia
outstrip production of natural gas?
(B) Is Malvernia among the countries that rely most
on imported oil?
(C) What proportion of Malvernia’s total energy
needs is met by hydroelectric, solar, and nuclear
power?
(D) Is the amount of oil used each year in
Malvernia for generating electricity and fuel for
transportation increasing?
(E) Have any existing oil‐burning heating systems
in Malvernia already been converted to natural‐
gas‐burning heating systems?
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637. Exposure to certain chemicals commonly used in
elementary schools as cleaners or pesticides causes
allergic reactions in some children. Elementary
school nurses in Renston report that the proportion
of schoolchildren sent to them for treatment of
allergic reactions to those chemicals has increased
signi cantly over the past ten years. Therefore, either
Renston’s schoolchildren have been exposed to greater
quantities of the chemicals, or they are more sensitive
to them than schoolchildren were ten years ago.
Which of the following is an assumption on which the
argument depends?
(A) The number of school nurses employed by
Renston’s elementary schools has not decreased
over the past ten years.
(B) Children who are allergic to the chemicals are no
more likely than other children to have allergies
to other substances.
(C) Children who have allergic reactions to the
chemicals are not more likely to be sent to a
school nurse now than they were ten years ago.
(D) The chemicals are not commonly used as
cleaners or pesticides in houses and apartment
buildings in Renston.
(E) Children attending elementary school do not
make up a larger proportion of Renston’s
population now than they did ten years ago.
638. Normally, the pineal gland governs a person’s
sleep-wake cycle by secreting melatonin in response to
the daily cycle of light and darkness as detected by the
eye. Nonetheless, many people who are totally blind due
to lesions in the visual cortex of the brain easily maintain
a 24‐hour sleep‐wake cycle. So the neural pathway by
which the pineal gland receives information from the eye
probably does not pass through the visual cortex.
For purposes of evaluating the argument it would be
most useful to establish which of the following?
(A) Whether melatonin supplements help people who
have dif culty maintaining a 24‐hour sleep cycle
to establish such a pattern
(B) Whether the melatonin levels of most totally
blind people who successfully maintain a 24‐hour
sleep‐wake cycle change in response to changes
in exposure to light and darkness
(C) Whether melatonin is the only substance
secreted by the pineal gland
(D) Whether most people who do not have a 24‐hour
sleep‐wake cycle nevertheless have a cycle of
consistent duration
(E) Whether there are any people with normal vision
whose melatonin levels respond abnormally to
periods of light and darkness
639. In countries where automobile insurance includes
compensation for whiplash injuries sustained in
automobile accidents, reports of having suffered
such injuries are twice as frequent as they are
in countries where whiplash is not covered.
Presently, no objective test for whiplash exists, so it is
true that spurious reports of whiplash injuries cannot
be readily identi ed. Nevertheless, these facts do not
warrant the conclusion drawn by some commentators
that in the countries with the higher rates of reported
whiplash injuries, half of the reported cases are
spurious. Clearly, in countries where automobile
insurance does not include compensation for
whiplash, people often have little incentive to
report whiplash injuries that they actually have
suffered.
In the argument given, the two boldfaced portions play
which of the following roles?
(A) The rst is a claim that the argument disputes;
the second is a conclusion that has been based
on that claim.
(B) The rst is a claim that has been used to support
a conclusion that the argument accepts; the
second is that conclusion.
(C) The rst is evidence that has been used to
support a conclusion for which the argument
provides further evidence; the second is the
main conclusion of the argument.
(D) The rst is a nding whose implications are at
issue in the argument; the second is a claim
presented in order to argue against deriving
certain implications from that nding.
(E) The rst is a nding whose accuracy is evaluated
in the argument; the second is evidence
presented to establish that the nding is accurate.
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640. Last year Comfort Airlines had twice as many
delayed ights as the year before, but the number of
complaints from passengers about delayed ights went
up three times. It is unlikely that this disproportionate
increase in complaints was rooted in an increase in
overall dissatisfaction with the service Comfort Airlines
provides, since the airline made a special effort to
improve other aspects of its service last year.
Which of the following, if true, most helps to explain
the disproportionate increase in customer complaints?
(A) Comfort Airlines had more ights last year than
the year before.
(B) Last year a single period of unusually bad
weather caused a large number of ights to be
delayed.
(C) Some of the improvements that Comfort Airlines
made in its service were required by new
government regulations.
(D) The average length of a ight delay was greater
last year than it was the year before.
(E) The average number of passengers per ight
was no higher last year than the year before.
641. Last year a global disturbance of weather patterns
disrupted harvests in many of the world’s important
agricultural areas. Worldwide production of soybeans,
an important source of protein for people and livestock
alike, was not adversely affected, however. Indeed, last
year’s soybean crop was actually slightly larger than
average. Nevertheless, the weather phenomenon is
probably responsible for a recent increase in the world
price of soybeans.
Which of the following, if true, provides the strongest
justi cation for the attribution of the increase in
soybean prices to the weather phenomenon?
(A) Last year’s harvest of anchovies, which provide
an important protein source for livestock,
was disrupted by the effects of the weather
phenomenon.
(B) Most countries that produce soybeans for export
had above‐average harvests of a number of food
crops other than soybeans last year.
(C) The world price of soybeans also rose
several years ago, immediately after an
earlier occurrence of a similar global weather
disturbance.
(D) Heavy rains attributable to the weather
phenomenon improved grazing pastures last
year, allowing farmers in many parts of the world
to reduce their dependence on supplemental
feed.
(E) Prior to last year, soybean prices had been
falling for several years.
642. Most of the year, the hermit thrush, a North American
songbird, eats a diet consisting mainly of insects, but
in autumn, as the thrushes migrate to their Central and
South American wintering grounds, they feed almost
exclusively on wild berries. Wild berries, however, are
not as rich in calories as insects, yet thrushes need to
consume plenty of calories in order to complete their
migration. One possible explanation is that berries
contain other nutrients that thrushes need for migration
and that insects lack.
Which of the following, if true, most seriously calls into
question the explanation given for the thrush’s diet
during migration?
(A) Hermit thrushes, if undernourished, are unable
to complete their autumn migration before the
onset of winter.
(B) Insect species contain certain nutrients that are
not found in wild berries.
(C) For songbirds, catching insects requires the
expenditure of signi cantly more calories than
eating wild berries does.
(D) Along the hermit thrushes’ migration routes,
insects are abundant throughout the migration
season.
(E) There are some species of wild berries that
hermit thrushes generally do not eat, even
though these berry species are exceptionally
rich in calories.
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643. The kinds of hand and wrist injuries that result from
extended use of a computer while maintaining an
incorrect posture are common among schoolchildren
in Harnville. Computers are important to the school
curriculum there, so instead of reducing the amount
their students use computers, teachers plan to bring
about a sharp reduction in the number of these
injuries by carefully monitoring their
students’ posture when using computers in the
classroom.
Which of the following would it be most useful to know
in order to assess the likelihood that the teachers’ plan
will be successful?
(A) Whether extended use of a computer while
maintaining incorrect posture can cause injuries
other than hand and wrist injuries
(B) Whether hand and wrist injuries not caused
by computer use are common among
schoolchildren in Harnville
(C) What proportion of schoolchildren in Harnville
with hand and wrist injuries use computers
extensively outside the classroom
(D) Whether changes in the curriculum could reduce
the schools’ dependence on computers
(E) What proportion of schoolchildren in Harnville
already use correct posture while using a
computer
644. A certain cultivated herb is one of a group of
closely related plants that thrive in soil with high
concentrations of metals that are toxic to most other
plants. Agronomists studying the growth of this herb
have discovered that it produces large amounts of
histidine, an amino acid that, in test‐tube solutions,
renders these metals chemically inert. Hence, the
herb’s high histidine production must be the key
feature that allows it to grow in metal‐rich soils.
In evaluating the argument, it would be most important
to determine which of the following?
(A) Whether the herb can thrive in soil that does
not have high concentrations of the toxic
metals
(B) Whether others of the closely related group
of plants also produce histidine in large
quantities
(C) Whether the herb’s high level of histidine
production is associated with an unusually low
level of production of some other amino acid
(D) Whether growing the herb in soil with high
concentrations of the metals will, over time,
reduce their concentrations in the soil
(E) Whether the concentration of histidine in the
growing herb declines as the plant approaches
maturity
645. Many people suffer an allergic reaction to certain
sul tes, including those that are commonly added
to wine as preservatives. However, since there are
several winemakers who add sul tes to none of
the wines they produce, people who would like to
drink wine but are allergic to sul tes can drink wines
produced by these winemakers without risking an
allergic reaction to sul tes.
Which of the following is an assumption on which the
argument depends?
(A) These winemakers have been able to duplicate
the preservative effect produced by adding
sul tes by means that do not involve adding any
potentially allergenic substances to their wine.
(B) Not all forms of sul te are equally likely to
produce the allergic reaction.
(C) Wine is the only beverage to which sul tes are
commonly added.
(D) Apart from sul tes, there are no substances
commonly present in wine that give rise to an
allergic reaction.
(E) Sul tes are not naturally present in the wines
produced by these winemakers in amounts
large enough to produce an allergic reaction in
someone who drinks these wines.
646. A new law gives ownership of patents—documents
providing exclusive right to make and sell an
invention—to universities, not the government, when
those patents result from government‐sponsored
university research. Administrators at Logos University
plan to sell any patents they acquire to corporations
in order to fund programs to improve undergraduate
teaching.
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Which of the following, if true, would cast the most
doubt on the viability of the college administrators’
plan described above?
(A) Profit‐making corporations interested in
developing products based on patents held by
universities are likely to try to serve as exclusive
sponsors of ongoing university research
projects.
(B) Corporate sponsors of research in university
facilities are entitled to tax credits under new
federal tax‐code guidelines.
(C) Research scientists at Logos University have few
or no teaching responsibilities and participate
little if at all in the undergraduate programs in
their field.
(D) Government‐sponsored research conducted at
Logos University for the most part duplicates
research already completed by several
profitmaking corporations.
(E) Logos University is unlikely to attract corporate
sponsorship of its scientific research.
647. Since it has become known that several of a bank’s
top executives have been buying shares in their
own bank, the bank’s depositors, who had been
worried by rumors that the bank faced impending
nancial collapse, have been greatly relieved. They
reason that, since top executives evidently have faith
in the bank’s nancial soundness, those worrisome
rumors must be false. Such reasoning might well
be overoptimistic, however, since corporate
executives have been known to buy shares in
their own company in a calculated attempt to
dispel negative rumors about the company’s
health.
In the argument given, the two boldfaced portions play
which of the following roles?
(A) The rst describes evidence that has been taken
as supporting a conclusion; the second gives a
reason for questioning that support.
(B) The rst describes evidence that has been taken
as supporting a conclusion; the second states a
contrary conclusion that is the main conclusion
of the argument.
(C) The rst provides evidence in support of the
main conclusion of the argument; the second
states that conclusion.
(D) The rst describes the circumstance that the
argument as a whole seeks to explain; the
second gives the explanation that the argument
seeks to establish.
(E) The rst describes the circumstance that
the argument as a whole seeks to explain;
the second provides evidence in support of
the explanation that the argument seeks to
establish.
648. Between 1980 and 2000 the sea otter population
of the Aleutian Islands declined precipitously. There
were no signs of disease or malnutrition, so there
was probably an increase in the number of otters
being eaten by predators. Orcas will eat otters when
seals, their normal prey, are unavailable, and the
Aleutian Islands seal population declined dramatically
in the 1980s. Therefore, orcas were most likely the
immediate cause of the otter population decline.
Which of the following, if true, most strengthens the
argument?
(A) The population of sea urchins, the main food of
sea otters, has increased since the sea otter
population declined.
(B) Seals do not eat sea otters, nor do they
compete with sea otters for food.
(C) Most of the surviving sea otters live in a bay that
is inaccessible to orcas.
(D) The population of orcas in the Aleutian Islands
has declined since the 1980s.
(E) An increase in commercial shing near the
Aleutian Islands in the 1980s caused a slight
decline in the population of the sh that seals
use for food.
8.4 Critical Reasoning Practice Questions
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649. Studies in restaurants show that the tips left by
customers who pay their bill in cash tend to be larger
when the bill is presented on a tray that bears a
credit-card logo. Consumer psychologists hypothesize
that simply seeing a credit‐card logo makes many
credit-card holders willing to spend more because it
reminds them that their spending power exceeds the
cash they have immediately available.
Which of the following, if true, most strongly supports
the psychologists’ interpretation of the studies?
(A) The effect noted in the studies is not limited to
patrons who have credit cards.
(B) Patrons who are under nancial pressure from
their credit‐card obligations tend to tip less when
presented with a restaurant bill on a tray with a
credit‐card logo than when the tray has no logo.
(C) In virtually all of the cases in the studies, the
patrons who paid bills in cash did not possess
credit cards.
(D) In general, restaurant patrons who pay their bills
in cash leave larger tips than do those who pay
by credit card.
(E) The percentage of restaurant bills paid with a
given brand of credit card increases when that
credit card’s logo is displayed on the tray with
which the bill is presented.
650. In an experiment, each volunteer was allowed to
choose between an easy task and a hard task and was
told that another volunteer would do the other task.
Each volunteer could also choose to have a computer
assign the two tasks randomly. Most volunteers chose
the easy task for themselves and under questioning
later said they had acted fairly. But when the scenario
was described to another group of volunteers, almost
all said choosing the easy task would be unfair. This
shows that most people apply weaker moral standards
to themselves than to others.
Which of the following is an assumption required by
this argument?
(A) At least some volunteers who said they had
acted fairly in choosing the easy task would have
said that it was unfair for someone else to do so.
(B) The most moral choice for the volunteers would
have been to have the computer assign the two
tasks randomly.
(C) There were at least some volunteers who were
assigned to do the hard task and felt that the
assignment was unfair.
(D) On average, the volunteers to whom the scenario
was described were more accurate in their moral
judgments than the other volunteers were.
(E) At least some volunteers given the choice
between assigning the tasks themselves and
having the computer assign them felt that they
had made the only fair choice available to them.
651. Country X’s recent stock-trading scandal should not
diminish investors’ con dence in the country’s stock
market. For one thing, the discovery of the scandal
con rms that Country X has a strong regulatory
system, as the following considerations show. In any
stock market, some fraudulent activity is inevitable.
If a stock market is well regulated, any signi cant
stock-trading fraud in it will very likely be discovered.
This deters potential perpetrators and facilitates
improvement in regulatory processes.
In the argument, the portion in boldface plays which of
the following roles?
(A) It is the argument’s only conclusion.
(B) It is a conclusion for which the argument
provides support and which itself is used to
support the argument’s main conclusion.
(C) It is the argument’s main conclusion and is
supported by another explicitly stated conclusion
for which further support is provided.
(D) It is an assumption for which no explicit
support is provided and is used to support the
argument’s only conclusion.
(E) It is a compound statement containing both the
argument’s main conclusion and an assumption
used to support that conclusion.
652. Delta Products Inc. has recently switched at least
partly from older technologies using fossil fuels
to new technologies powered by electricity. The
question has been raised whether it can be concluded
that for a given level of output Delta’s operation
now causes less fossil fuel to be consumed than
it did formerly. The answer, clearly, is yes, since the
amount of fossil fuel used to generate the electricity
needed to power the new technologies is less than
the amount needed to power the older technologies,
provided level of output is held constant.
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541
In the argument given, the two boldfaced portions play
which of the following roles?
(A) The rst identi es the content of the conclusion
of the argument; the second provides support
for that conclusion.
(B) The rst provides support for the conclusion of
the argument; the second identi es the content
of that conclusion.
(C) The rst states the conclusion of the argument;
the second calls that conclusion into question.
(D) The rst provides support for the conclusion of
the argument; the second calls that conclusion
into question.
(E) Each provides support for the conclusion of the
argument.
653. Theater Critic: The play La Finestrina, now at Central
Theater, was written in Italy in the eighteenth century.
The director claims that this production is as similar
to the original production as is possible in a modern
theater. Although the actor who plays Harlequin the
clown gives a performance very reminiscent of the
twentieth‐century American comedian Groucho Marx,
Marx’s comic style was very much within the comic
acting tradition that had begun in sixteenth‐century Italy.
The considerations given best serve as part of an
argument that
(A) modern audiences would nd it hard to tolerate
certain characteristics of a historically accurate
performance of an eighteenth‐century play
(B) Groucho Marx once performed the part of the
character Harlequin in La Finestrina
(C) in the United States the training of actors in the
twentieth century is based on principles that do
not differ radically from those that underlay the
training of actors in eighteenth‐century Italy
(D) the performance of the actor who plays
Harlequin in La Finestrina does not serve as
evidence against the director’s claim
(E) the director of La Finestrina must have advised the
actor who plays Harlequin to model his performance
on comic performances of Groucho Marx
654. Although the discount stores in Goreville’s central
shopping district are expected to close within ve
years as a result of competition from a SpendLess
discount department store that just opened, those
locations will not stay vacant for long. In the ve
years since the opening of Colson’s, a nondiscount
department store, a new store has opened at the
location of every store in the shopping district that
closed because it could not compete with Colson’s.
Which of the following, if true, most seriously weakens
the argument?
(A) Many customers of Colson’s are expected to
do less shopping there than they did before the
SpendLess store opened.
(B) Increasingly, the stores that have opened in the
central shopping district since Colson’s opened
have been discount stores.
(C) At present, the central shopping district has as
many stores operating in it as it ever had.
(D) Over the course of the next ve years, it is
expected that Goreville’s population will grow at a
faster rate than it has for the past several decades.
(E) Many stores in the central shopping district sell
types of merchandise that are not available at
either SpendLess or Colson’s.
655. Last year all refuse collected by Shelbyville city services
was incinerated. This incineration generated a large
quantity of residual ash. In order to reduce the amount of
residual ash Shelbyville generates this year to half of last
year’s total, the city has revamped its collection program.
This year city services will separate for recycling enough
refuse to reduce the number of truckloads of refuse to be
incinerated to half of last year’s number.
Which of the following is required for the revamped
collection program to achieve its aim?
(A) This year, no materials that city services could
separate for recycling will be incinerated.
(B) Separating recyclable materials from materials to
be incinerated will cost Shelbyville less than half
what it cost last year to dispose of the residual ash.
(C) Refuse collected by city services will contain
a larger proportion of recyclable materials this
year than it did last year.
(D) The refuse incinerated this year will generate no
more residual ash per truckload incinerated than
did the refuse incinerated last year.
(E) The total quantity of refuse collected by
Shelbyville city services this year will be no
greater than that collected last year.
8.4 Critical Reasoning Practice Questions
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656. Veterinarians generally derive some of their income
from selling several manufacturers’ lines of pet-care
products. Knowing that pet owners rarely throw
away mail from their pet’s veterinarian unread, one
manufacturer of pet-care products offered free
promotional materials on its products to veterinarians
for mailing to their clients. Very few veterinarians
accepted the offer, however, even though the
manufacturer’s products are of high quality.
Which of the following, if true, most helps to explain
the veterinarians’ reaction to the manufacturer’s
promotional scheme?
(A) Most of the veterinarians to whom the free
promotional materials were offered were already
selling the manufacturer’s pet-care products to
their clients.
(B) The special promotional materials were
intended as a supplement to the manufacturer’s
usual promotional activities rather than as a
replacement for them.
(C) The manufacturer’s products, unlike most
equally good competing products sold by
veterinarians, are also available in pet stores and
in supermarkets.
(D) Many pet owners have begun demanding quality
in products they buy for their pets that is as high
as that in products they buy for themselves.
(E) Veterinarians sometimes recommend that pet
owners use products formulated for people when
no suitable product specially formulated for
animals is available.
657. The average hourly wage of television assemblers in
Vernland has long been signi cantly lower than that in
neighboring Borodia. Since Borodia dropped all tariffs
on Vernlandian televisions three years ago, the number
of televisions sold annually in Borodia has not changed.
However, recent statistics show a drop in the number
of television assemblers in Borodia. Therefore, updated
trade statistics will probably indicate that the number
of televisions Borodia imports annually from Vernland
has increased.
Which of the following is an assumption on which the
argument depends?
(A) The number of television assemblers in Vernland
has increased by at least as much as the number
of television assemblers in Borodia has decreased.
(B) Televisions assembled in Vernland have
features that televisions assembled in
Borodia do not have.
(C) The average number of hours it takes a
Borodian television assembler to assemble a
television has not decreased signi cantly during
the past three years.
(D) The number of televisions assembled annually in
Vernland has increased signi cantly during the
past three years.
(E) The difference between the hourly wage of
television assemblers in Vernland and the hourly
wage of television assemblers in Borodia is likely
to decrease in the next few years.
658. Guidebook writer: I have visited hotels throughout the
country and have noticed that in those built before
1930 the quality of the original carpentry work is
generally superior to that in hotels built afterward.
Clearly carpenters working on hotels before 1930
typically worked with more skill, care, and effort
than carpenters who have worked on hotels built
subsequently.
Which of the following, if true, most seriously weakens
the guidebook writer’s argument?
(A) The quality of original carpentry in hotels is
generally far superior to the quality of original
carpentry in other structures, such as houses
and stores.
(B) Hotels built since 1930 can generally
accommodate more guests than those built
before 1930.
(C) The materials available to carpenters working
before 1930 were not signi cantly different in
quality from the materials available to carpenters
working after 1930.
(D) The better the quality of original carpentry in a
building, the less likely that building is to fall into
disuse and be demolished.
(E) The average length of apprenticeship for
carpenters has declined signi cantly since
1930.
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543
659. Scientists typically do their most creative work
before the age of forty. It is commonly thought
that this happens because aging by itself brings
about a loss of creative capacity. However, studies
show that of scientists who produce highly
creative work beyond the age of forty, a
disproportionately large number entered their
eld at an older age than is usual . Since by the
age of forty the large majority of scientists have
been working in their eld for at least fteen years,
the studies’ nding strongly suggests that the real
reason why scientists over forty rarely produce
highly creative work is not that they have aged but
rather that scientists over forty have generally
spent too long in their eld .
In the argument given, the two portions in boldface
play which of the following roles?
(A) The rst is a claim, the accuracy of which
is at issue in the argument; the second is a
conclusion drawn on the basis of that claim.
(B) The rst is an objection that has been raised
against a position defended in the argument; the
second is that position.
(C) The rst is evidence that has been used to
support an explanation that the argument
challenges; the second is that explanation.
(D) The rst is evidence that has been used to
support an explanation that the argument
challenges; the second is a competing
explanation that the argument favors.
(E) The rst provides evidence to support an
explanation that the argument favors; the second
is that explanation.
660. NorthAir charges low fares for its economy-class
seats, but it provides very cramped seating and few
amenities. Market research shows that economy
passengers would willingly pay more for wider seating
and better service, and additional revenue provided
by these higher ticket prices would more than cover
the additional cost of providing these amenities. Even
though NorthAir is searching for ways to improve
its pro tability, it has decided not to make these
improvements.
Which of the following, if true, would most help to
explain NorthAir’s decision in light of its objectives?
(A) None of NorthAir’s competitors offers
signi cantly better seating and service to
economy-class passengers than NorthAir
does.
(B) On many of the routes that NorthAir ies, it is the
only airline to offer direct ights.
(C) A few of NorthAir’s economy-class passengers
are satis ed with the service they receive, given
the low price they pay.
(D) Very few people avoid ying on NorthAir because
of the cramped seating and poor service offered
in economy class.
(E) The number of people who would be willing
to pay the high fares NorthAir charges for its
business-class seats would decrease if its
economy-class seating were more acceptable.
661. Which of the following most logically completes the
argument given?
Asthma, a chronic breathing disorder, is signi cantly
more common today among adult competitive
swimmers than it is among competitive athletes who
specialize in other sports. Although chlorine is now
known to be a lung irritant and swimming pool water
is generally chlorinated, it would be rash to assume
that frequent exposure to chlorine is the explanation of
the high incidence of asthma among these swimmers,
since __________.
(A) young people who have asthma are no more
likely to become competitive athletes than are
young people who do not have asthma
(B) competitive athletes who specialize in sports
other than swimming are rarely exposed to
chlorine
(C) competitive athletes as a group have a
signi cantly lower incidence of asthma than do
people who do not participate in competitive
athletics
(D) until a few years ago, physicians routinely
recommended competitive swimming to children
with asthma, in the belief that this form of
exercise could alleviate asthma symptoms
(E) many people have asthma without knowing
they have it and thus are not diagnosed with
the condition until they begin engaging in very
strenuous activities, such as competitive athletics
8.4 Critical Reasoning Practice Questions
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662. In the country of Marut, the Foreign Trade Agency’s
records were reviewed in 1994 in light of information
then newly available about neighboring Goro. The
review revealed that in every year since 1963, the
agency’s projection of what Goro’s gross national
product (GNP) would be ve years later was a serious
underestimate. The review also revealed that in every
year since 1963, the agency estimated Goro’s GNP
for the previous year—a Goro state secret—very
accurately.
Of the following claims, which is most strongly
supported by the statements given?
(A) Goro’s GNP uctuated greatly between 1963 and
1994.
(B) Prior to 1995, Goro had not released data
intended to mislead the agency in making its ve‐
year projections.
(C) The amount by which the agency underestimated
the GNP it projected for Goro tended to increase
over time.
(D) Even before the new information came to light,
the agency had reason to think that at least
some of the ve‐year projections it had made
were inaccurate.
(E) The agency’s ve‐year projections of Goro’s GNP
had no impact on economic planning in Marut.
663. Vargonia has just introduced a legal requirement that
student‐teacher ratios in government‐funded schools
not exceed a certain limit. All Vargonian children are
entitled to education, free of charge, in these schools.
When a recession occurs and average incomes fall,
the number of children enrolled in government‐funded
schools tends to increase. Therefore, though most
employment opportunities contract in economic
recessions, getting a teaching job in Vargonia’s
government‐funded schools will not be made more
dif cult by a recession.
Which of the following would be most important to
determine in order to evaluate the argument?
(A) Whether in Vargonia there are any schools not
funded by the government that offer children an
education free of charge
(B) Whether the number of quali ed applicants
for teaching positions in government‐funded
schools increases signi cantly during economic
recessions
(C) What the current student‐teacher ratio in
Vargonia’s government‐funded schools is
(D) What proportion of Vargonia’s workers currently
hold jobs as teachers in government‐funded
schools
(E) Whether in the past a number of government-
funded schools in Vargonia have had student-
teacher ratios well in excess of the new limit
664. In Colorado subalpine meadows, nonnative dandelions
co‐occur with a native ower, the larkspur. Bumblebees
visit both species, creating the potential for
interactions between the two species with respect to
pollination. In a recent study, researchers selected
16 plots containing both species; all dandelions were
removed from eight plots; the remaining eight control
plots were left undisturbed. The control plots yielded
signi cantly more larkspur seeds than the dandelion‐
free plots, leading the researchers to conclude that
the presence of dandelions facilitates pollination
(and hence seed production) in the native species by
attracting more pollinators to the mixed plots.
Which of the following, if true, most seriously
undermines the researchers’ reasoning?
(A) Bumblebees preferentially visit dandelions over
larkspurs in mixed plots.
(B) In mixed plots, pollinators can transfer pollen
from one species to another to augment seed
production.
(C) If left unchecked, nonnative species like
dandelions quickly crowd out native species.
(D) Seed germination is a more reliable measure of
a species’ tness than seed production.
(E) Soil disturbances can result in fewer blooms, and
hence lower seed production.
665. An experiment was done in which human subjects
recognize a pattern within a matrix of abstract designs
and then select another design that completes that
pattern. The results of the experiment were surprising.
The lowest expenditure of energy in neurons in the
brain was found in those subjects who performed most
successfully in the experiments.
Which of the following hypotheses best accounts for
the findings of the experiment?
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3.2 Diagnostic Test Verbal Questions
545
(A) The neurons of the brain react less when a
subject is trying to recognize patterns than when
the subject is doing other kinds of reasoning.
(B) Those who performed best in the experiment
experienced more satisfaction when working with
abstract patterns than did those who performed
less well.
(C) People who are better at abstract pattern
recognition have more energy‐efficient neural
connections.
(D) The energy expenditure of the subjects’ brains
increases when a design that completes the
initially recognized pattern is determined.
(E) The task of completing a given design is more
capably performed by athletes, whose energy
expenditure is lower when they are at rest.
666. With seventeen casinos, Moneyland operates the
most casinos in a certain state. Although intent on
expanding, it was outmaneuvered by Apex Casinos
in negotiations to acquire the Eldorado chain. To
complete its acquisition of Eldorado, Apex must sell
ve casinos to comply with a state law forbidding any
owner to operate more than one casino per county.
Since Apex will still be left operating twenty casinos
in the state, it will then have the most casinos in the
state.
Which of the following, if true, most seriously
undermines the prediction?
(A) Apex, Eldorado, and Moneyland are the only
organizations licensed to operate casinos in the
state.
(B) The majority of Eldorado’s casinos in the state
will need extensive renovations if they are to
continue to operate pro tably.
(C) Some of the state’s counties do not permit
casinos.
(D) Moneyland already operates casinos in the
majority of the state’s counties.
(E) Apex will use funds it obtains from the sale of
the ve casinos to help fund its acquisition of the
Eldorado chain.
667. It is widely assumed that people need to engage
in intellectual activities such as solving crossword
puzzles or mathematics problems in order to maintain
mental sharpness as they age. In fact, however,
simply talking to other people—that is, participating
in social interaction, which engages many mental and
perceptual skills—suf ces. Evidence to this effect
comes from a study showing that the more social
contact people report, the better their mental skills.
Which of the following, if true, most seriously weakens
the force of the evidence cited?
(A) As people grow older, they are often advised
to keep exercising their physical and mental
capacities in order to maintain or improve them.
(B) Many medical conditions and treatments that
adversely affect a person’s mental sharpness
also tend to increase that person’s social
isolation.
(C) Many people are pro cient both in social
interactions and in solving mathematical
problems.
(D) The study did not itself collect data but analyzed
data bearing on the issue from prior studies.
(E) The tasks evaluating mental sharpness for which
data were compiled by the study were more akin
to mathematics problems than to conversation.
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GMAT® Offi cial Guide 2018
544. E
545. C
546. E
547. A
548. A
549. B
550. E
551. E
552. C
553. E
554. A
555. A
556. D
557. B
558. C
559. A
560. C
561. B
562. D
563. D
564. C
565. E
566. E
567. E
568. B
569. A
570. E
571. B
572. E
573. D
574. D
575. E
576. C
577. E
578. D
579. E
580. A
581. A
582. C
583. D
584. E
585. C
586. D
587. C
588. D
589. C
590. E
591. C
592. D
593. A
594. A
595. D
596. C
597. E
598. C
599. C
600. A
601. E
602. D
603. A
604. D
605. A
606. E
607. C
608. A
609. C
610. E
611. A
612. D
613. D
614. C
615. D
616. E
617. D
618. D
619. A
620. A
621. D
622. A
623. E
624. E
625. A
626. D
627. E
628. E
629. E
630. B
631. E
632. D
633. D
634. B
635. A
636. D
637. C
638. B
639. D
640. D
641. A
642. C
643. C
644. B
645. E
646. D
647. A
648. C
649. B
650. A
651. B
652. B
653. D
654. B
655. D
656. C
657. C
658. D
659. E
660. E
661. D
662. D
663. B
664. E
665. C
666. A
667. B
8.5 Answer Key
547
8.6 Critical Reasoning Answer Explanations
544. Neuroscientist: Memory evolved to help animals react appropriately to situations they encounter by drawing on the past
experience of similar situations. But this does not require that animals perfectly recall every detail of all their experiences.
Instead, to function well, memory should generalize from past experiences that are similar to the current one.
The neuroscientist’s statements, if true, most strongly support which of the following conclusions?
(A) At least some animals perfectly recall every detail of at least some past experiences.
(B) Perfectly recalling every detail of all their past experiences could help at least some animals react more appropriately
than they otherwise would to new situations they encounter.
(C) Generalizing from past experiences requires clear memories of most if not all the details of those experiences.
(D) Recalling every detail of all past experiences would be incompatible with any ability to generalize from those
experiences.
(E) Animals can often react more appropriately than they otherwise would to situations they encounter if they draw on
generalizations from past experiences of similar situations.
Argument Construction
Situation A neuroscientist claims that memory evolved to help animals learn how to react appropriately by
generalizing from past experiences but that this does not require animals to remember all details of
those experiences.
Reasoning What conclusion would the neuroscientist’s theory about memory most strongly support? e
neuroscientist asserts that the evolutionary function of memory is to help animals learn to react
appropriately by drawing on generalizations from similar experiences they have had. If memory is
to serve this function, drawing on generalizations must actually help animals learn to react more
appropriately than they otherwise would, even when they do not remember all the details of past
experiences.
A Even if no animal ever recalls all the details of any past experience, animals could still learn through
generalizations, as the neuroscientist claims.
B is statement could be false even if all of what the neuroscientist says is true. Even if it were never
helpful
for any animal to recall every detail of all its past experiences, animals could still bene t by learning
through generalizations.
C Generalizations from experiences might be made while the experiences are occurring, so that only the
generalizations and not the details need to be remembered.
D e neuroscientist only claims that remembering perfect details is not required for memory to serve its
function, not that such perfect recall is incompatible with memory serving its function.
E Correct. If the evolutionary function of memory is to help animals react more appropriately by drawing
on generalizations from past experiences, it follows that animal memories can often successfully serve this
function in this manner.
e correct answer is E.
8.6 Answer Explanations
The following discussion is intended to familiarize you with the most efficient and effective approaches
to critical reasoning questions. The particular questions in this chapter are generally representative of
the kinds of critical reasoning questions you will encounter on the GMAT exam. Remember that it is the
problem solving strategy that is important, not the specific details of a particular question.
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545. Astronomer: Most stars are born in groups of thousands, each star in a group forming from the same parent cloud of gas.
Each cloud has a unique, homogeneous chemical composition. Therefore, whenever two stars have the same chemical
composition as each other, they must have originated from the same cloud of gas.
Which of the following, if true, would most strengthen the astronomer’s argument?
(A) In some groups of stars, not every star originated from the same parent cloud of gas.
(B) Clouds of gas of similar or identical chemical composition may be remote from each other.
(C) Whenever a star forms, it inherits the chemical composition of its parent cloud of gas.
(D) Many stars in vastly different parts of the universe are quite similar in their chemical compositions.
(E) Astronomers can at least sometimes precisely determine whether a star has the same chemical composition as its
parent cloud of gas.
Argument Evaluation
Situation Most stars are born in groups, any one of which forms from a parent gas cloud with a unique,
homogenous chemical composition.
Reasoning What would be additional evidence that any two stars with the same chemical composition
originated from the same gas cloud? e implicit reasoning is that since the chemical composition
of each gas cloud is unique and homogenous, any two stars that formed from gas with the same
chemical composition must have originated from the same cloud. e astronomer then infers that
if two stars have the same composition now,they must have originated from the same cloud. is
inference requires the assumption that the composition each star has now depends only on the
composition of the cloud in which it originated. Any evidence that supports this assumption will
strengthen the argument.
A Whether or not stars born in di erent clouds of gas are ever in the same “group” is not clearly relevant to
whether or not they ever have the same chemical composition.
B How remote clouds of similar compositions are from each other is not clearly relevant to whether
stars that have the same chemical composition may have formed from di erent clouds of gas. Also, the
suggestion that di erent gas clouds may have identical compositions con icts with the astronomer’s
premise that the composition of each cloud from which stars form is unique.
C Correct. If each star’s composition is identical to that of its parent cloud, and each cloud’s composition is
unique, then any two stars identical in composition must have formed from the same parent cloud.
D If anything, this would suggest that stars with the same composition might have formed from di erent
clouds, so it would weaken rather than strengthen the argument.
E If astronomers could do this, they might be able to obtain additional evidence for or against the position
taken in the argument, but this, in itself, provides no reason to suppose that the evidence would support,
rather than weaken, that position. ey might nd that the stars’ compositions do not precisely correlate
with the compositions of the stars’ parent gas clouds.
e correct answer is C.
549
8.6 Critical Reasoning Answer Explanations
546. With employer-paid training, workers have the potential to become more productive not only in their present employment but
also in any number of jobs with different employers. To increase the productivity of their workforce, many rms are planning to
maintain or even increase their investments in worker training. But some training experts object that if a trained worker is hired
away by another rm, the employer that paid for the training has merely subsidized a competitor. They note that such hiring
has been on the rise in recent years.
Which of the following would, if true, contribute most to defeating the training experts’ objection to the rms’ strategy?
(A) Firms that promise opportunities for advancement to their employees get, on average, somewhat larger numbers of
job applications from untrained workers than do rms that make no such promise.
(B) In many industries, employees that take continuing-education courses are more competitive in the job market.
(C) More and more educational and training institutions are offering reduced tuition fees to rms that subsidize worker
training.
(D) Research shows that workers whose training is wholly or partially subsidized by their employer tend to get at least as
much training as do workers who pay for all their own training.
(E) For most rms that invest in training their employees, the value added by that investment in employees who stay
exceeds the value lost through other employees’ leaving to work for other companies.
Evaluation of a Plan
Situation Many rms pay to train their workers in order to increase their workforces’ productivity. But in
recent years rms have been increasingly hiring away from each other workers who have had such
training.
Reasoning What would most help address the concern that rms that pay to train workers are thereby subsidizing
competitors that hire away those workers? In order for the employer-paid training to be worthwhile
for a given rm despite the risk of subsidizing competitors that may hire away the trained workers,
that rm has to gain more bene ts from the training than it loses by subsidizing such competitors.
Any evidence that this is true for most rms would help to address the experts’ concern.
A A typical rm does not necessarily want larger numbers of applications from unquali ed workers. And if
hired, those workers can still be hired away by competitors after the rm has paid to train them, just as the
experts warned.
B is suggests that in many industries, companies, rather than investing in employee training, prefer to
hire employees who already have speci cally relevant training (perhaps funded by other companies). If
anything, this slightly supports, rather than defeats, the training experts’ view. No rm has an interest in
making its own employees more competitive in the job market unless the rm is likely to bene t from
their being so.
C Even rms that pay reduced tuition fees for worker training may lose the money they pay for those fees
and e ectively subsidize competitors that hire the trained employees away. So this does not defeat the
training experts’ objection.
D e more highly trained workers—regardless of whether their training was company subsidized or not—
would presumably be prime targets for recruitment by competing rms, just as the experts warned. e
research nding in question does not help defeat the experts’ objection.
E Correct. is explicitly indicates that most rms gain more than they lose from the general practice of
rms paying to train their workers.
e correct answer is E.
550
GMAT® Offi cial Guide 2018
547. Candle Corporation’s television stations are likely to have more income from advertisers than previously. This is because
advertisers prefer to reach people in the 18‐ to 49‐year‐old age group and the number of people in that group watching
Candle television is increasing. Furthermore, among Candle viewers, the percentage of viewers 18 to 49 years old is
increasing.
Which of the following, if true, would most strengthen the argument that Candle Corporation will receive more income from
advertisers?
(A) Advertisers carefully monitor the demographic characteristics of television audiences and purchase advertising time
to reach the audiences they prefer to reach.
(B) Among people over 49 years old, fewer viewers of Candle stations buy products advertised on television than do
viewers of other stations.
(C) There will be increasingly more advertisements on television that are directed at viewers who are over 49 years old.
(D) Candle stations plan to show reruns of television shows during hours when other stations run shows for the rst time.
(E) People 18 to 49 years old generally have less disposable income to spend than do people over 49 years old.
Argument Evaluation
Situation Both the number and the percentage of Candle television viewers who are 18 to 49 years old are
increasing. Advertisers prefer to reach people in this age group.
Reasoning What evidence, when combined with the cited facts, would most support the prediction that Candle
will receive more income from advertisers? e argument assumes that the increasing number and
percentage of Candle viewers in the age group that advertisers prefer to reach will probably
encourage advertisers to spend more on advertising with Candle. is assumption could be
supported by evidence that the advertisers realize that Candle is getting more viewers in that
preferred age range or by evidence that this awareness will in uence the advertisers’ purchase of
advertising time.
A Correct. Advertisers monitoring demographics will probably realize that Candle has increasing numbers
of viewers in their preferred age range. If they purchase advertising to reach viewers in that age range, then
they will probably purchase more advertising time with Candle.
B is gives advertisers less reason to advertise on Candle to reach viewers over 49 years old. Other things
being equal, that makes Candle likely to receive less income from advertisers, not more income.
C Since the percentage of Candle viewers 18 to 49 years old is growing, the percentage over 49 years old is
probably shrinking. is could make advertisers seeking to reach older viewers less inclined to advertise on
Candle even as they increase their overall television advertising.
D Advertisers are not necessarily inclined to purchase more advertising during showings of reruns than
during original airings of television shows and may even be inclined to purchase less advertising during
such showings.
E is gives advertisers less incentive to try to reach audiences between 18 and 49 years old and hence less
reason to purchase advertising on Candle.
e correct answer is A.
551
8.6 Critical Reasoning Answer Explanations
548. A provincial government plans to raise the gasoline tax to give people an incentive to drive less, reducing traf c congestion
in the long term. However, skeptics point out that most people in the province live in areas where cars are the only viable
transportation to jobs and stores and therefore cannot greatly change their driving habits in response to higher gasoline
prices.
In light of the skeptics’ objection, which of the following, if true, would most logically support the prediction that the
government’s plan will achieve its goal of reducing traf c congestion?
(A) The revenue from the tax will be used to make public transportation a viable means of transportation to jobs and
stores for far more people.
(B) The tax will encourage many residents to switch to more fuel‐ef cient cars, reducing air pollution and other problems.
(C) Because gasoline has been underpriced for decades, the province has many neighborhoods where cars are the only
viable means of transportation.
(D) Most residents who cannot greatly change their driving habits could compensate for high gasoline prices by reducing
other expenses.
(E) Traf c congestion is an especially serious problem for people for whom cars are the only viable means of
transportation.
Evaluation of a Plan
Situation A provincial government plans to raise the gasoline tax in order to reduce tra c congestion by
discouraging people from driving. But skeptics point out that most people in the province have no
viable form of transportation other than driving.
Reasoning What would suggest that raising the gasoline tax will reduce tra c congestion even though most people
in the province have no viable form of transportation other than driving? e skeptics point out that
since most people in the province have no way to reach jobs or stores except by car, they will not
be able to reduce their driving much even if the gasoline tax increases. Any evidence that raising
the gasoline tax would reduce tra c congestion despite this obstacle would help to support the
plan in light of the skeptics’ objection.
A Correct. If the tax will fund these public transit improvements, then far more people will have a viable
means of transportation other than driving, undermining the basis of the skeptics’ objection.
B People switching to fuel‐e cient cars would not reduce tra c congestion.
C is essentially only tends to support the skeptics’ objection. Unless the plan somehow helps to alleviate
the necessity of driving (by, for example, making alternative transportation available), the information
provided gives no reason to suppose that the higher costs would signi cantly reduce tra c congestion.
D If residents cannot greatly change their driving habits, then the tax will not reduce tra c congestion.
E is suggests that many residents in the province could bene t if the plan did reduce tra c congestion,
but it does not provide a reason to believe the plan will have that e ect.
e correct answer is A.
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GMAT® Offi cial Guide 2018
549. Editorial: The roof of Northtown’s municipal equipment‐storage building collapsed under the weight of last week’s heavy
snowfall. The building was constructed recently and met local building‐safety codes in every particular, except that the nails
used for attaching roof supports to the building’s columns were of a smaller size than the codes specify for this purpose.
Clearly, this collapse exempli es how even a single, apparently insigni cant departure from safety standards can have
severe consequences.
Which of the following, if true, most seriously weakens the editorial’s argument?
(A) The only other buildings to suffer roof collapses from the weight of the snowfall were older buildings constructed
according to less exacting standards than those in the codes.
(B) The amount of snow that accumulated on the roof of the equipment‐storage building was greater than the predicted
maximum that was used in drawing up the safety codes.
(C) Because the equipment‐storage building was not intended for human occupation, some safety‐code provisions that
would have applied to an of ce building did not apply to it.
(D) The municipality of Northtown itself has the responsibility for ensuring that buildings constructed within its boundaries
meet the provisions of the building‐safety codes.
(E) Because the equipment‐storage building was used for storing snow‐removal equipment, the building was almost
completely empty when the roof collapsed.
Argument Evaluation
Situation e roof of a recently constructed building collapsed under heavy snowfall. e only way the
building did not meet safety standards was that some nails for the roof supports were smaller than
prescribed by the building codes.
Reasoning What would make it less likely that the building’s collapse resulted from a single, apparently minor
departure from safety standards? e building met safety standards except for the size of the nails.
So if the collapse exempli es how a departure from safety standards can have severe consequences,
as the conclusion claims, then the size of the nails had to be responsible for the collapse. us,
evidence that a factor other than the size of the nails could fully account for the collapse would
weaken the argument.
A is suggests that the snow would not have been heavy enough to collapse the roof if the construction had
completely met the safety standards, so it strengthens, rather than weakens, the argument.
B Correct. is suggests that the snow could have collapsed the roof even if the nails had met the safety
standards, thus casting doubt on the assumption that the nails’ inadequacy was responsible for the collapse.
C e claim that the safety requirements for this building were weaker than some others tends slightly to
strengthen, rather than weaken, the hypothesis that the bad consequences resulted partly from a failure to
comply. Even if safety‐code provisions for an equipment‐storage building di er from those for an o ce
building, they may still be adequate to ensure the roof ’s stability.
D e question of who was responsible for ensuring compliance with the safety codes is irrelevant to whether
a failure to comply was responsible for the roof ’s collapse.
E is suggests that the alleged consequences of failing to meet safety standards were less severe than they
could have been, but it is irrelevant to determining the cause of the collapse.
e correct answer is B.
553
8.6 Critical Reasoning Answer Explanations
550. Political theorist: Even with the best spies, area experts, and satellite surveillance, foreign policy assessments can still lack
important information. In such circumstances intuitive judgment is vital. A national leader with such judgment can make
good decisions about foreign policy even when current information is incomplete, since __________.
Which of the following, if true, most logically completes the argument?
(A) the central reason for failure in foreign policy decision making is the absence of critical information
(B) those leaders whose foreign policy decisions have been highly ranked have also been found to have good intuitive
judgment
(C) both intuitive judgment and good information are required for sound decision making
(D) good foreign policy decisions often lead to improved methods of gathering information
(E) intuitive judgment can produce good decisions based on past experience, even when there are important gaps in
current information
Argument Construction
Situation National leaders sometimes must make foreign policy decisions while lacking important
information.
Reasoning What would most help support the claim that a national leader with intuitive judgment can make good
foreign policy decisions without complete information? e word since preceding the blank indicates
that the blank should be lled with a premise supporting the statement immediately before the
blank. So an observation that supports the claim that a national leader with intuitive judgment can
make good foreign policy decisions without complete information would logically complete the
argument.
A is gives us no reason to suppose that intuitive judgment helps national leaders avoid such failures.
B is does not specify who ranked the foreign policy decisions, nor how they determined the rankings, so
it gives us no reason to accept those rankings. For all we know, the anonymous rankers may have used the
dubious rankings they created as the sole evidence for their so-called ndings about which leaders have
good intuitive judgment.
C is implies that intuitive judgment alone is inadequate without good information, so it undermines
rather than supports the claim that national leaders can make good foreign policy decisions with intuitive
judgment while lacking complete information.
D is gives us no reason to suppose that good foreign policy decisions can be made in the rst place by
leaders lacking important information.
E Correct. is suggests that national leaders can make good foreign policy decisions using intuitive
judgment based on their past foreign policy experience, even without complete information about the
current situations they’re facing.
e correct answer is E.
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GMAT® Offi cial Guide 2018
551. During the earliest period of industrialization in Britain, steam engines were more expensive to build and operate than
either windmills or water mills, the other practicable sources of power for factories. Yet despite their signi cant cost
disadvantage, steam‐powered factories were built in large numbers well before technical improvements brought their cost
down. Furthermore, they were built even in regions where geographical conditions permitted the construction of wind‐ and
water‐powered factories close to major markets.
Which of the following, if true, most helps to explain the proliferation of steam‐powered factories during the earliest period
of industrialization in Britain?
(A) In many areas of Britain, there were fewer steam‐powered factories than wind‐ or water‐powered factories in the
earliest period of industrialization.
(B) Unlike wind‐ or water‐powered factories, steam‐powered factories were fueled with coal, which sometimes had to be
transported signi cant distances from the mine to the site of the factory.
(C) It was both dif cult and expensive to convert a factory from wind power or water power to steam power.
(D) In the early period of industrialization, many goods sold in towns and cities could not be mass‐produced in factories.
(E) In Britain, the number of sites where a wind‐ or water‐powered factory could be built was insuf cient to provide for all
of the demand for factory‐produced goods at the time.
Argument Construction
Situation Although steam engines were more expensive than windmills and water mills in early industrial
Britain, many steam‐powered factories were built even in regions where the construction of wind‐
and water‐powered factories was geographically feasible.
Reasoning Why might steam‐powered factories have proliferated despite their cost disadvantage? Early
industrialists would have needed some positive reason to choose steam over less expensive power
sources for their factories. For example, steam engines might have operated faster or more
e ectively than windmills or water mills. Or steam engines might have received government
subsidies. Or conditions restricting the number or locations of windmills and water mills might
have forced industrialists to use steam power instead.
A is suggests that the steam‐powered factories did not initially proliferate as widely as they might have,
but it does not explain why they proliferated to the extent that they did.
B e inconvenience of transporting coal for steam‐powered factories would have made those factories less
likely to proliferate, not more likely.
C e di culty of converting factories to steam power would have made steam‐powered factories less likely
to proliferate, not more likely.
D e technological inability to mass‐produce popular products in factories would have made factories in
general less likely to proliferate, including steam‐powered factories.
E Correct. e inadequate number of sites for wind‐ and water‐powered factories might have encouraged
early industrialists to build steam‐powered factories instead, since the high demand for factory‐produced
goods could have made these factories pro table despite their cost disadvantage.
e correct answer is E.
555
8.6 Critical Reasoning Answer Explanations
552. Snowmaking machines work by spraying a mist that freezes immediately on contact with cold air. Because the sudden
freezing kills bacteria, QuickFreeze is planning to market a wastewater puri cation system that works on the same principle.
The process works only when temperatures are cold, however, so municipalities using it will still need to maintain a
conventional system.
Which of the following, if true, provides the strongest grounds for a prediction that municipalities will buy QuickFreeze’s
puri cation system despite the need to maintain a conventional puri cation system as well?
(A) Bacteria are not the only impurities that must be removed from wastewater.
(B) Many municipalities have old wastewater puri cation systems that need to be replaced.
(C) Conventional wastewater puri cation systems have not been fully successful in killing bacteria at cold temperatures.
(D) During times of warm weather, when it is not in use, QuickFreeze’s puri cation system requires relatively little
maintenance.
(E) Places where the winters are cold rarely have a problem of water shortage.
Evaluation of a Plan
Situation QuickFreeze is planning to market wastewater puri cation systems that work by spraying a mist
that freezes on contact with cold air. e sudden freezing kills bacteria. Because the system works
only at cold temperatures, municipalities using it will still need to maintain a conventional system.
Reasoning Which statement provides the strongest grounds for thinking that at least some municipalities will buy the
puri cation system despite the need to maintain a conventional puri cation system as well? e passage
tells us why a municipality using a QuickFreeze wastewater puri cation system would still need
a conventional system. But why would a municipality want the QuickFreeze system in addition
to a conventional system? If conventional systems are not fully e ective at cold temperatures, the
QuickFreeze system would allow municipalities that sometimes experience cold temperatures to
purify their wastewater more e ectively.
A ere is no basis in the passage for determining whether the QuickFreeze system will help remove
impurities other than bacteria from wastewater. If it does not, this answer choice implies that the
QuickFreeze system would not be su cient for purifying wastewater. is would actually undermine the
prediction.
B e passage states that municipalities using the QuickFreeze system would still need a conventional
system. us, the old conventional wastewater systems would still need to be replaced with new
conventional systems. is answer choice provides no reason to think municipalities would buy the
QuickFreeze system.
C Correct. is statement, if true, would strengthen the prediction, because it provides a valid reason why
the QuickFreeze system could be needed alongside conventional ones: it is more e ective in cold weather.
D Although this claim does undercut one reason for thinking municipalities might not be likely to purchase
the QuickFreeze system, it provides little reason to think that they will purchase such a system. Perhaps in
times of cold weather, the QuickFreeze system is very expensive to maintain.
E e issue of whether or not there are water shortages in places where winters are cold is not directly
relevant. If conventional wastewater systems are su cient to purify water in such places, municipalities
would not need the QuickFreeze system (as they would still need to maintain a conventional puri cation
system).
e correct answer is C.
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GMAT® Offi cial Guide 2018
553. Suncorp, a new corporation with limited funds, has been clearing large sections of the tropical Amazon forest for cattle
ranching. This practice continues even though greater pro ts can be made from rubber tapping, which does not destroy the
forest, than from cattle ranching, which does destroy the forest.
Which of the following, if true, most helps to explain why Suncorp has been pursuing the less pro table of the two economic
activities mentioned above?
(A) The soil of the Amazon forest is very rich in nutrients that are important in the development of grazing lands.
(B) Cattle‐ranching operations that are located in tropical climates are more pro table than cattle‐ranching operations that
are located in cold‐weather climates.
(C) In certain districts, pro ts made from cattle ranching are more heavily taxed than pro ts made from any other
industry.
(D) Some of the cattle that are raised on land cleared in the Amazon are killed by wildcats.
(E) The amount of money required to begin a rubber‐tapping operation is twice as high as the amount needed to begin a
cattle ranch.
Argument Construction
Situation Suncorp is a new corporation with limited funds. It has been clearing large sections of the tropical
Amazon forest for ranching, even though rubber‐tapping would be more pro table.
Reasoning What would explain why Suncorp is clearing sections of the rain forest for ranching, even though rubber
tapping would be more pro table? Because Suncorp has limited funds, if rubber tapping has much
higher start‐up costs, Suncorp might not have enough money to start rubber‐tapping operations.
If cattle ranching has much lower start‐up costs than rubber tapping, Suncorp might be able to
a ord such an operation.
A is statement gives a reason why cattle ranching in the Amazon might be more pro table than one might
otherwise think it would be. However, we already know from the passage that rubber tapping would be
more pro table than cattle ranching. So, this answer choice does not help explain why cattle ranching
might be preferable to rubber tapping.
B e comparison between the pro tableness of cattle ranching in tropical climates and in cold‐weather
climates is irrelevant. e passage only covers cattle ranching in the tropical Amazon forest. is answer
choice would at most explain why Suncorp is undertaking cattle ranching in the Amazon rather than in
some cold‐weather location.
C is statement makes what needs to be explained harder to understand, for it indicates that cattle ranching
in the Amazon might be less pro table than one would otherwise think.
D Like answer choice (C), this statement indicates a disadvantage of cattle ranching in the Amazon. So, it
does not explain why cattle ranching would be preferred to some other economic activity.
E Correct. Because it costs less to begin cattle ranching than it does to begin rubber tapping, Suncorp—
which has limited funds—would have a reason to pursue cattle ranching over a potentially more pro table
activity.
e correct answer is E.
557
8.6 Critical Reasoning Answer Explanations
554. Archaeologists use technology to analyze ancient sites. It is likely that this technology will advance considerably in the near
future, allowing archaeologists to gather more information than is currently possible. If they study certain sites now, they
risk contaminating or compromising them for future studies. Therefore, in order to maximize the potential for gathering
knowledge in the long run, a team of archaeologists plans to delay the examination of a newly excavated site.
Which of the following would be most useful to investigate for the purpose of evaluating the plan’s prospects for achieving
its goal?
(A) Whether any of the contents of the site will signi cantly deteriorate before the anticipated technology is available
(B) Whether there will continue to be improvements on the relevant technology
(C) Whether the team can study a site other than the newly excavated site for the time being
(D) Whether the site was inhabited by a very ancient culture
(E) Whether the anticipated technology will damage objects under study
Evaluation of a Plan
Situation To avoid prematurely compromising a newly excavated site, an archaeological team plans to
postpone examining it until more advanced technology is developed that will let them gather more
information from it. eir goal is to maximize the potential for gathering knowledge.
Reasoning What would be most helpful to investigate in order to assess how likely it is that delaying examination of
the site will maximize the potential for gathering knowledge from it? In order to maximize (or even
increase) the potential for gathering knowledge from the site by delaying its examination, the risk
of compromising the site by examining it now has to be greater than the risk that the site will
be compromised as much or more by delaying the examination. e delay might also increase
the risk that the site will never be examined at all—for example, the team might lose its funding
while it delays, or changes in local political conditions might prevent the site’s future examination.
Investigating any of these risks could be helpful in assessing the likelihood that the team’s plan will
achieve its goal.
A Correct. If any of the site’s contents will signi cantly deteriorate before the technology becomes available,
that could reduce the ability to gather future information from the site even more than examining and
compromising the site now would.
B e passage already tells us that it is likely the technology will advance considerably in the near future.
Given this information, further inquiry into whether there will be any ongoing (perhaps minor)
improvements is somewhat redundant and probably of minimal value with respect to evaluating the plan’s
likelihood of success.
C Even if the team can study a second site in the meanwhile, they might maximize the overall potential
for gathering knowledge by delaying the examination of either site, both sites, or neither site until more
advanced technology is available.
D e age of the culture that inhabited the site is irrelevant to assessing the risks of delaying the site’s
examination until more advanced technology is available.
E Even if the anticipated technology will damage or destroy the objects under study, it might still maximize
the amount of knowledge that can be gathered from those objects. Without any comparison between the
damage risk that would be incurred by proceeding with the current technology and the damage risk that
would be incurred by waiting, the mere fact that some damage would occur is irrelevant.
e correct answer is A.
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GMAT® Offi cial Guide 2018
555. A newly discovered painting seems to be the work of one of two seventeenth‐century artists, either the northern German
Johannes Drechen or the Frenchman Louis Birelle, who sometimes painted in the same style as Drechen. Analysis of the
carved picture frame, which has been identi ed as the painting’s original seventeenth‐century frame, showed that it is made
of wood found widely in northern Germany at the time, but rare in the part of France where Birelle lived. This shows that the
painting is most likely the work of Drechen.
Which of the following is an assumption that the argument requires?
(A) The frame was made from wood local to the region where the picture was painted.
(B) Drechen is unlikely to have ever visited the home region of Birelle in France.
(C) Sometimes a painting so resembles others of its era that no expert is able to con dently decide who painted it.
(D) The painter of the picture chose the frame for the picture.
(E) The carving style of the picture frame is not typical of any speci c region of Europe.
Argument Construction
Situation e original frame of a seventeenth‐century painting that seems to be by either the northern
German Johannes Drechen or the Frenchman Louis Birelle is made of a type of wood much more
common in northern Germany than in France, suggesting that Drechen was the painter.
Reasoning What must be true in order for the facts presented to support the conclusion that the painting is by
Drechen? e argument is that in the seventeenth century, the type of wood in the frame was more
common in northern Germany where Drechen was from than in France where Birelle was from,
so probably Drechen painted the picture. In order for this inference to be plausible, the argument
must implicitly assume that the frame’s wood was from the same region the painter was from. And
in order to justify this assumed connection between the wood and the region the painter was from,
the argument must also assume that the painter painted the picture in that region.
A Correct. If the frame were not made of wood local to the region where the picture was painted, or if that
region in turn were not where the painter was from, then the cited fact about where the wood was more
common would be irrelevant to the conclusion about who painted the picture.
B e argument is compatible with the plausible hypothesis that Drechen visited France at some point
during his lifetime but did not frame this or any painting with French wood.
C Even if experts always felt con dent in deciding who painted any picture, examining the wood in the
picture frame might help them decide correctly.
D e argument is compatible with the plausible hypothesis that the picture was sold to a local customer
who then chose a frame of local wood.
E e argument would be even stronger if this were false and the carving style of the frame were typical of
northern Germany speci cally.
e correct answer is A.
559
8.6 Critical Reasoning Answer Explanations
556. Beginning in 1966 all new cars sold in Morodia were required to have safety belts and power steering. Previously, most
cars in Morodia were without these features. Safety belts help to prevent injuries in collisions, and power steering helps to
avoid collisions in the rst place. But even though in 1966 one-seventh of the cars in Morodia were replaced with new cars,
the number of car collisions and collision-related injuries did not decline.
Which of the following, if true about Morodia, most helps to explain why the number of collisions and collision-related injuries in
Morodia failed to decline in 1966?
(A) Because of a driver-education campaign, most drivers and passengers in cars that did have safety belts used them in
1966.
(B) Most of the new cars bought in 1966 were bought in the months of January and February.
(C) In 1965, substantially more than one-seventh of the cars in Morodia were replaced with new cars.
(D) An excessive reliance on the new safety features led many owners of new cars to drive less cautiously in 1966 than
before.
(E) The seat belts and power steering put into new cars sold in 1966 had to undergo strict quality-control inspections by
manufacturers, whether the cars were manufactured in Morodia or not.
Argument Construction
Situation Starting in 1966, new cars sold in Morodia were required to have safety belts and power steering.
But the numbers of car collisions and collision-related injuries did not decline that year.
Reasoning What could explain why the newly required safety features did not reduce the numbers of collisions and
collision-related injuries in 1966? e passage says that power steering helps to prevent collisions
and that safety belts help to prevent collision-related injuries. Since most Morodian cars
previously lacked these features, and one-seventh of them were replaced with new cars in 1966,
the proportion of cars with these features must have increased that year. is should have reduced
the numbers of collisions and collision-related injuries unless some other factor counteracted the
reductions. Evidence of any such countervailing factor would help to explain why the numbers did
not decrease.
A Increased usage of safety belts should have reduced the number of collision-related injuries, so it would not
help explain why this number did not decrease.
B If the new cars bought in 1966 were mostly purchased early in the year, the increased proportion of cars
with the newly required safety features should have started more signi cantly reducing the numbers of
collisions and collision-related injuries early in the year, producing greater reductions for the year as a
whole.
C However, many cars were replaced in the year before the safety features were required, in 1966 the
replacement of one-seventh of all Morodian cars should still have increased the overall proportion of
Morodian cars with the safety features and thus reduced the numbers of collisions and collision-related
injuries.
D Correct. If many owners of the cars with the new safety features drove less cautiously, their recklessness
could have increased the overall numbers of collisions and collision-related injuries despite any bene ts
from the safety features.
E Strict quality-control inspections should have made the safety features more reliable, further reducing the
numbers of collisions and collision-related injuries.
e correct answer is D.
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557. In order to reduce the number of items damaged while in transit to customers, packaging consultants recommended
that the TrueSave mail‐order company increase the amount of packing material so as to ll any empty spaces in its
cartons. Accordingly, TrueSave of cials instructed the company’s packers to use more packing material than before, and
the packers zealously acted on these instructions and used as much as they could. Nevertheless, customer reports of
damaged items rose somewhat.
Which of the following, if true, most helps to explain why acting on the consultants’ recommendation failed to achieve its
goal?
(A) The change in packing policy led to an increase in expenditure on packing material and labor.
(B) When packing material is compressed too densely, it loses some of its capacity to absorb shock.
(C) The amount of packing material used in a carton does not signi cantly in uence the ease with which a customer can
unpack the package.
(D) Most of the goods that TrueSave ships are electronic products that are highly vulnerable to being damaged in transit.
(E) TrueSave has lost some of its regular customers as a result of the high number of damaged items they received.
Evaluation of a Plan
Situation Mail‐order company TrueSave wants to reduce the number of items damaged while in transit to
customers. Packaging consultants recommended that to achieve this goal, the company should use
more packing material to ll empty spaces in its cartons. e company’s packers began using as
much packing material as they could, yet reports of damaged items rose rather than fell.
Reasoning What would help explain why the company’s acting on the recommendation did not achieve its goal? e
recommendation involved increasing the amount of packing material, so there must have been
something about that increase that led to more damage. More damage would be likely to result if
stu ng more packing material into shipping boxes made the packaging less e ective.
A An increase in expenditure on packing material and labor might a ect the company’s pro tability, but it
would have no e ect on whether items were damaged in transit.
B Correct. is statement adequately explains why more items, rather than fewer, were damaged in transit.
C If customers were able to remove their items just as easily from boxes lled with more packing material
as from boxes using less packing material, the items would be una ected by an increase in the amount of
packing material used.
D e kind of goods TrueSave ships most frequently is not relevant to the question of why increasing the
amount of packing material failed to reduce the number of items damaged in transit, since they most likely
shipped this same kind of goods both before and after making the recommended change.
E e loss of regular customers helps explain why TrueSave turned to the packaging consultants for help,
but it does not help explain why those consultants’ recommendation failed to reduce the number of items
damaged in transit.
e correct answer is B.
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8.6 Critical Reasoning Answer Explanations
558. Parland’s alligator population has been declining in recent years, primarily because of hunting. Alligators prey heavily on
a species of freshwater sh that is highly valued as food by Parlanders, who had hoped that the decline in the alligator
population would lead to an increase in the numbers of these sh available for human consumption. Yet the population of
this sh species has also declined, even though the annual number caught for human consumption has not increased.
Which of the following, if true, most helps to explain the decline in the population of the sh species?
(A) The decline in the alligator population has meant that shers can work in some parts of lakes and rivers that were
formerly too dangerous.
(B) Over the last few years, Parland’s commercial shing enterprises have increased the number of shing boats they
use.
(C) The main predator of these sh is another species of sh on which alligators also prey.
(D) Many Parlanders who hunt alligators do so because of the high market price of alligator skins, not because of the
threat alligators pose to the sh population.
(E) In several neighboring countries through which Parland’s rivers also ow, alligators are at risk of extinction as a result
of extensive hunting.
Argument Construction
Situation Due to hunting, Parland’s alligator population has been declining. Parlanders had hoped that
the population of a certain prized species of freshwater sh that alligators prey on would have
increased as a result, but the population of this freshwater sh has actually declined.
Reasoning What would explain why the population of the freshwater species has declined? Suppose alligators prey
not only on the prized freshwater sh but also on another species of sh that is the main predator
of those sh. If there are fewer alligators to prey on the predator sh, there may well be more of
the predator sh. An increase in the population of the predator sh could help explain why the
population of the prized freshwater sh has declined: there are now more of the predator sh
around to prey on them.
A ough this statement suggests that the population of the prized sh species may have declined due to
their being caught in greater numbers by shers, the passage tells us that the number of these sh caught
for human consumption has not increased. erefore, this statement cannot explain the species’ decline in
population.
B e passage tells us that the number of sh caught for human consumption has not increased. is answer
choice does not provide any explanation for why the population of these sh has declined.
C Correct. Since alligators prey on the predator sh, a decline in the alligator population could result in an
increase in the population of the predator sh, which could lead to an increase in nonhuman consumption
of the prized freshwater sh.
D We already know from the passage that hunting has led to a decline in the population of alligators. It is
irrelevant what motivated the hunting of alligators.
E e fact that alligators are at risk of extinction due to hunting in neighboring countries does not help
explain why the prized freshwater sh species is declining in population. If it is puzzling why the sh
population is declining despite the reduction in Parland’s alligator population, it would be just as puzzling
if the alligator population elsewhere was declining.
e correct answer is C.
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559. A certain automaker aims to increase its market share by deeply discounting its vehicles’ prices for the next several
months. The discounts will cut into pro ts, but because they will be heavily advertised the manufacturer hopes that they
will attract buyers away from rival manufacturers’ cars. In the longer term, the automaker envisions that customers initially
attracted by the discounts may become loyal customers.
In assessing the plan’s chances of achieving its aim, it would be most useful to know which of the following?
(A) Whether the automaker’s competitors are likely to respond by offering deep discounts on their own products
(B) Whether the advertisements will be created by the manufacturer’s current advertising agency
(C) Whether some of the automaker’s models will be more deeply discounted than others
(D) Whether the automaker will be able to cut costs suf ciently to maintain pro t margins even when the discounts are in
effect
(E) Whether an alternative strategy might enable the automaker to enhance its pro tability while holding a constant or
diminishing share of the market
Evaluation of a Plan
Situation An automaker is planning to o er deep discounts on its vehicles’ prices in order to increase its
market share. e automaker’s pro t margins will be reduced by this action. By advertising the
discounts, the automaker hopes to attract customers who might otherwise be inclined to buy rival
manufacturers’ cars. ese customers would ideally then develop loyalty to the automaker’s cars.
Reasoning What would it be most useful to know in assessing whether o ering deep discounts will enable the
automaker to increase its market share? To achieve an increase in market share, the automaker would
have to take customers away from other automakers. Under what circumstances would other
automakers be able to retain their customers, if those customers are more likely to purchase cars
from automakers that o er deep discounts (and then remain loyal to those automakers)? e other
automakers might try to retain their customers by matching the discounts. us it would be useful
to know whether the other automakers would indeed o er such discounts.
A Correct. If the answer to this question were yes, the plan would probably not achieve its aim of increasing
market share. If the answer were no, the plan would have a good chance of succeeding.
B Since there is no information about the e ectiveness of the automaker’s current advertising, it would not
be useful to know whether the same advertising agency will produce the ads publicizing the discount.
C Knowing whether some models will be more deeply discounted than others might help in assessing
which of the automaker’s models will sell best, but it would not help in assessing the overall chance of the
automaker increasing its market share.
D e discounts the automaker plans to o er will cut into pro ts, according to the information given, so
the question of whether the automaker can maintain pro t margins while the discounts are in e ect has
already been answered.
E While it might be useful to the automaker to know about alternative strategies, such knowledge does not
help in assessing the likelihood that the plan under discussion will achieve its aim.
e correct answer is A.
563
8.6 Critical Reasoning Answer Explanations
560. In virtually any industry, technological improvements increase labor productivity, which is the output of goods and services
per person‐hour worked. In Parland’s industries, labor productivity is signi cantly higher than it is in Vergia’s industries.
Clearly, therefore, Parland’s industries must, on the whole, be further advanced technologically than Vergia’s are.
The argument is most vulnerable to which of the following criticisms?
(A) It offers a conclusion that is no more than a paraphrase of one of the pieces of information provided in its support.
(B) It presents as evidence in support of a claim information that is inconsistent with other evidence presented in support
of the same claim.
(C) It takes one possible cause of a condition to be the actual cause of that condition without considering any other
possible causes.
(D) It takes a condition to be the effect of something that happened only after the condition already existed.
(E) It makes a distinction that presupposes the truth of the conclusion that is to be established.
Argument Evaluation
Situation Technological improvements in nearly every industry increase labor productivity, which is the
output of goods and services per person‐hour worked. Because labor productivity is signi cantly
higher in Parland than Vergia, Parland’s industries are, in general, more technologically advanced
than Vergia’s.
Reasoning To which criticism is the argument most vulnerable? ough one factor, such as technological
advancements, may lead to greater labor productivity, it may not be the only such factor, or even
a necessary factor, leading to great labor productivity. erefore, the mere fact that one region’s
labor is more productive than another’s is not su cient to establish that the former region is more
technologically advanced than the latter region is.
A e conclusion is not merely a paraphrase of the pieces of information provided in its support. Indeed, the
problem with the argument is that the conclusion goes too far beyond what the premises merit.
B e premises of the argument are not inconsistent with one another.
C Correct. is accurately describes the aw in the argument because the reasons given in the argument
for its conclusion would be good reasons only if there were no other plausible explanations for Parland’s
greater labor productivity.
D e argument does not mention how long Parland has had more productive labor, or when technological
improvements would have occurred.
E Neither of the premises contains anything that presupposes the conclusion to be true.
e correct answer is C.
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561. Chaco Canyon, a settlement of the ancient Anasazi culture in North America, had massive buildings. It must have been a
major Anasazi center. Analysis of wood samples shows that some of the timber for the buildings came from the Chuska
and San Mateo mountains, 50 miles from Chaco Canyon. Only a major cultural center would have the organizational
power to import timber from 50 miles away.
In the argument given, the two portions in boldface play which of the following roles?
(A) The rst is a premise used to support the argument’s main conclusion; the second is the argument’s main conclusion.
(B) The rst is the argument’s main conclusion; the second is a premise used to support that conclusion.
(C) The rst is one of two premises used to support the argument’s main conclusion; the second is the other of those two
premises.
(D) The rst is a premise used to support the argument’s main conclusion; the second is a premise used to support
another conclusion drawn in the argument.
(E) The rst is inferred from another statement in the argument; the second is inferred from the rst.
Argument Construction
Situation e ancient Anasazi settlement at Chaco Canyon had massive buildings, for which some of the
timber came from mountains 50 miles away.
Reasoning What roles do the statement that Chaco Canyon must have been a major Anasazi center and the statement
that only a major center would have the organizational power to import timber from 50 miles away play
in the argument? e rst and third sentences in the passage are both factual observations. Since
no further support is provided for either of them, neither can be a conclusion in the argument.
e fourth sentence is a speculative generalization about major cultural centers. None of the other
statements gives us any reason to think this generalization is true, so it cannot be a conclusion in
the argument, either. However, the third and fourth sentences together imply that Chaco Canyon
was a major cultural center, and the rst sentence indicates that it was Anasazi. So together, the
rst, third, and fourth sentences all support the claim that Chaco Canyon was a major Anasazi
cultural center and thus more generally a major Anasazi center, as the second sentence asserts.
erefore, the rst, third, and fourth sentences are all premises that jointly support the second
sentence as a conclusion.
A As explained above, the rst boldface sentence is a conclusion supported by the latter, not the other way
around.
B Correct. As explained above, the rst boldface sentence is the argument’s only stated conclusion, and in
that sense its main conclusion, while all the other sentences are premises used to support it.
C As explained above, the rst boldface sentence is the argument’s conclusion, not a premise used to support
the conclusion.
D As explained above, the rst boldface sentence is the argument’s only stated conclusion, and there is no
reason to suppose that the argument is intended to lead to any other tacit conclusion that the second
boldface sentence is intended to support.
E As explained above, the rst boldface sentence is inferred from the three other statements in the argument
together, not from any one of them alone. e second boldface sentence is a speculative generalization that
cannot be, and is not meant to be, inferred from the former or from any other statement in the argument.
e correct answer is B.
565
8.6 Critical Reasoning Answer Explanations
562. The Maxilux car company’s design for its new luxury model, the Max 100, included a special design for the tires that was
intended to complement the model’s image. The winning bid for supplying these tires was submitted by Rubco. Analysts
concluded that the bid would only just cover Rubco’s costs on the tires, but Rubco executives claim that winning the bid will
actually make a pro t for the company.
Which of the following, if true, most strongly justi es the claim made by Rubco’s executives?
(A) In any Maxilux model, the spare tire is exactly the same make and model as the tires that are mounted on the wheels.
(B) Rubco holds exclusive contracts to supply Maxilux with the tires for a number of other models made by Maxilux.
(C) The production facilities for the Max 100 and those for the tires to be supplied by Rubco are located very near each
other.
(D) When people who have purchased a carefully designed luxury automobile need to replace a worn part of it, they
almost invariably replace it with a part of exactly the same make and type.
(E) When Maxilux awarded the tire contract to Rubco, the only criterion on which Rubco’s bid was clearly ahead of its
competitors’ bids was price.
Argument Construction
Situation Rubco won a bid for supplying tires for the Max 100, a new luxury model by Maxilux. e bid
would barely cover the cost of the tires, but Rubco executives claim that winning the bid will be
pro table.
Reasoning What would support the executives’ claim? Rubco is not expected to make a pro t from supplying
the tires for the new cars, so we must look for some other way that Rubco could derive a pro t
as a result of winning the bid. If by winning the bid Rubco created an inevitable market for itself
in replacement tires—on which Rubco could earn a pro t—then the executives’ claim may be
justi ed.
A We have already been told that the bid is expected to barely cover the costs of supplying the tires on the
new cars, so the analysts mentioned in the passage have presumably already taken into account that there
is a spare tire supplied for the Max 100.
B If winning the bid led Rubco to win more exclusive contracts with the Maxilux, that might help support
the executives’ claim. But this statement indicates only that Rubco already has several exclusive contracts to
supply Maxilux with tires, not that winning the bid has led to, or will lead to, more such contracts, which is
what would be needed.
C As in answer choice (A), this is relevant to the costs of supplying the tires for the Max 100, but presumably
this was taken into account by the analysts when they concluded that the bid would barely cover Rubco’s
costs on the tires.
D Correct. is indicates that by winning the bid Rubco has created a way to pro t from the contract with
Maxilux, speci cally, by creating a market for replacement tires.
E is is likely one of the reasons that Rubco’s bid only just covers Rubco’s costs on the tires; it does nothing
to justify the executives’ claims that the bid will lead to a pro t for Rubco.
e correct answer is D.
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563. Which of the following most logically completes the passage?
Most bicycle helmets provide good protection for the top and back of the head, but little or no protection for the temple
regions on the sides of the head. A study of head injuries resulting from bicycle accidents showed that a large proportion
were caused by blows to the temple area. Therefore, if bicycle helmets protected this area, the risk of serious head injury in
bicycle accidents would be greatly reduced, especially since ________.
(A) among the bicyclists included in the study’s sample of head injuries, only a very small proportion had been wearing a
helmet at the time of their accident
(B) even those bicyclists who regularly wear helmets have a poor understanding of the degree and kind of protection that
helmets afford
(C) a helmet that included protection for the temples would have to be somewhat larger and heavier than current helmets
(D) the bone in the temple area is relatively thin and impacts in that area are thus very likely to cause brain injury
(E) bicyclists generally land on their arm or shoulder when they fall to the side, which reduces the likelihood of severe
impacts on the side of the head
Argument Construction
Situation Bicycle helmets protect the top and back of the head, but not the sides or temples. A study found
that a large proportion of head injuries caused by biking accidents were caused by blows to the
temple area.
Reasoning Why would the risk of serious head injury in bicycle accidents be greatly reduced if bicycle helmets protected
the temple regions? If for some reason a serious head injury is particularly likely when there is
impact to the temple area, then bicycle helmets that protect that area would be apt to reduce the
number of serious head injuries from bicycle accidents. One such reason is that the bone in the
temple area is relatively thin.
A is point is irrelevant because it gives us no information about the seriousness or the likelihood of injuries
due to impact to the temple area.
B Whether bicyclists who regularly wear helmets have a good understanding of what protection their
helmets a ord is not relevant as to whether serious head injuries are particularly likely to occur from
impact to the temple area.
C is point is relevant only to what a helmet that protected the temple area would be like, not to the
seriousness of injuries resulting from impact to that area. If anything, this point counts as a reason against
the conclusion, not for it. If such helmets are heavier and larger, they may be used less than they otherwise
would be. If fewer helmets are used, then improvements to helmet design will have less of an e ect in
reducing serious head injuries.
D Correct. is statement provides a reason why the temple area of the rider’s head needs protection:
impacts to this area are very likely to cause brain injuries.
E is is largely irrelevant. Even if it suggests that head injuries do not generally result from bicyclists falling
to the side, it does not indicate that such injuries are rare or that there is not great risk of serious injury in
those cases in which there is impact to the temple area.
e correct answer is D.
567
8.6 Critical Reasoning Answer Explanations
564. Which of the following most logically completes the argument?
In a typical year, Innovair’s airplanes are involved in 35 collisions while parked or being towed in airports, with a resulting
yearly cost of $1,000,000 for repairs.
To reduce the frequency of ground collisions, Innovair will begin giving its ground crews additional training, at an annual cost
of $500,000. Although this will cut the number of ground collisions by about half at best, the drop in repair costs can be
expected to be much greater, since __________.
(A) most ground collisions happen when ground crews are rushing to minimize the time a delayed airplane spends on the
ground
(B) a ground collision typically occurs when there are no passengers on the airplane
(C) the additional training will focus on helping ground crews avoid those kinds of ground collisions that cause the most
costly damage
(D) the $500,000 cost gure for the additional training of ground crews includes the wages that those crews will earn
during the time spent in actual training
(E) most ground collisions have been caused by the least experienced ground‐crew members
Evaluation of a Plan
Situation An airline will give its ground crews additional training to reduce the frequency of the collisions
its airplanes are involved in while parked or being towed in airports.
Reasoning What premise would most logically support the conclusion that the additional training will reduce repair
costs from ground collisions much more than it reduces the number of such collisions? e key word since
before the blank shows that the argument should be completed with a premise that supports the
preceding claim that the drop in repair costs can be expected to be much greater . A suitable premise
might provide evidence that the training will disproportionately help to prevent the ground
collisions that result in the higher repair costs as opposed to the less serious collisions that result in
lower repair costs.
A We are given no reason to believe that the additional training would a ect how much ground crews rush
to minimize delays.
B e number of passengers is not clearly relevant to the repair costs resulting from a ground collision and in
any case would not be a ected by additional ground crew training.
C Correct. If the training especially helps the ground crews avoid those kinds of collisions that cause the
most costly damage, then it will probably reduce repair costs even more than it reduces the number of
collisions.
D Whether the cited expense for training includes wages is irrelevant to whether the training will reduce
repair costs more than it reduces the number of collisions.
E is suggests that the additional training may help reduce the number of collisions, not that it will reduce
repair costs more than it reduces the number of collisions.
e correct answer is C.
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565. Hunter: Many people blame hunters alone for the decline in Greenrock National Forest’s deer population over
the past ten years. Yet clearly, black bears have also played an important role in this decline. In the past ten years, the
forest’s protected black bear population has risen sharply, and examination of black bears found dead in the forest during
the deer hunting season showed that a number of them had recently fed on deer.
In the hunter’s argument, the portion in boldface plays which of the following roles?
(A) It is the main conclusion of the argument.
(B) It is a nding that the argument seeks to explain.
(C) It is an explanation that the argument concludes is correct.
(D) It provides evidence in support of the main conclusion of the argument.
(E) It introduces a judgment that the argument opposes.
Argument Construction
Situation e hunter claims that hunters have been identi ed by many people as the sole cause of the
decline in Greenrock National Forest’s deer population. But the hunter argues that black bears
have also contributed to the deer population decline. Black bears are protected and have increased
in number, and they have been found to have fed recently on deer.
Reasoning What role in the argument is played by the hunter’s statement that many people blame hunters alone for
the decline in the national forest’s deer population? In this statement, the hunter claims that many
people have judged hunters responsible for the decline. e hunter then goes on to o er evidence
supporting a di erent judgment: that hunters are not solely responsible, but that black bears are
also to blame.
A e hunter’s main conclusion is that black bears have also contributed to the decline in the deer
population.
B e argument seeks to o er a reason for the nding that the deer population has declined, not the nding
that people blame hunters for that decline.
C e hunter does not conclude that blaming hunters for the decline in the deer population is correct; rather,
the hunter suggests that black bears should also be blamed.
D e hunter believes that hunters are not solely responsible for the decline in the deer population, so
people’s suggestion that they are responsible does not support the hunter’s main conclusion.
E Correct. e boldfaced statement cites a judgment that the hunter attributes to many people, and that
the hunter argues is incorrect. e hunter opposes the judgment that hunters alone are responsible for the
decline in the deer population.
e correct answer is E.
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8.6 Critical Reasoning Answer Explanations
566. Many agriculturally intensive areas of the world are beginning to encounter water scarcity problems. As a result, many
farmers in these areas are likely to reduce their output as the water supply they need in order to maintain production
shrinks. However, one group of farmers in such a region plans to increase their production by implementing techniques for
water conservation.
Which of the following, if true, would most strongly support the prediction that the group’s plan will succeed?
(A) Farmers who can gain a larger share of the food market in their regions will be better positioned to control more
water resources.
(B) Most agricultural practices in areas with water shortages are water‐intensive.
(C) Other regions of the world not facing water shortages are likely to make up for the reduction in agricultural output.
(D) Demand for agricultural products in the group’s region is not expected to decline.
(E) More than half the water used for agriculture in the farmers’ region is lost to evaporation or leakage from irrigation
channels.
Evaluation of a Plan
Situation Farmers in many agriculturally intensive regions will probably reduce their output because the
regions’ water supplies are dwindling, but one group of farmers in such a region plans to use water
conservation techniques to increase their output.
Reasoning What would provide evidence that water conservation techniques will help the farmers increase
production despite their region’s dwindling water supplies? In order for the water conservation
techniques to be e ective, they must result in signi cantly more water becoming available for the
farmers to use. Because overall supplies are shrinking, rather than growing, that can only happen
if the farmers are currently losing or wasting a great deal of water in ways that could be prevented
with water conservation techniques.
A is suggests an advantage the farmers will gain if their water conservation plan enables them to increase
production, but it provides no evidence that the plan actually will enable them to increase production.
B is suggests that the plan would have to yield quite a lot of conserved water in order for the farmers to
increase production, but it o ers no evidence that the plan will do so. us, it provides some reason to
question whether the plan will succeed.
C Whether regions without water shortages will increase production is not directly relevant to the question
of whether a particular measure would lead to increased production in one region that does have a water
shortage.
D is has some slight, indirect relevance to the question of whether the farmers’ plan will succeed: it
suggests that if the farmers do manage to increase production, they will continue to have a market for what
they produce. However, it does not address the issue of whether they will be able to increase production.
Furthermore, even if demand for agricultural products in the group’s region were expected to decline, it
could still remain high enough to support the farmers’ increased output from their water conservation plan.
E Correct. is suggests that the farmers are losing a lot of water in ways that the water conservation
techniques might prevent, so it provides evidence that employing some such techniques could enable the
farmers to save enough water to increase their output.
e correct answer is E.
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567. Physician: The hormone melatonin has shown promise as a medication for sleep disorders when taken in synthesized form.
Because the long‐term side effects of synthetic melatonin are unknown, however, I cannot recommend its use at this time.
Patient: Your position is inconsistent with your usual practice. You prescribe many medications that you know have serious
side effects, so concern about side effects cannot be the real reason you will not prescribe melatonin.
The patient’s argument is awed because it fails to consider that
(A) the side effects of synthetic melatonin might be different from those of naturally produced melatonin
(B) it is possible that the physician does not believe that melatonin has been conclusively shown to be effective
(C) sleep disorders, if left untreated, might lead to serious medical complications
(D) the side effects of a medication can take some time to manifest themselves
(E) known risks can be weighed against known bene ts, but unknown risks cannot
Argument Evaluation
Situation e physician refuses to prescribe synthetic melatonin to treat sleep disorders despite this
medication’s promise. e reason the physician o ers for this refusal is that the long‐term side
e ects of synthetic melatonin are unknown. e patient responds that because the physician
prescribes other medications that are known to have serious side e ects, it cannot be a concern
for synthetic melatonin’s side e ects that is prompting the physician’s refusal to prescribe that
medication.
Reasoning What does the patient’s argument fail to consider? e patient says that the inconsistency in the
physician’s position lies in the physician’s unwillingness to prescribe synthetic melatonin coupled
with a willingness to prescribe other medications that are known to have serious side e ects. But
notice that the physician does not say that synthetic melatonin has serious side e ects; rather, the
physician points out that the long‐term side e ects of synthetic melatonin are unknown. e
physician most likely prescribes medications that have serious side e ects because the medications’
bene ts outweigh the risks posed by their side e ects. In the case of synthetic melatonin, however,
this kind of decision cannot be made.
A e patient’s argument has to do with whether the physician’s refusal to prescribe synthetic melatonin is
consistent with the physician’s usual prescription practices. e question of whether naturally produced
melatonin has di erent side e ects than synthetic melatonin has no bearing on that argument.
B It is quite reasonable for the patient’s argument not to mention this possibility, especially since the
physician expresses a belief that synthetic melatonin may be e ective—but expresses no belief about
whether or not it has been conclusively shown to be e ective.
C Awareness that sleep disorders can lead to serious medical complications most likely prompts the patient’s
desire for treatment—but the patient’s not mentioning this possible consequence of sleep disorders does
not indicate a aw in the argument.
D e patient makes clear that the physician prescribes medications that have serious side e ects; the time
those side e ects take to manifest themselves is not relevant to the argument.
E Correct. e patient’s argument is awed in failing to consider this key di erence between known risks
and unknown risks. If the patient had considered this key di erence, the patient would have realized that
the physician’s position is not at all inconsistent, and that the physician’s refusal to prescribe is genuinely
based on a concern about an unknown risk.
e correct answer is E.
571
8.6 Critical Reasoning Answer Explanations
568. Hollywood restaurant is replacing some of its standard tables with tall tables and stools. The restaurant already lls every
available seat during its operating hours, and the change in seating arrangements will not result in an increase in the
restaurant’s seating capacity. Nonetheless, the restaurant’s management expects revenue to increase as a result of the
seating change without any concurrent change in menu, prices, or operating hours.
Which of the following, if true, provides the best reason for the expectation?
(A) One of the taller tables takes up less oor space than one of the standard tables.
(B) Diners seated on stools typically do not linger over dinner as long as diners seated at standard tables.
(C) Since the restaurant will replace only some of its standard tables, it can continue to accommodate customers who do
not care for the taller tables.
(D) Few diners are likely to avoid the restaurant because of the new seating arrangement.
(E) The standard tables being replaced by tall tables would otherwise have to be replaced with new standard tables at a
greater expense.
Argument Construction
Situation Hollywood restaurant is replacing some of its tables with taller tables and stools, and the
management expects this will increase revenue, despite the fact that the restaurant already lls all
of its available seats and that this change will not increase seating capacity. Furthermore, there will
not be any change in menu, prices, or operating hours.
Reasoning What would strongly support the management’s expectation? Since the new seating will not increase
the restaurant’s seating capacity, the management’s expectations must be based on a belief that the
change to taller tables and stools will somehow change diners’ behavior, perhaps by leading them
to order more food, or to stay at their tables for a shorter time, thereby allowing the restaurant to
serve more diners during its operating hours without increasing seating capacity. If diners seated
at tall tables and on tall stools spend less time lingering over their dinners, then they will leave
sooner, opening up the tables for more diners. Because the restaurant, before the change, already
lls every available seat during its operating hours, it is reasonable to think that it will be able to
serve more diners than it currently does, thereby selling more food and thus increasing revenue.
A is would be relevant if we could infer from it that seating capacity will increase. However, the passage
indicates that the new seating arrangement will not result in greater capacity.
B Correct. Because the restaurant will be able to serve more meals during its operating hours, the
restaurant’s revenue can be expected to increase.
C is may indicate that the restaurant is less likely to alienate customers who do not care for tall tables
and stools, but that only supports the claim that the restaurant will not lose customers and therefore lose
revenue; it does not indicate that the restaurant will see revenue increase.
D Again, this merely indicates that there will not be a loss—or much loss—of revenue, not that there will be
an increase in revenue.
E Less expensive tables will decrease the restaurant’s costs, but it will not increase the restaurant’s revenue.
e correct answer is B.
572
GMAT® Offi cial Guide 2018
569. A major network news organization experienced a drop in viewership in the week following the airing of a controversial
report on the economy. The network also received a very large number of complaints regarding the report. The network,
however, maintains that negative reactions to the report had nothing to do with its loss of viewers.
Which of the following, if true, most strongly supports the network’s position?
(A) The other major network news organizations reported similar reductions in viewership during the sameweek.
(B) The viewers who registered complaints with the network were regular viewers of the news organization’s programs.
(C) Major network news organizations publicly attribute drops in viewership to their own reports only when they receive
complaints about those reports.
(D) This was not the rst time that this network news organization has aired a controversial report on the economy that
has inspired viewers to complain to the network.
(E) Most network news viewers rely on network news broadcasts as their primary source of information regarding the
economy.
Argument Construction
Situation A major network news organization aired a controversial report on the economy, and the following
week the network’s viewership declined. e network claims that the loss of viewers was not
connected with negative reactions to the report.
Reasoning Which statement most strongly supports the network’s position? If other major news network
organizations had similar drops in viewership, it is implausible to think that the controversial
report accounted for the other organizations’ drops in viewership. On the other hand, it is not
implausible to suppose that whatever did cause the drop in the viewership experienced by other
network news organizations—e.g., holidays, weather, popular non‐news programming—also had
that e ect on the organization that ran the controversial report. is would give some reason to
believe that it was not the report that accounts for the organization’s drop in viewership.
A Correct. is statement indicates that something other than the airing of the report could account for the
subsequent drop in the organization’s viewership.
B If anything, this statement tends to undermine the network’s claim, because it suggests that the report
o ended people who otherwise might have continued to watch the organization’s programming.
C Since the network did in fact receive complaints about the report, this statement is irrelevant.
D e fact that the network has received complaints before about controversial reports on the economy
that the network’s news organization has aired tells us nothing about whether this recent report caused a
subsequent drop in viewership.
E e fact that viewers turn to network news broadcasts as their primary source of information about
the economy tells us nothing about whether viewers might stop watching a particular network news
organization’s programs as a result of its airing a controversial report on the economy.
e correct answer is A.
573
8.6 Critical Reasoning Answer Explanations
570. Only a reduction of 10 percent in the number of scheduled ights using Greentown’s airport will allow the delays that are so
common there to be avoided. Hevelia airstrip, 40 miles away, would, if upgraded and expanded, be an attractive alternative
for fully 20 percent of the passengers using Greentown airport. Nevertheless, experts reject the claim that turning Hevelia
into a full‐service airport would end the chronic delays at Greentown.
Which of the following, if true, most helps to justify the experts’ position?
(A) Turning Hevelia into a full‐service airport would require not only substantial construction at the airport itself, but also
the construction of new access highways.
(B) A second largely undeveloped airstrip close to Greentown airport would be a more attractive alternative than Hevelia
for many passengers who now use Greentown.
(C) Hevelia airstrip lies in a relatively undeveloped area but would, if it became a full‐service airport, be a magnet for
commercial and residential development.
(D) If an airplane has to wait to land, the extra jet fuel required adds signi cantly to the airline’s costs.
(E) Several airlines use Greentown as a regional hub, so that most ights landing at Greentown have many passengers
who then take different ights to reach their nal destinations.
Evaluation of a Plan
Situation To avoid the delays now common at Greentown’s airport, the number of scheduled ights
there would need to be reduced by 10 percent. If the nearby Hevelia airstrip were expanded and
upgraded, it would be an attractive alternative for 20 percent of Greentown airport’s passengers.
Still, experts do not believe that the delays at Greentown would end even if Hevelia were turned
into a full‐service airport.
Reasoning Which statement most supports the experts’ position? If the number of ights at Greentown’s airport
did not drop by at least 10 percent, despite the fact that 20 percent of the passengers who currently
use Greentown’s airport would nd nearby Hevelia airstrip an attractive alternative, then the
delays would not be avoided. Airlines generally use certain airports as regional hubs—an airport
through which an airline routes most of its tra c—so, even if many passengers would be willing
to use Hevelia airstrip, the number of ights at Greentown may not decline signi cantly, or at all.
A e experts’ position concerns what would happen to the ight delays at Greentown airport if the Hevelia
airstrip were converted into a full‐service airport. So the fact that there are great costs involved in making
such a conversion—possibly making such a conversion unlikely—has no bearing on the e ects such a
conversion would have on ight delays at Greentown if the conversion were to be carried out.
B is statement indicates that the undeveloped airstrip near Greentown might be a better way to alleviate
ight delays at Greentown, but it tells us nothing about the e ects that converting the Hevelia airstrip to a
full‐service airport would have were it to be carried out.
C is in no way explains why converting the Hevelia airstrip into a full‐service airport would not alleviate
the problem with ight delays at Greentown.
D is provides a reason to think that reducing the number of ights at Greentown might make the airport
more e cient. But that has no bearing on the e ect that converting the Hevelia airstrip to a full‐service
airport might have on ight delays at Greentown.
E Correct. is statement provides support for the experts’ position because it gives a reason for thinking
that the number of scheduled ights at Greentown would not be reduced, even if Hevelia airstrip became
an attractive alternative for some 20 percent of Greentown’s passengers.
e correct answer is E.
574
GMAT® Offi cial Guide 2018
571. For similar cars and comparable drivers, automobile insurance for collision damage has always cost more in Greatport than
in Fairmont. Police studies, however, show that cars owned by Greatport residents are, on average, slightly less likely to be
involved in a collision than cars in Fairmont. Clearly, therefore, insurance companies are making a greater pro t on collision‐
damage insurance in Greatport than in Fairmont.
In evaluating the argument, it would be most useful to compare
(A) the level of traf c congestion in Greatport with the level of traf c congestion in Fairmont
(B) the cost of repairing collision damage in Greatport with the cost of repairing collision damage in Fairmont
(C) the rates Greatport residents pay for other forms of insurance with the rates paid for similar insurance by residents of
Fairmont
(D) the condition of Greatport’s roads and streets with the condition of Fairmont’s roads and streets
(E) the cost of collision‐damage insurance in Greatport and Fairmont with that in other cities
Argument Evaluation
Situation A particular kind of insurance, that for collision damage, costs more in Greatport than in
Fairmont. e cars of Greatport residents are, however, less likely to be involved in collisions
than are cars of Fairmont residents. So insurance companies must be making a greater pro t on
collision‐damage insurance in Greatport than in Fairmont.
Reasoning What would it help to consider in evaluating the argument? Insurance companies would make greater
pro ts on collision‐damage insurance in Greatport than they make in Fairmont if they pay out
less money in response to Greatport residents’ claims than they do in response to Fairmont’s
residents’ claims. at Greatport residents’ cars are involved in fewer collisions than are Fairmont’s
residents’ cars supports this—if there are fewer collisions overall, then the insurance companies
might pay out less money overall. But the number of collisions is only one factor contributing
to how much money an insurance company pays out in response to claims; another factor is the
amount of damage in icted on the cars involved in collisions and how much it costs to repair that
damage. ese costs would need to be considered before concluding that insurance companies’
pro ts on collision‐damage insurance are greater in Greatport than in Fairmont.
A e level of tra c congestion probably contributes to the frequency of collisions in each town. e
information given, however, includes the statement that Greatport cars are less likely to be involved
in collisions than are Fairmont cars. Why this occurs—whether, for example, tra c congestion is a
contributory factor—is not relevant.
B Correct. is is clearly a factor that would a ect the pro tability of insurance in the two towns—and is
therefore highly relevant to evaluating the argument, especially its conclusion.
C e argument’s conclusion is about insurance companies’ pro ts on collision‐damage insurance alone, so
other types of insurance, and the rates paid for them, are not relevant.
D e condition of the roads and streets in each town probably contributes to the frequency of collisions in
each town. e information given, however, includes the statement that Greatport cars are less likely to be
involved in collisions than are Fairmont cars. Why this is so—whether, for example, the condition of the
roads is a contributory cause—is not relevant.
E Since the argument is concerned solely with collision‐insurance costs and pro ts in Greatport and
Fairmont, comparing the cost of insurance in those towns with the cost of insurance elsewhere would
provide no useful insight.
e correct answer is B.
575
8.6 Critical Reasoning Answer Explanations
572. The air quality board recently informed Coffee Roast, a small coffee roasting rm, of a complaint regarding the smoke
from its roaster. Recently enacted air quality regulations require machines roasting more than 10 pounds of coffee to be
equipped with expensive smoke‐dissipating afterburners. The rm, however, roasts only 8 pounds of coffee at a time.
Nevertheless, the company has decided to purchase and install an afterburner.
Which of the following, if true, most strongly supports the rm’s decision?
(A) Until settling on the new air quality regulations, the board had debated whether to require afterburners for machines
roasting more than 5 pounds of coffee at a time.
(B) Coffee roasted in a machine equipped with an afterburner has its avor subtly altered.
(C) The cost to the rm of an afterburner is less than the cost of replacing its roaster with a smaller one.
(D) Fewer complaints are reported in areas that maintain strict rules regarding afterburners.
(E) The rm has reason to fear that negative publicity regarding the complaints could result in lost sales.
Evaluation of a Plan
Situation After being informed of a complaint about smoke from its co ee roaster, a rm decided to
purchase and install an afterburner to reduce or eliminate emissions of smoke, even though the
roaster roasts too little co ee at a time for an afterburner to be legally required.
Reasoning What would have been a good reason for the rm to buy and install the afterburner? e only factors
mentioned that might give the rm reason to buy an afterburner are the complaint about smoke
and the regulations requiring an afterburner. Since the regulations do not apply in this case, the
complaint is more likely to have motivated the rm’s decision. Any serious potential consequences
the rm might have faced from failure to address the complaint could have provided a good reason
to buy and install the afterburner.
A If this debate had still been ongoing when the rm made its decision, uncertainty about the pending
regulations might have justi ed the decision. But the debate had already been settled before the rm
decided to purchase the afterburner, and the regulations clearly did not require one.
B An unspeci ed alteration in avor is not clearly a good reason to use an afterburner—the afterburner
might worsen the avor.
C e rm’s roaster was already small enough that the regulations did not require it to be replaced, even
without an afterburner.
D is reason relates only to rules regarding afterburners, not to Co ee Roast’s purchase of an afterburner,
which was not mandated by regulations. Furthermore, it could be that the air quality regulations recently
enacted are among the strictest in any region, which could result in fewer complaints regardless of whether
Co ee Roast installs an afterburner.
E Correct. Since installing an afterburner is a plausible way to address the complaint and prevent future
complaints, the rm has plausible reasons to believe this strategy will help it avoid the negative publicity
and lost sales it fears. ese considerations could have reasonably justi ed its decision.
e correct answer is E.
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GMAT® Offi cial Guide 2018
573. The tulu, a popular ornamental plant, does not reproduce naturally, and is only bred and sold by specialized horticultural
companies. Unfortunately, the tulu is easily devastated by a contagious fungal rot. The government ministry plans to
reassure worried gardeners by requiring all tulu plants to be tested for fungal rot before being sold. However, infected
plants less than 30 weeks old have generally not built up enough fungal rot in their systems to be detected reliably. And
many tulu plants are sold before they are 24 weeks old.
Which of the following, if performed by the government ministry, could logically be expected to overcome the problem with
their plan to test for the fungal rot?
(A) Releasing a general announcement that tulu plants less than 30 weeks old cannot be effectively tested for fungal rot
(B) Requiring all tulu plants less than 30 weeks old to be labeled as such
(C) Researching possible ways to test tulu plants less than 24 weeks old for fungal rot
(D) Ensuring that tulu plants not be sold before they are 30 weeks old
(E) Quarantining all tulu plants from horticultural companies at which any case of fungal rot has been detected until those
tulu plants can be tested for fungal rot
Evaluation of a Plan
Situation ere is a contagious fungal rot that devastates the tulu, a popular ornamental plant. To reassure
worried gardeners, the government ministry plans to require that tulu plants be tested for the rot
before being sold. However, many tulu plants are sold before they are 24 weeks old, yet fungal rot
in plants less than 30 weeks old generally cannot be detected reliably.
Reasoning What could the government ministry do to overcome the problem? e problem arises from the fact
that tulu plants are frequently sold before they are 24 weeks old, which is too soon for any fungal
rot that is present to have built up enough in their root systems to be detected. Since the goal
of the testing is to ensure that infected tulu plants not be sold, an obvious solution would be to
make sure that no plants are sold before they are old enough for fungal rot to have built up to a
detectable level. us, tulu plants should not be sold before they are 30 weeks old.
A Releasing such an announcement would help overcome the problem if it guaranteed that no one
would buy or sell tulu plants before the plants were 30 weeks old, but it is far from certain that such an
announcement would guarantee this.
B Since some people may not be aware of the signi cance of such labeling, such labeling might have very
little e ect.
C ere is no guarantee that such research will be successful at reducing the age at which tulu plants can be
reliably tested.
D Correct. If the government ensures that no tulu plants less than 30 weeks of age are sold, then the speci c
problem mentioned in the passage would be overcome.
E is will not help overcome the problem. Such a quarantine program might lead horticultural companies
to start selling tulu plants only if they are less than 24 weeks old, thereby minimizing the chance of
quarantine by minimizing the chance of detection.
e correct answer is D.
577
8.6 Critical Reasoning Answer Explanations
574. People who do regular volunteer work tend to live longer, on average, than people who do not. It has been found that “doing
good,” a category that certainly includes volunteer work, releases endorphins, the brain’s natural opiates, which induce
in people a feeling of well‐being. Clearly, there is a connection: Regular releases of endorphins must in some way help to
extend people’s lives.
Which of the following, if true, most seriously undermines the force of the evidence given as support for the hypothesis that
endorphins promote longevity?
(A) People who do regular volunteer work are only somewhat more likely than others to characterize the work they do for
a living as “doing good.”
(B) Although extremely high levels of endorphins could be harmful to health, such levels are never reached as a result of
the natural release of endorphins.
(C) There are many people who have done some volunteer work but who do not do such work regularly.
(D) People tend not to become involved in regular volunteer work unless they are healthy and energetic to begin with.
(E) Releases of endorphins are responsible for the sense of well‐being experienced by many long‐distance runners while
running.
Argument Evaluation
Situation People who volunteer regularly live longer on average than people who do not. Doing good work,
including volunteer work, releases endorphins, which induce a feeling of well‐being.
Reasoning What additional ndings would suggest that the cited evidence does not indicate that endorphins increase
longevity? e argument implicitly assumes that the reason regular volunteers tend to live longer
is that volunteering lengthens their lives. It further assumes that no factor that is correlated with
volunteering, other than the endorphin release, would plausibly explain how volunteering could
have this e ect. Findings that cast doubt on either of these assumptions would undermine the
connection between the cited evidence and the conclusion that endorphins promote longevity.
A Volunteering might greatly boost volunteers’ endorphin levels even if the work the volunteers do for a
living is no di erent from other people’s work.
B Even if unnaturally high endorphin levels could harm health, the levels attainable through volunteer work
may promote health.
C e argument is about an observed correlation in a certain group of people (those who regularly do
volunteer work). How many people are outside that group (i.e., do not regularly do volunteer work) is
independent of the question of what causes the observed correlation. Even if some people volunteer only
occasionally, volunteering regularly may promote longevity by causing regular releases of endorphins.
D Correct. is suggests that the initially better health of people who choose to volunteer could fully explain
the cited correlation between volunteering and longevity.
E Unless we are also given evidence that long‐distance runners tend not to live longer than other people,
this does not undermine the purported evidence in the argument. Endorphins might promote longevity in
both regular volunteers and long‐distance runners.
e correct answer is D.
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GMAT® Offi cial Guide 2018
575. In Mernia commercial fossil hunters often sell important fossils they have found, not to universities or museums, but to
individual collectors, who pay much better but generally do not allow researchers access to their collections. To increase
the number of fossils available for research, some legislators propose requiring all fossils that are found in Mernia to be
sold only to universities or museums.
Which of the following, if true, most strongly indicates that the legislators’ proposal will fail to achieve its goal?
(A) Some fossil hunters in Mernia are not commercial fossil hunters, but rather are amateurs who keep the fossils that
they nd.
(B) Most fossils found in Mernia are common types that have little scienti c interest.
(C) Commercial fossil hunters in Mernia currently sell some of the fossils they nd to universities and museums.
(D) Many universities in Mernia do not engage in fossil research.
(E) Most fossils are found by commercial fossil hunters, and they would give up looking for fossils if they were no longer
allowed to sell to individual collectors.
Evaluation of a Plan
Situation Fossil hunters in Mernia often sell important fossils to collectors who do not make them
accessible to researchers. To increase the number of fossils available for research, some legislators
propose requiring all fossils found in Mernia to be sold only to universities or museums.
Reasoning What would most strongly suggest that requiring all fossils found in Mernia to be sold only to universities
or museums would not increase the number of fossils available for research? To increase the number of
fossils available for research, the proposed requirement will have to be implemented and e ectively
enforced. It will presumably have to increase the total number of fossils sold to universities and
museums. And those institutions will have to make more of the fossils in their collections available
to researchers than the private collectors do. Evidence that any of those conditions will not be
ful lled would suggest that the legislators’ proposal will fail to achieve its goal.
A Even if the legislation does not a ect fossils kept by amateurs, it might still result in many more fossils
being sold to universities or museums rather than to private collectors, and thus might still increase the
number of fossils available for research.
B Even if few Mernian fossils are interesting to researchers, the legislation could still achieve its goal of
making more fossils available for research.
C Even if commercial fossil hunters already sell a few fossils to universities and museums, the legislation
could encourage them to sell many more fossils.
D e universities that do not engage in fossil research presumably will not be interested in buying fossils
even if the legislation passes. But the fossil hunters can just sell their fossils to other universities and
museums that do engage in fossil research.
E Correct. is suggests that if the legislation passes, fossils will simply be left in the ground rather than
sold to private collectors. at would not increase the total number of fossils available for research.
e correct answer is E.
579
8.6 Critical Reasoning Answer Explanations
576. The Eurasian ruffe, a sh species inadvertently introduced into North America’s Great Lakes in recent years, feeds on the
eggs of lake white sh, a native species, thus threatening the lakes’ natural ecosystem. To help track the ruffe’s spread,
government agencies have produced wallet‐sized cards about the ruffe. The cards contain pictures of the ruffe and explain
the danger they pose; the cards also request anglers to report any ruffe they catch.
Which of the following, if true, would provide most support for the prediction that the agencies’ action will have its intended
effect?
(A) The ruffe has spiny ns that make it unattractive as prey.
(B) Ruffe generally feed at night, but most recreational shing on the Great Lakes is done during daytime hours.
(C) Most people who sh recreationally on the Great Lakes are interested in the preservation of the lake white sh because
it is a highly prized game sh.
(D) The ruffe is one of several nonnative species in the Great Lakes whose existence threatens the survival of lake
white sh populations there.
(E) The bait that most people use when shing for white sh on the Great Lakes is not attractive to ruffe.
Evaluation of a Plan
Situation e Eurasian ru e, a species not native to the Great Lakes, is threatening the native lake white sh.
Government agencies hope that wallet‐sized cards identifying the ru e, explaining the danger
they pose, and asking anglers to report their ru e catches will help them track the ru e’s spread.
Reasoning What point would support the idea that the agencies’ action will have its intended e ect? e cards are
intended to help government agencies track the ru e’s spread. ey will be useful for this purpose
only if anglers actually report the ru e they catch. us anything that increases the odds of anglers’
doing such reporting would make it more likely that the cards will have their intended e ect.
A If ru e are unattractive as prey, they will probably spread more quickly in the Great Lakes. is will most
likely have little e ect on whether the wallet‐sized cards will help government agencies track the ru e.
B If ru e feed at night, while shing is done in the daytime, it is unlikely that anglers would catch ru e. us
few catches would be reported to government agencies, making it more di cult for those agencies to track
the spread of ru e.
C Correct. is statement properly identi es a point that supports the prediction that the agencies’ action
will have its intended e ect—that is, those who are interested in preserving the lake white sh will be likely
to report catches of ru e, which threaten white sh, thus enabling the agencies’ tracking of the spread of
ru e.
D at the ru e is one of several nonnative species threatening the Great Lakes lessens the odds that the
white sh will survive, but this has no e ect on the question of whether the wallet‐sized cards will help
government agencies track the ru e’s spread.
E is would make it likely that anglers would catch few ru e. If anglers do not catch many ru e, there
will not be many to report to government agencies, which would in turn make it more di cult for those
agencies to track the ru e’s spread.
e correct answer is C.
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GMAT® Offi cial Guide 2018
577. Which of the following most logically completes the argument below?
Although the number of large arti cial satellites orbiting the Earth is small compared to the number of small pieces of debris in
orbit, the large satellites interfere more seriously with telescope observations because of the strong re ections they produce.
Because many of those large satellites have ceased to function, the proposal has recently been made to eliminate interference
from nonfunctioning satellites by exploding them in space. This proposal, however, is ill conceived, since ________.
(A) many nonfunctioning satellites remain in orbit for years
(B) for satellites that have ceased to function, repairing them while they are in orbit would be prohibitively expensive
(C) there are no known previous instances of satellites’ having been exploded on purpose
(D) the only way to make telescope observations without any interference from debris in orbit is to use telescopes
launched into extremely high orbits around the Earth
(E) a greatly increased number of small particles in Earth’s orbit would result in a blanket of re ections that would make
certain valuable telescope observations impossible
Evaluation of a Plan
Situation Many large arti cial satellites orbiting Earth no longer function. Re ections from these satellites
interfere with telescope observations. A proposal has been made to eliminate this interference by
exploding these satellites in space.
Reasoning Why is the proposal ill conceived? If exploding the large arti cial satellites—thereby creating a large
amount of debris—would result in an increase in interference with telescope observation, the
proposal would be self‐defeating, and therefore would be ill conceived.
A e fact that many nonfunctioning satellites remain in orbit for years would seem to make the proposal
more attractive. If large nonfunctioning arti cial satellites generally do not remain in orbit for years—e.g.,
if they fall out of orbit—then there might be no need to explode the satellites. erefore this statement is
not correct.
B is statement, too, makes the proposal more attractive—the opposite of what is called for. If
nonfunctioning satellites cannot be repaired, then that eliminates one possible reason for not blowing
them up.
C e fact that there are no known instances of intentional explosions of satellites does not show that the
plan is ill conceived. At most this might suggest that the consequences of such an explosion are not well
understood, but even that is not very strongly suggested. For instance, if large arti cial satellites have
accidentally blown up, scientists may have studied the results and have good reason to believe that no
ill e ects will result from exploding the satellites.
D is is not a cogent reason for thinking the proposal to be ill conceived. Even if the proposal would not
eliminate all interference with ground based telescopes, it might still greatly reduce interference.
E Correct. If exploding large nonfunctioning satellites would lead to more interference, then we have a
reason to think that the proposal is ill conceived.
e correct answer is E.
581
8.6 Critical Reasoning Answer Explanations
578. Thyrian lawmaker: Thyria’s Cheese Importation Board inspects all cheese shipments to Thyria and rejects shipments not
meeting speci ed standards. Yet only 1 percent is ever rejected. Therefore, since the health consequences and associated
economic costs of not rejecting that 1 percent are negligible, whereas the board’s operating costs are considerable, for
economic reasons alone the board should be disbanded.
Consultant: I disagree. The threat of having their shipments rejected deters many cheese exporters from shipping
substandard product.
The consultant responds to the lawmaker’s argument by
(A) rejecting the lawmaker’s argument while proposing that the standards according to which the board inspects imported
cheese should be raised
(B) providing evidence that the lawmaker’s argument has signi cantly overestimated the cost of maintaining the board
(C) objecting to the lawmaker’s introducing into the discussion factors that are not strictly economic
(D) pointing out a bene t of maintaining the board, which the lawmaker’s argument has failed to consider
(E) shifting the discussion from the argument at hand to an attack on the integrity of the cheese inspectors
Argument Construction
Situation e yrian lawmaker argues that the Cheese Importation Board should be disbanded, because
its operating costs are high and it rejects only a small percentage of the cheese it inspects. e
consultant disagrees, pointing out that the board’s inspections deter those who export cheese to
yria from shipping substandard cheese.
Reasoning What strategy does the consultant use in the counterargument? e consultant indicates to the
lawmaker that there is a reason to retain the board that the lawmaker has not considered. e
bene t the board provides is not that it identi es a great deal of substandard cheese and rejects
it (thus keeping the public healthy), but that the possibility that their cheese could be found
substandard is what keeps exporters from attempting to export low‐quality cheese to yria.
A e consultant does reject the lawmaker’s argument, but the consultant does not propose higher standards.
Indeed, in suggesting that the board should be retained, the consultant implies that the board’s standards
are appropriate.
B e consultant does not provide any evidence related to the board’s cost.
C e only point the lawmaker raises that is not strictly economic is about the health consequences of
disbanding the board, but the consultant does not address this point at all.
D Correct. is statement properly identi es the strategy the consultant employs in his or her
counterargument. e consultant points out that the board provides a signi cant bene t that the lawmaker
did not consider.
E e consultant does not attack the integrity of the cheese inspectors; to the contrary, the consultant says
that their inspections deter the cheese exporters from shipping substandard cheese.
e correct answer is D.
582
GMAT® Offi cial Guide 2018
579. The growing popularity of computer‐based activities was widely expected to result in a decline in television viewing, since
it had been assumed that people lack suf cient free time to maintain current television‐viewing levels while spending
increasing amounts of free time on the computer. That assumption, however, is evidently false: In a recent mail survey
concerning media use, a very large majority of respondents who report increasing time spent per week using computers
report no change in time spent watching television.
Which of the following would it be most useful to determine in order to evaluate the argument?
(A) Whether a large majority of the survey respondents reported watching television regularly
(B) Whether the amount of time spent watching television is declining among people who report that they rarely or never
use computers
(C) Whether the type of television programs a person watches tends to change as the amount of time spent per week
using computers increases
(D) Whether a large majority of the computer owners in the survey reported spending increasing amounts of time per
week using computers
(E) Whether the survey respondents’ reports of time spent using computers included time spent using computers at work
Argument Evaluation
Situation e argument is intended to debunk the assumption that people lack su cient free time to
maintain television‐viewing levels while spending increasing amounts of free time on the
computer. To do so, it cites a survey of media use in which a large majority of respondents who
spend increasing amounts of time using computers also claim to have not altered the amount of
time they spend watching television.
Reasoning What would it be most useful to know in order to evaluate the argument? e argument uses the survey
results to claim that people have enough free time to both maintain their television viewing levels
and spend increasing amounts of free time on the computer. But the survey, as reported here, did
not address whether people are spending their free time on the computer; the respondents reported
increasing time spent per week using computers. Since the argument is about free time, it is
important to know whether this is actually what the respondents were reporting.
A e argument is concerned with the change in the amount of television watched by those whose computer
use increased, so whether the survey’s respondents reported watching television regularly is irrelevant.
B e argument is concerned with the change in the amount of television watched by those whose computer
use has increased, so it does not matter whether the amount of time spent watching television among
people who do not use computers is declining, remaining the same, or increasing.
C e argument is concerned with the amount of television watched by those whose computer use has
increased, not the type of television programs such a person does or does not watch.
D e argument here is concerned with people who report spending increasing amounts of time on the
computer; what computer owners do is a separate question.
E Correct. is statement properly identi es something that would be useful to know in evaluating the
argument: whether the survey data included time spent using computers at work—if it did, this would
make the data misleading as evidence for the argument’s conclusion.
e correct answer is E.
583
8.6 Critical Reasoning Answer Explanations
580. Although the school would receive nancial bene ts if it had soft drink vending machines in the cafeteria, we should not
allow them. Allowing soft drink machines there would not be in our students’ interest. If our students start drinking more soft
drinks, they will be less healthy.
The argument depends on which of the following?
(A) If the soft drink vending machines were placed in the cafeteria, students would consume more soft drinks as a result.
(B) The amount of soft drinks that most students at the school currently drink is not detrimental to their health.
(C) Students are apt to be healthier if they do not drink soft drinks at all than if they just drink small amounts occasionally.
(D) Students will not simply bring soft drinks from home if the soft drink vending machines are not placed in the cafeteria.
(E) The school’s primary concern should be to promote good health among its students.
Argument Construction
Situation Allowing soft drink vending machines in a school cafeteria would nancially bene t the school,
but students who drink more soft drinks would become less healthy.
Reasoning What must be true in order for the claim that students drinking more soft drinks would cause them to
become less healthy to justify the conclusion that soft drink vending machines should not be allowed in
the cafeteria? e argument is that because drinking more soft drinks would be unhealthy for the
students, allowing the vending machines would not be in the students’ interest, so the vending
machines should not be allowed. is reasoning depends on the implicit factual assumption that
allowing the vending machines would result in the students drinking more soft drinks. It also
depends on the implicit value judgment that receiving nancial bene ts should be less important
to the school than preventing a situation that would make the students less healthy.
A Correct. If the cafeteria vending machines would not result in students consuming more soft drinks, then
allowing the machines would not harm the students’ health in the way the argument assumes.
B Even if the amount of soft drinks the students currently drink were unhealthy, enabling the students to
drink more could make them even less healthy.
C Even if drinking small amounts of soft drinks occasionally would not harm the students, vending
machines in the cafeteria could lead the students to drink excessive amounts.
D Even if students who cannot buy soft drinks in the cafeteria sometimes bring them from home instead,
adding vending machines in the cafeteria could increase the students’ overall soft drink consumption.
E A concern does not have to be the primary one in order to be valid and important. It could be held that
promoting students’ good health should not be the schools’ primary concern but should still be a more
important concern than the nancial bene ts from the vending machines.
e correct answer is A.
584
GMAT® Offi cial Guide 2018
581. Many athletes inhale pure oxygen after exercise in an attempt to increase muscular reabsorption of oxygen. Measured
continuously after exercise, however, the blood lactate levels of athletes who inhale pure oxygen are practically identical,
on average, to those of athletes who breathe normal air. The lower the blood lactate level is, the higher the muscular
reabsorption of oxygen is.
If the statements above are all true, they most strongly support which of the following conclusions?
(A) Athletes’ muscular reabsorption of oxygen is not increased when they inhale pure oxygen instead of normal air.
(B) High blood lactate levels cannot be reduced.
(C) Blood lactate levels are a poor measure of oxygen reabsorption by muscles.
(D) The amount of oxygen reabsorbed by an athlete’s muscles always remains constant.
(E) The inhaling of pure oxygen has no legitimate role in athletics.
Argument Construction
Situation Blood lactate levels after exercise are practically identical in athletes who breathe normal air and
in those who inhale pure oxygen after exercise. e lower the blood lactate level, the higher the
muscular reabsorption of oxygen.
Reasoning What conclusion do the stated facts most strongly support? We are told that lower blood lactate levels
correspond consistently to higher muscular reabsorption of oxygen. Since athletes who breathe
pure oxygen after exercise have blood lactate levels practically identical to those in athletes who
breathe normal air, probably muscular reabsorption of oxygen does not di er signi cantly between
athletes who breathe pure oxygen and those who breathe pure air.
A Correct. As explained above, the stated facts suggest that muscular reabsorption of oxygen does not di er
signi cantly between athletes who breathe pure oxygen and those who breathe pure air. So breathing pure
oxygen instead of normal air after exercise probably does not increase athletes’ muscular reabsorption of
oxygen.
B None of the statements indicates that blood lactate levels cannot be reduced by means other than inhaling
pure oxygen.
C We are told that blood lactate levels are negatively correlated with muscular reabsorption of oxygen. is
negative correlation might allow muscular reabsorption of oxygen to be precisely determined by measuring
blood lactate levels.
D Muscular reabsorption of oxygen might vary for reasons unrelated to whether an athlete has been inhaling
pure oxygen.
E Inhaling pure oxygen might have some legitimate role unrelated to muscular reabsorption of oxygen.
e correct answer is A.
585
8.6 Critical Reasoning Answer Explanations
582. Which of the following most logically completes the argument?
Sviatovin is a medieval Moringian text whose author and exact date of composition are unknown. However, the events in the
life of Prince Sviatov that the text describes occurred in 1165, and in the diagram of Sviatov’s family that accompanies the
text his father, who died in 1167, is identi ed as still living. Thus Sviatovin must have been written between 1165 and 1167,
assuming that ________.
(A) the life of Prince Sviatov is not the subject of any other medieval Moringian texts
(B) the author of Sviatovin intended it to provide as accurate a report about Prince Sviatov’s exploits as possible
(C) the diagram accurately represents the composition of Sviatov’s family at the time Sviatovin was written
(D) Sviatovin is the earliest Moringian text whose composition can be dated to within a few years
(E) Sviatovin was not written by Sviatov’s father himself
Argument Construction
Situation A medieval Moringian text was written about Prince Sviatov. It is not known exactly when the
text was written, but the events described in it occurred in 1165 and a diagram in the text indicates
that Sviatov’s father—who died in 1167—was alive at the time it was composed.
Reasoning What completion of the blank would provide the best reason for believing the argument’s conclusion?
e argument’s conclusion is that the book Sviatovin was written between 1165 and 1167. e
reasoning given is this: It could not have been written before 1165 because it includes events that
took place in that year. It could not have been written after 1167 because Sviatov’s father died
in that year. A diagram in the book suggests he was alive when the book was written. Was the
diagram correct in that suggestion? e argument depends on assuming that it was.
A e argument focuses on one text and its date of composition. e argument does not need to make any
assumptions about other texts.
B e argument does not assume this. Issues about the accurate reporting of Sviatov’s exploits (or about the
author’s intention to report them accurately) are irrelevant to the argument, which hinges on the accuracy
of the diagram that accompanies the text. e diagram does not report Sviatov’s exploits.
C Correct. e reasoning in the argument assumes that the diagram was correct in representing the Prince’s
father as still living when the text was composed. If his father was not living when the text was written,
then the information that his father actually died in 1167 is no guarantee that the text was composed by
then.
D See the explanation for answer choice (A) above. e degree of precision with which scholars have
succeeded in dating other Moringian texts is entirely irrelevant.
E e conclusion concerns when Sviatovin was written and not by whom it was written. If, contrary to
answer choice (E), it were known that the author was Sviatov’s father, this would actually provide strong
support for the argument’s conclusion. us answer choice (E) does not provide a good reason for the
argument’s conclusion.
e correct answer is C.
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GMAT® Offi cial Guide 2018
583. A study of ticket sales at a summer theater festival found that people who bought tickets to individual plays had a no‐show
rate of less than 1 percent, while those who paid in advance for all ten plays being performed that summer had a no‐show
rate of nearly 30 percent. This may be at least in part because the greater the awareness customers retain about the cost
of an item, the more likely they are to use it.
Which of the following would, if true, best serve as an alternative explanation of the results of the study?
(A) The price per ticket was slightly cheaper for those who bought all ten tickets in advance.
(B) Many people who attended the theater festival believed strongly that they should support it nancially.
(C) Those who attended all ten plays became eligible for a partial refund.
(D) Usually, people who bought tickets to individual plays did so immediately prior to each performance that they
attended.
(E) People who arrived just before the performance began could not be assured of obtaining seats in a preferred
location.
Argument Construction
Situation People who bought tickets to individual plays at a theater festival had a much lower no‐show rate
than did people who paid in advance for all ten plays.
Reasoning What factor other than greater awareness of the ticket costs could explain why people who bought tickets
individually were more likely to attend the plays? e passage suggests that people who bought
tickets individually were more likely to attend the plays because they were more vividly aware of
what they had paid for each ticket. But there are other possible explanations—perhaps the people
who bought the tickets individually were more eager to attend each play for its own sake, or had
other characteristics or incentives that made them more likely to attend the plays.
A A slight price di erence would not plausibly explain why the no‐show rate was thirty times greater among
those who bought all the tickets in advance than among those who bought them individually.
B is could be true of many people who bought their tickets individually as well as many who bought them
in advance.
C is would provide an added incentive for those who bought tickets in advance to attend all the plays.
D Correct. If people who bought individual tickets usually did so right before each performance, they would
have much less time after buying the tickets to change their minds about whether to attend than would
people who bought all the tickets in advance.
E If anything, this might present an additional di culty for those who bought individual tickets without
advance planning, so it would not help to explain the lower no‐show rate among buyers of individual
tickets.
e correct answer is D.
587
8.6 Critical Reasoning Answer Explanations
584. Although there is no record of poet Edmund Spenser’s parentage, we do know that as a youth Spenser attended the
Merchant Tailors’ School in London for a period between 1560 and 1570. Records from this time indicate that the Merchant
Tailors’ Guild then had only three members named Spenser: Robert Spenser, listed as a gentleman; Nicholas Spenser,
elected the Guild’s Warden in 1568; and John Spenser, listed as a “journeyman cloth‐maker.” Of these, the last was likely
the least af uent of the three—and most likely Edmund’s father, since school accounting records list Edmund as a scholar
who attended the school at a reduced fee.
Which of the following is an assumption on which the argument depends?
(A) Anybody in sixteenth century London who made clothing professionally would have had to be a member of the
Merchant Tailors’ Guild.
(B) The fact that Edmund Spenser attended the Merchant Tailors’ School did not necessarily mean that he planned to
become a tailor.
(C) No member of the Guild could become Guild warden in sixteenth century London unless he was a gentleman.
(D) Most of those whose fathers were members of the Merchant Tailors’ Guild were students at the Merchant Tailors’
School.
(E) The Merchant Tailors’ School did not reduce its fees for the children of the more af uent Guild members.
Argument Construction
Situation Records indicate that the poet Edmund Spenser attended the Merchant Tailors’ School for a
reduced fee as a youth. ere is no record of his parentage, but at the time the Merchant Tailors’
Guild had only three members named Spenser, of whom the least a uent was probably John
Spenser.
Reasoning What must be true in order for the cited facts to support the conclusion that John Spenser was probably
Edmund Spenser’s father? e implicit reasoning is that since Edmund Spenser attended the
Merchant Tailors’ School at a reduced fee, his father must have been poor. And since John Spenser
was probably the poorest of the three men named Spenser in the Merchant Tailors’ Guild, he was
probably Edmund Spenser’s father. is reasoning assumes that only the children of poor parents
had reduced fees at the Merchant Tailors’ School, that the children at the school generally had
fathers in the Merchant Tailors’ Guild, that children in that time and place generally shared their
fathers’ surnames, and that the two other Spensers in the Merchant Tailors’ Guild were not poor
enough for their children to qualify for reduced fees.
A John Spenser, as a tailor and member of the guild, could have been Edmund Spenser’s father even if some
other professional tailors did not belong to the guild and did not have children at the school.
B Although Edmund Spenser became a poet as an adult, he and all his classmates might have attended the
school as children because they planned to become tailors.
C e argument assumes that a Guild’s Warden probably would have been wealthier than a journeyman
cloth‐maker, but that might have been probable even if the Guild’s Warden were not a “gentleman.”
D Even if most children of fathers in the guild did not attend the school, all the children who did attend the
school might have had fathers in the guild.
E Correct. If the school reduced its fees for children of wealthier guild members, then the fact that Edmund
Spenser’s fees were reduced would not provide evidence that his father was the poorest of the three
Spensers in the guild, as the argument requires.
e correct answer is E.
588
GMAT® Offi cial Guide 2018
585. Trancorp currently transports all its goods to Burland Island by truck. The only bridge over the channel separating Burland
from the mainland is congested, and trucks typically spend hours in traf c. Trains can reach the channel more quickly than
trucks, and freight cars can be transported to Burland by barges that typically cross the channel in an hour. Therefore, to
reduce shipping time, Trancorp plans to switch to trains and barges to transport goods to Burland.
Which of the following would be most important to know in determining whether Trancorp’s plan, if implemented, is likely to
achieve its goal?
(A) Whether transportation by train and barge would be substantially less expensive than transportation by truck
(B) Whether there are boats that can make the trip between the mainland and Burland faster than barges can
(C) Whether loading the freight cars onto barges is very time consuming
(D) Whether the average number of vehicles traveling over the bridge into Burland has been relatively constant in
recent years
(E) Whether most trucks transporting goods into Burland return to the mainland empty
Evaluation of a Plan
Situation Transporting goods to Burland Island by truck takes many hours, because the trucks must take
the congested single bridge that reaches the island. Trains can get goods to the channel separating
Burland from the mainland more quickly than trucks can, and the freight cars can then be loaded
onto barges that can cross the channel in an hour. Trancorp plans to reduce shipping time by
switching from trucks to trains and barges.
Reasoning What would it be most important to know in determining whether Trancorp will achieve its goal of
reducing shipping time? Trancorp’s plan could fail to reduce shipping time if there were some
aspect of the new shipping process, involving the trains and the barges, that took more time than
anticipated.
A e goal of Trancorp’s plan is to reduce shipping time. is might lower costs—but whether or not it does
so is not directly relevant to whether or not the plan’s goal is achieved.
B Trancorp’s plan involves the use of barges. If some boats can make the trip between the mainland and
Burland faster than barges can, that might be something to consider for the future, but it has nothing to
do with whether the current plan will reduce shipping time.
C Correct. is statement properly identi es something that would be important in determining whether
Trancorp’s plan for reducing shipping time will achieve its goal—that is, whether loading the freight cars
onto the barges will use up all the time saved by not using trucks.
D Regardless of variation in tra c, the bridge, according to the information provided in the passage, is
congested and typically causes trucking delays. Given this information, the degree of variation is not
helpful in evaluating Transcorp’s plan.
E e state of the trucks returning to the mainland has nothing to do with whether Trancorp’s plan for
reducing shipping time will achieve its goal.
e correct answer is C.
589
8.6 Critical Reasoning Answer Explanations
586. Rainwater contains hydrogen of a heavy form called deuterium. The deuterium content of wood re ects the deuterium
content of rainwater available to trees during their growth. Wood from trees that grew between 16,000 and 24,000 years
ago in North America contains signi cantly more deuterium than wood from trees growing today. But water trapped in
several North American caves that formed during that same early period contains signi cantly less deuterium than rainwater
in North America contains today.
Which of the following, if true, most helps to reconcile the two ndings?
(A) There is little deuterium in the North American caves other than the deuterium in the water trapped there.
(B) Exposure to water after a tree has died does not change the deuterium content of the wood.
(C) Industrialization in North America over the past 100 years has altered the deuterium content of rain.
(D) Trees draw on shallow groundwater from rain that falls during their growth, whereas water trapped in caves may have
fallen as rainwater thousands of years before the caves formed.
(E) Wood with a high deuterium content is no more likely to remain preserved for long periods than is wood with a low
deuterium content.
Argument Construction
Situation In North America, wood from trees that grew 16,000 to 24,000 years ago contains more
deuterium than wood from trees growing today. But water in caves that formed during that same
period contains less deuterium than rainwater contains today.
Reasoning What could explain the puzzling discrepancy between the observed deuterium levels in wood and in
caves? Since the deuterium content of wood from trees re ects the deuterium content of rainwater
available to the trees while they grew, the deuterium levels observed in wood suggests that North
American rainwater contained more deuterium 16,000 to 24,000 years ago than it contains today.
But this conclusion seems at odds with the low deuterium levels in water in caves that formed
16,000 to 24,000 years ago. Several factors might explain the discrepancy: the water in those caves
might not be rainwater from the period when the caves formed; or some natural process might
have altered the deuterium levels in the cave water or the wood; or the wood or caves in which
deuterium levels were measured might be statistically abnormal somehow.
A If the caves had absorbed deuterium out of the rainwater trapped in them, there would probably be
deuterium in the cave walls. So the observation that there is little deuterium in the caves apart from that in
the water eliminates one possible explanation for the oddly low deuterium levels in the cave water.
B is suggests that the deuterium levels in the wood accurately re ect higher deuterium levels in rainwater
that fell 16,000 to 24,000 years ago, but it does not explain why the deuterium levels are so low in water in
the caves that formed then.
C is could explain why deuterium levels in rainwater have changed, but it does not help explain the
discrepancy between the high deuterium levels in the wood and the low deuterium levels in the cave water.
D Correct. If the water in the caves fell as rainwater thousands of years before the caves formed, it may date
from a period when rainwater contained much less deuterium than during the period 16,000 to 24,000
years ago, and much less than today.
E If wood with high deuterium content were more likely to be preserved, then wood from 16,000 to 24,000
years ago might have a high deuterium content even if the rainwater then had a low deuterium content. So
the observation that wood with more deuterium is not more likely to be preserved eliminates one possible
explanation for the discrepancy.
e correct answer is D.
590
GMAT® Offi cial Guide 2018
587. Which of the following most logically completes the argument below?
NowNews , although still the most popular magazine covering cultural events in Kalopolis, has recently suffered a signi cant
drop in advertising revenue because of falling circulation. Many readers have begun buying a competing magazine that, at
50 cents per copy, costs less than NowNews at $1.50 per copy. In order to boost circulation and thus increase advertising
revenue, NowNews’s publisher has proposed making it available at no charge, but this proposal has a serious drawback,
since ________.
(A) Those Kalopolis residents with the greatest interest in cultural events are regular readers of both magazines.
(B) One reason NowNews’s circulation fell was that its competitor’s reporting on cultural events was superior.
(C) The newsstands and stores that currently sell NowNews will no longer carry it if it is being given away forfree.
(D) At present, 10 percent of the total number of copies of each issue of NowNews are distributed free to students on
college campuses in the Kalopolis area.
(E) NowNews’s competitor would begin to lose large amounts of money if it were forced to lower its coverprice.
Argument Construction
Situation NowNews is su ering declines in circulation and advertising revenue due to competition from
a lower‐priced magazine. e publisher proposes o ering NowNews for free to reverse these
declines.
Reasoning What would suggest that the publisher’s proposal will fail to increase circulation and advertising revenue?
e proposal’s intended e ect is simply to increase advertising revenue by increasing circulation.
Any evidence that o ering the magazine for free will not result in more copies being circulated
or will not attract advertisers would therefore be evidence of a drawback in the proposal. So a
statement o ering such evidence would logically complete the argument.
A e fact that certain highly motivated Kalopolis residents still read NowNews even at a cost of $1.50 per
issue leaves open the possibility that providing the magazine free might still boost readership.
B is suggests that improving its cultural reporting might help NowNews increase its circulation, not that
the publisher’s proposal will fail to do so.
C Correct. If the proposal leads newsstands and stores to stop carrying NowNews , circulation and
advertising revenue would probably decline as a result.
D Even if 10 percent of the copies of NowNews are already distributed for free, distributing theremaining
90 percent for free could still increase circulation and advertising revenue as thepublisher intends.
E Forcing a competing magazine to lower its cover price and lose lots of money would be an advantage
rather than a drawback of the proposal, as far as the publisher of NowNews was concerned.
e correct answer is C.
591
8.6 Critical Reasoning Answer Explanations
588. Archaeologist: Researchers excavating a burial site in Cyprus found a feline skeleton lying near a human skeleton. Both
skeletons were in the same sediment at the same depth and equally well‐preserved, suggesting that the feline and human
were buried together about 9,500 years ago. This shows that felines were domesticated around the time farming began,
when they would have been useful in protecting stores of grain from mice.
Which of the following, if true, would most seriously weaken the archaeologist’s argument?
(A) Archaeologists have not found any remains of stores of grain in the immediate vicinity of the burial site.
(B) The burial site in Cyprus is substantially older than any other known burial site in which a feline skeleton and a human
skeleton appear to have been buried together.
(C) Paintings found near the burial site seem to show people keeping felines as domestic companions, but do not show
felines hunting mice.
(D) In Cyprus, there are many burial sites dating from around 9,500 years ago in which the remains of wild animals
appear to have been buried alongside human remains.
(E) Before felines were domesticated, early farmers had no effective way to protect stores of grain from mice.
Argument Evaluation
Situation A human skeleton and a feline skeleton were apparently buried together in Cyprus about 9,500
years ago.
Reasoning What would most strongly suggest that the skeletons do not show that felines were domesticated around
the time farming began? e argument implicitly assumes that farming in Cyprus began around
9,500 years ago, so evidence against that assumption would weaken the argument. e argument
could also be weakened by evidence that felines were domesticated much earlier, that the feline
skeleton was not from a domesticated cat, or that the two skeletons were not actually buried
together around 9,500 years ago.
A Even if archaeologists searched for evidence of a grain store, the fact that no such evidence was found near
the burial site is at best only weak evidence that no grain store existed there or slightly farther away.
B e lack of corroborating evidence from other burial sites would weaken the argument slightly but would
still be compatible with the hypothesis that this site revealed one of the very rst burials of a domesticated
cat.
C is would cast doubt on the hypothesis that cats were domesticated mainly to protect stores ofgrain, but
not on the argument’s conclusion that cats were domesticated around the time farming began.
D Correct. If many wild animals were buried alongside humans in Cyprus around 9,500 years ago, then the
feline skeleton is just as likely to be that of a wild animal than that of a domesticated cat.
E Since this would provide an additional reason why early farmers might have domesticated the local cats, it
would strengthen rather than weaken the argument.
e correct answer is D.
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GMAT® Offi cial Guide 2018
589. The heavy traf c in Masana is a growing drain on the city’s economy—the clogging of the streets of the central business
district alone cost the economy more than $1.2 billion over the past year. In order to address this problem, of cials plan to
introduce congestion pricing, by which drivers would pay to enter the city’s most heavily traf cked areas during the busiest
times of the day.
Which of the following, if true, would most strongly indicate that the plan will be a success?
(A) Approximately one- fth of the vehicles in the central business district are in transit from one side of the city to the
other.
(B) Planners expect that, without congestion pricing, traf c in Masana is likely to grow by 6 percent in the next ve years.
(C) In other urban areas, congestion pricing has strongly encouraged carpooling (sharing of rides by private commuters).
(D) Several studies have shown that a reduction in traf c of 15 percent in Masana could result in 5,500 or more new
jobs.
(E) Over 30 percent of the vehicles in the city’s center are occupied by more than one person.
Evaluation of a Plan
Situation Tra c congestion in Masana has been harming the city’s economy. To address the problem,
o cials plan to make drivers pay to enter the city’s most heavily tra cked areas during the busiest
times of day.
Reasoning What would most strongly suggest that the plan will reduce the harm to Masana’s economy from tra c
congestion? In order to succeed, the plan will have to be implemented and e ectively enforced.
Furthermore, the prices drivers pay will have to be high enough to signi cantly change their
behavior in ways that reduce the amount of tra c congestion in the city. Finally, the economic
bene ts from the reduced tra c congestion will have to substantially outweigh any economically
damaging side e ects of the congestion pricing. Any evidence that any of these conditions will
hold would provide at least some support for the prediction that the plan will succeed.
A is provides no evidence that the congestion pricing would a ect the behavior of either the one- fth of
drivers whose vehicles traverse the city or of the other four- fths of drivers, nor does it give any evidence
that the plan would produce overriding economic bene ts.
B is indicates that the tra c problem will grow worse if the plan is not implemented, but it does not
provide any evidence that the plan will help address the problem.
C Correct. is indicates that similar plans have successfully changed drivers’ behavior in other cities in
a way likely to reduce the number of cars on the road in heavily tra cked areas at busy times of day
without producing harmful economic side e ects. us, it provides evidence that the strategy could also be
successful in Masana.
D Although this suggests that reducing tra c congestion would be economically bene cial, it doesn’t provide
any evidence that the plan will succeed in reducing tra c congestion.
E is suggests that many drivers in the city center are already carpooling, which, if anything, indicates that
the plan will be less able to further a ect those drivers’ behavior and thus could be less e ective than it
might otherwise be.
e correct answer is C.
593
8.6 Critical Reasoning Answer Explanations
590. Economist: The most economically ef cient way to reduce emissions of air pollutants is to tax them in proportion to the
damage they are likely to cause. But in Country Y, many serious pollutants are untaxed and unregulated, and policy makers
strongly oppose new taxes. Therefore, the best way to achieve a reduction in air pollutant emissions in Country Y would be
to institute xed upper limits on them.
Which of the following is an assumption of the economist’s argument?
(A) Policy makers in Country Y oppose all new taxes equally strongly, regardless of any bene ts they may provide.
(B) Country Y’s air pollutant emissions would not fall signi cantly if they were taxed in proportion to the damage they are
likely to cause.
(C) Policy makers in Country Y strongly favor reductions in air pollutant emissions.
(D) Country Y’s policy makers believe that air pollutant emissions should be reduced with maximum economic ef ciency.
(E) Policy makers in Country Y do not oppose setting xed upper limits on air pollutant emissions as strongly as they
oppose new taxes.
Argument Construction
Situation Although taxing air pollution emissions in proportion to the damage they cause is the most
economically e cient way to reduce those emissions, many serious pollutants in Nation Y are
untaxed and unregulated, and the nation’s policy makers strongly oppose new taxes. erefore,
xed upper limits on such emissions would more e ectively reach this goal.
Reasoning What must be true in order for the factors the economist cites to support the claim that xing upper
limits on air pollutant emissions in Nation Y would be the best way to reduce those emissions? Political
opposition to taxation in Nation Y is the only factor the economist cites to support the argument’s
conclusion that it would be best to institute xed upper limits on air pollutants. In order for
the premise to support the conclusion, there must be less political opposition in Nation Y to
instituting such limits than there would be to the proportional taxation approach the economist
prefers.
A Even if the policy makers oppose some new taxes less than others, they could still oppose the proportional
taxation approach strongly enough for it to be utterly infeasible.
B Even if the proportional taxation scheme would signi cantly reduce emissions, it still might not be the
best approach for Nation Y if it would generate too much political opposition to be viable there.
C Even if policy makers in Nation Y do not strongly favor reducing emissions, xing upper limits on
emissions might still be a better and more politically feasible way to reduce emissions than any alternative
is.
D Since xing upper emissions limits would be no more economically e cient than the proportional taxation
scheme, the policy makers’ support for economic e ciency would not make the former approach any more
politically feasible than the latter.
E Correct. If the policy makers opposed xing upper emissions limits as strongly as they oppose new taxes,
then their opposition to new taxes would no longer support the conclusion that xing the emissions limits
is a better way to reduce emissions.
e correct answer is E.
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591. Humans get Lyme disease from infected ticks. Ticks get infected by feeding on animals with Lyme disease, but the ease
of transmission from host animal to tick varies. With most species of host animal, transmission of Lyme disease to ticks
is extremely rare, but white‐footed mice are an exception, readily passing Lyme disease to ticks. And white‐footed mouse
populations greatly expand, becoming the main food source for ticks, in areas where biodiversity is in decline.
The information in the passage most strongly supports which of the following?
(A) In areas where many humans are infected with Lyme disease, the proportion of ticks infected with Lyme disease is
especially high.
(B) Very few animals that live in areas where there are no white‐footed mice are infected with Lyme disease.
(C) Humans are less at risk of contracting Lyme disease in areas where biodiversity is high.
(D) Ticks feed on white‐footed mice only when other host species are not available to them.
(E) The greater the biodiversity of an area, the more likely any given host animal in that area is to pass Lyme disease to
ticks.
Argument Construction
Situation White‐footed mice readily pass Lyme disease to ticks, which pass it to humans. White‐footed
mouse populations expand where biodiversity is declining.
Reasoning What conclusion do the stated facts support? Since declining biodiversity causes white‐footed mouse
populations to increase, and white‐footed mice are especially likely to pass Lyme disease to ticks,
and ticks pass it to humans, declining biodiversity could reasonably be expected to increase the
incidence of Lyme disease in both ticks and humans.
A In areas where many humans are infected with Lyme disease, the total number of ticks may be unusually
high, so even if the number of infected ticks is unusually high, the proportion of infected ticks may not be
unusually high
B Most animals with Lyme disease may get it from sources other than ticks that have fed on infectedmice.
C Correct. If biodiversity is high, then any biodiversity decline that has already begun has likely not yet
reached a point where white‐footed mouse populations have greatly expanded, so the risk of people
contracting Lyme disease is still relatively less than in areas where biodiversity is low and where signi cant
decline in biodiversity has likely already occurred.
D Even if ticks feed on white‐footed mice when few other species are available for them to feed on, they may
also sometimes feed on white‐footed mice when there are many other species for them to feed on.
E e passage suggests that the overall incidence of Lyme disease is probably lower in more biodiverse areas,
so any given host animal in those areas would probably be less likely to pass Lyme disease to a tick.
e correct answer is C.
595
8.6 Critical Reasoning Answer Explanations
592. Many industrialized nations are trying to reduce atmospheric concentrations of carbon dioxide, a gas released by the
burning of fossil fuels. One proposal is to replace conventional cement, which is made with calcium carbonate, by a
new “eco‐cement.” This new cement, made with magnesium carbonate, absorbs large amounts of carbon dioxide when
exposed to the atmosphere. Therefore, using eco‐cement for new concrete building projects will signi cantly help reduce
atmospheric concentrations of carbon dioxide.
Which of the following, if true, most strengthens the argument?
(A) The cost of magnesium carbonate, currently greater than the cost of calcium carbonate, probably will fall as more
magnesium carbonate is used in cement manufacture.
(B) Eco‐cement is strengthened when absorbed carbon dioxide reacts with the cement.
(C) Before the development of eco‐cement, magnesium‐based cement was considered too susceptible to water erosion
to be of practical use.
(D) The manufacture of eco‐cement uses considerably less fossil fuel per unit of cement than the manufacture of
conventional cement does.
(E) Most building‐industry groups are unaware of the development or availability of eco‐cement.
Argument Evaluation
Situation Many nations are trying to reduce atmospheric concentrations of carbon dioxide. One proposed
method is to use a new type of "eco‐cement" that absorbs carbon dioxide from air.
Reasoning What evidence, combined with the cited facts, would most support the prediction that using eco‐cement
will signi cantly help reduce atmospheric concentrations of carbon dioxide? e prediction assumes that
the use of eco‐cement would be an e ective way to reduce carbon dioxide levels. Any evidence
supporting this assumption will support the prediction.
A Since eco‐cement uses magnesium carbonate, the prediction that magnesium carbonate prices will fall
suggests that a potential nancial barrier to widespread eco‐cement use will diminish. However, those
prices may not fall enough to make eco‐cement cost‐competitive with regular cement.
B Even if absorbed carbon dioxide strengthens eco‐cement, the strengthened eco‐cement might still be
much weaker than regular cement and thus might never become widely used, in which case it will not
signi cantly help reduce atmospheric concentrations of carbon dioxide.
C Even if eco‐cement is less susceptible to water erosion than earlier forms of magnesium‐based cement
were, it might still be much more susceptible to water erosion than regular cement is, and thus might never
become widely used.
D Correct. is suggests that manufacturing eco‐cement produces much less carbon dioxide than
manufacturing regular cement does, so it supports the claim that widespread use of eco‐cement would be
an e ective way to reduce carbon dioxide levels.
E If anything, this lack of awareness makes it less likely that eco‐cement will become widely used, which
in turn makes it less likely that eco‐cement will signi cantly help reduce atmospheric concentrations of
carbon dioxide.
e correct answer is D.
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593. Which of the following most logically completes the argument below?
Davison River farmers are currently deciding between planting winter wheat this fall or spring wheat next spring. Winter
wheat and spring wheat are usually about equally pro table. Because of new government restrictions on the use of Davison
River water for irrigation, per acre yields for winter wheat, though not for spring wheat, would be much lower than average.
Therefore, planting spring wheat will be more pro table than planting winter wheat, since ________.
(A) the smaller‐than‐average size of a winter wheat harvest this year would not be compensated for by higher winter
wheat prices
(B) new crops of spring wheat must be planted earlier than the time at which standing crops of winter wheat are ready to
be harvested
(C) the spring wheat that farmers in the Davison River region plant is well adapted to the soil of the region
(D) spring wheat has uses that are different from those of winter wheat
(E) planting spring wheat is more pro table than planting certain other crops, such as rye
Argument Construction
Situation Farmers in the Davison River region must choose between planting winter wheat in the fall and
planting spring wheat next spring. e crops tend to be equally pro table. is year’s winter wheat
crop yield is likely to be lower than average. e spring wheat yield should not be lower than
average. us, for these reasons (plus one that the argument omits), spring wheat will be more
pro table than winter wheat.
Reasoning Which point would logically complete the argument? What would ensure spring wheat’s pro tability
over winter wheat? Since the yield per acre of winter wheat is likely to be lower than usual, there
will most likely be less winter wheat to sell. Winter wheat could match its usual pro tability if the
price farmers receive for it were to rise. If its price does not rise, however, it is unlikely to match its
usual pro tability. It would thus be unlikely to match spring wheat’s pro tability.
A Correct. If this is true, it would mean that smaller‐than‐average winter wheat yields would translate into
lower‐than‐usual pro ts on winter wheat (while spring wheat would be as pro table as winter wheat
would normally be). is would justify the conclusion that spring wheat will be more pro table than
winter wheat.
B is provides support for the idea that farmers must choose between planting winter wheat and planting
spring wheat, but it does not help determine which would be more pro table to plant.
C is does not help explain why spring wheat is likely to be more pro table than winter wheat, because it
gives no information about how well winter wheat is adapted to the soil of the region.
D at spring wheat and winter wheat have di erent uses is not helpful in supporting a conclusion about
which kind of wheat will be more pro table. It might help to know which of their uses are more pro table
than others.
E Since the question is whether it will be more pro table to plant winter wheat or to plant spring wheat, the
fact that spring wheat is more pro table than nonwheat crops is not relevant.
e correct answer is A.
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8.6 Critical Reasoning Answer Explanations
594. Advertisement: When your car’s engine is running at its normal operating temperature, any major brand of motor oil will
protect it about as well as Tuff does. When the engine is cold, it is a different story: Tuff motor oil ows better at lower
temperatures than its major competitors do. So, if you want your car’s engine to have maximum protection, you should use
Tuff.
Which of the following, if true, most strengthens the argument in the advertisement?
(A) Tuff motor oil provides above‐average protection for engines that happen to overheat.
(B) Tuff motor oil is periodically supplied free of charge to automobile manufacturers to use in factory‐new cars.
(C) Tuff motor oil’s share of the engine oil market peaked three years ago.
(D) Tuff motor oil, like any motor oil, is thicker and ows less freely at cold temperatures than at hot temperatures.
(E) Tuff motor oil is manufactured at only one re nery and shipped from there to all markets.
Argument Evaluation
Situation An advertisement argues that since Tu motor oil ows better than its major competitors at low
temperatures and works about as well as they do at normal temperatures, it provides maximum
protection for car engines.
Reasoning What additional evidence would suggest that Tu motor oil provides the best available protection for
car engines? e argument requires the assumptions that no type of motor oil other than the
“major brands” provides superior protection, that owing better at lower temperatures ensures
superior protection at those temperatures, and that Tu protects car engines at least as well as its
competitors do at above‐normal temperatures. Any evidence supporting any of these assumptions
would strengthen the argument.
A Correct. If Tu provides above‐average protection when engines overheat, in addition to the solid
protection it provides at normal and low temperatures, it may well provide the best available protection
overall.
B e company that makes Tu might give automobile manufacturers free motor oil as a promotional
gimmick even if Tu is an inferior product.
C Tu ’s sales might have declined over the past three years because consumers have realized that Tu is an
inferior product.
D e similar responses of Tu and other motor oils to temperature changes do not suggest that Tu
provides better protection overall than those other motor oils do.
E Even if Tu is manufactured at only one re nery, it may still be an inferior product.
e correct answer is A.
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595. The Testament of William Thorpe was published around 1530 as an appendix to Thorpe’s longer Examination. Many
scholars, however, doubt the attribution of the Testament to Thorpe because, whereas the Examination is dated 1406,
the Testament is dated 1460. One scholar has recently argued that the 1460 date be amended to 1409, based on the
observation that when these numbers are expressed as Roman numerals, MCCCCLX and MCCCCIX, it becomes easy to see
how the dates might have become confused through scribal error.
Which of the following, if true, would most support the scholar’s hypothesis concerning the date of the Testament ?
(A) The sole evidence that historians have had that William Thorpe died no earlier than 1460 was the presumed date of
publication of the Testament .
(B) In the preface to the 1530 publication, the editor attributes both works to William Thorpe.
(C) Few writers in fteenth‐century England marked dates in their works using only Roman numerals.
(D) The Testament alludes to a date, “Friday, September 20,” as apparently contemporaneous with the writing of the
Testament , and September 20 fell on a Friday in 1409 but not in 1460.
(E) The Testament contains few references to historical events that occurred later than 1406.
Argument Construction
Situation e Testament of William orpe , dated 1460, was published around 1530 as an appendix to orpe’s
Examination , dated 1406. But when expressed in Roman numerals, 1460 could easily be confused
with 1409.
Reasoning Given the facts cited, what would provide additional evidence that orpe’s Testament dates from
1409 rather than 1460? e scholar’s hypothesis that the work dates from 1409 is based on the
observation that in Roman numerals, 1409 might easily have been improperly transcribed as
1460. is hypothesis could be supported by evidence that the manuscripts were dated in Roman
numerals, or by any independent evidence that 1409 is a more likely date for the Testament than
1460.
A is suggests that scholars have no biographical evidence that the Testament was published in 1460, but
they could still have abundant evidence of other types to support that date, such as the text’s cultural
allusions or references to other works.
B e editor of the 1530 publication could easily have been mistaken about the authorship of one or both
works. And even if the editor were correct, orpe might have lived long enough to write one work in
1406 and the other in 1460.
C is would cast doubt on the scholar’s argument by providing evidence that the original manuscripts were
not dated only in Roman numerals.
D Correct. is provides strong evidence directly supporting the hypothesis that the Testament dates from
1409 speci cally.
E Even if the Testament contained only one reference to a historical event that occurred later than 1406 (for
example, one event in 1459), that reference alone could provide strong evidence that the work dates from
1460 rather than 1409.
e correct answer is D.
599
8.6 Critical Reasoning Answer Explanations
596. To reduce productivity losses from employees calling in sick, Corporation X implemented a new policy requiring employees
to come into work unless they were so sick that they had to go to a doctor. But a year after the policy was implemented, a
study found that Corporation X’s overall productivity losses due to reported employee illnesses had increased.
Which of the following, if true, would best explain why the policy produced the reverse of its intended effect?
(A) After the policy was implemented, employees more frequently went to the doctor when they felt sick.
(B) Before the policy was implemented, employees who were not sick at all often called in sick.
(C) Employees coming into work when sick often infect many of their coworkers.
(D) Unusually few employees became genuinely sick during the year after the policy was implemented.
(E) There are many other factors besides employee illness that can adversely affect productivity.
Evaluation of a Plan
Situation After a company started requiring employees to come to work unless they were sick enough to
have to go to a doctor, the company’s productivity losses from reported employee illness increased.
Reasoning What would explain why the policy increased productivity losses from reported employee illness? Any
factors that could have plausibly caused the policy to increase employee absenteeism from reported
illness or to reduce the employees’ productivity at work as a result of reported illness could explain
why the policy increased productivity losses from reported illness.
A Even though the policy required sick employees to consult a doctor, there is no reason to think that
employees’ doing so would have made them less productive than they would otherwise have been when
absent from work.
B is suggests that the policy made it more di cult for employees to falsely claim illness as an excuse for a
work absence. Reduction in absences should result in productivity gains rather than losses.
C Correct. is could have been a result of the policy and would have led to productivity losses possibly
greater than those seen before the policy was introduced.
D is would help to explain lower productivity losses from reported illness after the policy was
implemented, not higher productivity losses.
E e question is what could explain how the policy increased productivity losses from reported employee
illness speci cally, not productivity losses from any other factors.
e correct answer is C.
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597. Advertising by mail has become much less effective, with fewer consumers responding. Because consumers are
increasingly overwhelmed by the sheer amount of junk mail they receive, most discard almost all offers without considering
them. Thus, an effective way for corporations to improve response rates would be to more carefully target the individuals to
whom they mail advertising, thereby cutting down on the amount of junk mail each consumer receives.
Which of the following, if true, would most support the recommendation above?
(A) There are cost‐effective means by which corporations that currently advertise by mail could improve response rates.
(B) Many successful corporations are already carefully targeting the individuals to whom they mail advertising.
(C) Any consumer who, immediately after receiving an advertisement by mail, merely glances at it is very likely to discard
it.
(D) Improvements in the quality of the advertising materials used in mail that is carefully targeted to individuals can
improve the response rate for such mail.
(E) Response rates to carefully targeted advertisements by mail are considerably higher, on average, than response rates
to most other forms of advertising.
Evaluation of a Plan
Situation Advertising by mail has become less e ective because consumers overwhelmed with the amount of
junk mail they receive discard almost all of it without considering it.
Reasoning What would most help to support the claim that making mail advertising more carefully targeted would
improve response rates? e passage recommends targeted advertising, reasoning that since targeted
advertising would reduce the total amount of junk mail consumers receive, it would generate
higher response rates. Any additional evidence for the claim that carefully targeted advertising
would improve response rates would support this recommendation.
A Even if targeted advertising and every other means of improving response rates were too expensive to be
cost‐e ective, targeted advertising could still be e ective for any corporation willing to pay the expense.
B If many corporations already mail targeted advertising, and mail advertising is nonetheless yielding
declining response rates, that suggests that targeted mail is an ine ective way to increase response rates.
C is could be equally true for targeted and untargeted mail advertising, so it does not suggest that the
former is more e ective.
D e question under consideration is whether more carefully targeted mail advertising would in itself
increase response rates, not whether higher quality advertising would do so.
E Correct. is provides some evidence that carefully targeted mail advertising is associated with higher
response rates than untargeted mail advertising is, and therefore that targeting mail advertising more
carefully would improve response rates.
e correct answer is E.
601
8.6 Critical Reasoning Answer Explanations
598. Petrochemical industry of cials have said that the extreme pressure exerted on plant managers during the last ve
years to improve pro ts by cutting costs has done nothing to impair the industry’s ability to operate safely. However,
environmentalists contend that the recent rash of serious oil spills and accidents at petrochemical plants is traceable to
cost‐cutting measures.
Which of the following, if true, would provide the strongest support for the position held by industry of cials?
(A) The petrochemical industry bene ts if accidents do not occur, since accidents involve risk of employee injury as well
as loss of equipment and product.
(B) Petrochemical industry unions recently demanded that additional money be spent on safety and environmental
protection measures, but the unions readily abandoned those demands in exchange for job security.
(C) Despite major cutbacks in most other areas of operation, the petrochemical industry has devoted more of its
resources to environmental and safety measures in the last ve years than in the preceding ve years.
(D) There is evidence that the most damaging of the recent oil spills would have been prevented had cost‐cutting
measures not been instituted.
(E) Both the large nes and the adverse publicity generated by the most recent oil spill have prompted the petrochemical
industry to increase the resources devoted to oil‐spill prevention.
Argument Evaluation
Situation Petrochemical industry o cials claim that pressure on plant managers to cut costs over the past
ve years has not made the industry’s operations any less safe. Environmentalists claim that recent
oil spills and accidents show otherwise.
Reasoning What evidence would most strongly suggest that the cost‐cutting pressure was not responsible for the
recent rash of oil spills and accidents? Evidence that the plant managers did not cut costs in any
speci c ways likely to have increased the likelihood of oil spills and accidents would support the
industry o cials’ position that the cost‐cutting pressure has not made petrochemical operations
any less safe.
A Even if the petrochemical industry has good reasons to try to prevent accidents, the recent rash of serious
accidents suggests that it is failing to do so and that the cost‐cutting pressure might be responsible.
B is suggests that the unions, whose members could directly observe the cost‐cutting pressure’s e ects,
share the environmentalists’ belief that this pressure contributed to the oil spills and accidents. Because the
unions abandoned their demands, their concerns probably have not been addressed.
C Correct. is suggests that, as the industry o cials claim, the cost‐cutting pressure has not in itself
reduced the industry’s e ectiveness at preventing oil spills and accidents. us, it suggests that other factors
are probably responsible for the recent problems.
D is clearly suggests that the cost‐cutting measures have indeed caused the industry to operate less safely,
as the environmentalists claim.
E Although this suggests that the industry is now trying to address the recent problems, the cost‐cutting
measures might nonetheless have caused all those problems.
e correct answer is C.
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599. Economist: The price of tap water in our region should be raised drastically. Supplies in local freshwater reservoirs
have been declining for years because water is being used faster than it can be replenished. Since the price of tap
water has been low, few users have bothered to adopt even easy conservation measures.
The two sections in boldface play which of the following roles in the economist’s argument?
(A) The rst is a conclusion for which support is provided, and which in turn supports the main conclusion; the second is
the main conclusion.
(B) The rst is an observation for which the second provides an explanation; the second is the main conclusion but not
the only conclusion.
(C) The rst is a premise supporting the argument’s main conclusion; so is the second.
(D) The rst is the only conclusion; the second provides an explanation for the rst.
(E) The rst is the main conclusion; the second is a conclusion for which support is provided, and which in turn supports
the rst.
Argument Construction
Situation Local water supplies have been declining for years because of excessive water use and low prices.
Few users have adopted even easy conservation measures.
Reasoning What roles do the two boldface statements play in the argument? Both are factual observations. Since
no further evidence or support is provided for either, neither can be a conclusion in the argument.
However, interconnected causal explanations, signaled by because and since, are provided for both.
e observation in the rst boldface statement is causally explained by the further observation
that water is being used faster than it can be replenished, which in turn is causally explained by the
entire nal sentence. e observation in the second boldface statement is causally explained by the
observation that the price of tap water has been low. e only remaining portion of the argument
is the initial sentence, a recommendation supported by these four observations together, and by the
causal claims in which they are embedded. us, the four observations (including the two boldface
statements) and the causal claims containing them are all premises, and the initial statement is the
argument’s only conclusion.
A As explained above, the two boldface statements are premises of the argument. Although causal
explanations are provided for both, no support or evidence is provided for either.
B As explained above, the second boldface statement does provide part of the causal explanation for the
observation in the rst boldface statement. But no support is provided for either statement, so neither is a
conclusion.
C Correct. As explained above, each of the statements is a premise that serves along with other claims to
support the recommendation in the initial sentence, which is the argument’s only conclusion, and in that
sense its main conclusion.
D As explained above, the second boldface statement does provide part of the causal explanation for the
observation in the rst boldface statement. But no support is provided for either statement, so neither is a
conclusion in the argument.
E As explained above, the two boldface statements are premises of the argument. Although causal
explanations are provided for both, no support or evidence is provided for either.
e correct answer is C.
603
8.6 Critical Reasoning Answer Explanations
600. Politician: Hybrid cars use signi cantly less fuel per kilometer than nonhybrids. And fuel produces air pollution, which
contributes to a number of environmental problems. Motorists can save money by driving cars that are more fuel ef cient,
and they will be encouraged to drive hybrid cars if we make them aware of that fact. Therefore, we can help reduce the
total amount of pollution emitted by cars in this country by highlighting this advantage of hybrid cars.
Which of the following, if true, would most indicate a vulnerability of the politician’s argument?
(A) People with more fuel‐ef cient cars typically drive more than do those with less fuel‐ef cient cars.
(B) Not all air pollution originates from automobiles.
(C) Hybrid cars have already begun to gain popularity.
(D) Fuel‐ef cient alternatives to hybrid cars will likely become available in the future.
(E) The future cost of gasoline and other fuel cannot be predicted with absolute precision or certainty.
Argument Evaluation
Situation According to a politician, hybrid cars use less fuel per kilometer than nonhybrids, and fuel
produces air pollution. Motorists can save money by driving fuel‐e cient cars, and will be
encouraged to do so if made aware of the fact. e politician concludes that highlighting this fact
will result in a reduction in air pollution.
Reasoning What would suggest that telling motorists they can save money by driving fuel‐e cient cars would
not reduce automotive air pollution, despite the facts cited by the politician? e politician’s implicit
reasoning is that since hybrid cars use less fuel per kilometer, and fuel produces air pollution,
motorists who drive hybrid cars must produce less air pollution than those who drive nonhybrids.
e politician concludes that encouraging motorists to drive hybrid cars by telling them they
would save money on fuel will therefore reduce automotive air pollution. Evidence that motorists
who drive hybrid cars produce just as much automotive air pollution as those who drive
nonhybrids would undermine this argument.
A Correct. If drivers of hybrid cars tend to drive more kilometers than drivers of nonhybrids, then they may
consume just as much fuel and produce just as much air pollution as the nonhybrid car drivers do, despite
their lower fuel use per kilometer.
B e politician’s argument is only about air pollution from cars speci cally, not air pollution from all
sources.
C Even if hybrid cars are beginning to gain popularity, informing motorists of the cost savings from fuel
e ciency could help these cars become more popular than they would otherwise be.
D Encouraging motorists to switch to hybrid cars now could reduce fuel use and automotive air pollution in
the near future even if other, more fuel‐e cient vehicles will become available further in the future.
E Even if the future cost of fuel cannot be predicted accurately, encouraging motorists to switch to hybrid
cars could reduce air pollution as the politician argues.
e correct answer is A.
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601. Which of the following most logically completes the passage?
A recent government study links the high rates of respiratory ailments in Groverston to airborne pollutants released by
the Woodco plywood manufacturing plant there. To address the problem, the government imposed strict regulations on
emissions which will go into effect in four years. Although Woodco plans to cut its emissions in half two years ahead of
schedule, it is unlikely that the rate of respiratory ailments will decline before the regulations go into effect, since ________.
(A) the number of facilities capable of treating respiratory ailments is not likely to increase
(B) reducing emissions even further than planned would necessitate decreasing production at Woodco
(C) it is dif cult to make accurate, long‐term predictions about emissions
(D) not all respiratory ailments are caused by airborne pollutants
(E) three new plywood manufacturing plants are about to go into production in Groverston
Argument Construction
Situation A government study linked high rates of respiratory illness in Groverston to air pollutants released
by a plywood manufacturing plant. A government‐imposed restriction on emissions will go into
e ect in four years. But the Woodco manufacturing plant plans to cut its emissions in half two
years ahead of schedule.
Reasoning Which of the possible completions of the passage will provide the most support for the argument’s
conclusion? e argument’s conclusion is that the rate of respiratory illness is unlikely to decline
before the regulations go into e ect four years from now. at is a surprising claim, given that the
existing plywood factory is going to halve its emissions two years from now—so this claim requires
additional support (to be provided by completing the blank). Such additional support is provided
by the information that three new plywood manufacturing plants will soon be starting production
in Groverston. is suggests that even if Groverston reduces its emissions by half over the next
two years—and even if each of the three new plants have only, let’s say, one quarter of the emissions
of the existing plant as currently operated—the total amount of airborne pollutants from plywood
manufacture in the Groverston area will not decline. Since the total airborne pollution from
the plants will not decline, we should not expect that the rate of respiratory illnesses from such
pollution would decline either.
A e argument focuses on the incidence of respiratory ailments in Groverston, not on the availability
of treatment facilities for such ailments once they occur. So this statement is largely irrelevant to the
argument.
B is information provides no support for the argument’s conclusion. It merely indicates a practical
di culty Woodco would have in making more than a 50 percent reduction in its emissions. However,
even with the 50 percent emissions reduction that Woodco plans to implement in two years, the rate of
respiratory ailments should decline.
C First, it is not clear that a prediction about levels of emissions in Groverston three or four years from now
is a long‐term prediction . More to the point, if it would be very di cult to predict the emissions even two
years from now, that would not support a conclusion that rates of respiratory ailments are unlikely to
decline. Rather, it would support the conclusion that we do not know whether rates will decline.
D is information raises the possibility that within the next four years, an increase in the occurrence of
factors other than airborne pollutants might make a decline in respiratory ailments unlikely. However, the
passage provides no information whatsoever that implies an increase in the occurrence of such “other”
factors.
E Correct. is helps to support the conclusion that rates of respiratory ailments in Groverston are unlikely
to decline before the new government regulations go into e ect.
e correct answer is E.
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8.6 Critical Reasoning Answer Explanations
602. One summer, oods covered low‐lying garlic elds situated in a region with a large mosquito population. Since mosquitoes
lay their eggs in standing water, ooded elds would normally attract mosquitoes, yet no mosquitoes were found in the
elds. Diallyl sul de, a major component of garlic, is known to repel several species of insects, including mosquitoes, so it
is likely that diallyl sul de from the garlic repelled the mosquitoes.
Which of the following, if true, most strengthens the argument?
(A) Diallyl sul de is also found in onions but at concentrations lower than in garlic.
(B) The mosquito population of the region as a whole was signi cantly smaller during the year in which the ooding took
place than it had been in previous years.
(C) By the end of the summer, most of the garlic plants in the ooded elds had been killed by waterborne fungi.
(D) Many insect species not repelled by diallyl sul de were found in the ooded garlic elds throughout the summer.
(E) Mosquitoes are known to be susceptible to toxins in plants other than garlic, such as marigolds.
Argument Evaluation
Situation When summer oods covered garlic elds in an area with many mosquitoes, no mosquitoes were
found in the elds, even though ooded elds would normally attract mosquitoes to lay their eggs
in the water. Diallyl sul de, which is found in garlic, repels mosquitoes and some other insect
species, and likely accounts for the lack of mosquitoes in the area.
Reasoning Given the facts cited, what would provide additional evidence that diallyl sul de from the garlic made
mosquitoes avoid the ooded elds? e argument would be strengthened by any independent
evidence suggesting that diallyl sul de pervaded the ooded elds or excluding other factors that
might explain the absence of mosquitoes in the elds.
A is could strengthen the argument if mosquitoes also avoid ooded onion elds, but we do not know
whether they do.
B is would weaken the argument by suggesting that the general mosquito population decline, rather than
the diallyl sul de, could explain the absence of mosquitoes from the elds.
C It is not clear how this would a ect the amount of diallyl sul de in the ooded elds, so this does not
provide evidence that the diallyl sul de repelled the mosquitoes.
D Correct. is provides evidence that there was no factor other than diallyl sul de that reduced insect
populations in the ooded garlic elds.
E If anything, this would weaken the argument, since it is at least possible that some of these toxins were
present in the ooded elds.
e correct answer is D.
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603. Which of the following most logically completes the passage?
Pecan growers get a high price for their crop when pecans are comparatively scarce, but the price drops sharply when
pecans are abundant. Thus, in high‐yield years, growers often hold back part of their crop in refrigerated warehouses
for one or two years, hoping for higher prices in the future. This year’s pecan crop was the smallest in ve years. It is
nonetheless quite possible that a portion of this year’s crop will be held back, since ________.
(A) each of the last two years produced record‐breaking pecan yields
(B) the quality of this year’s pecan crop is no worse than the quality of the pecan crops of the previous ve years
(C) pecan prices have not been subject to sharp uctuations in recent years
(D) for some pecan growers, this year’s crop was no smaller than last year’s
(E) the practice of holding back part of one year’s crop had not yet become widespread the last time the pecan crop was
as small as it was this year
Argument Construction
Situation e price of pecans tends to drop sharply in years when pecans are abundant. So in high-yield
years, growers often hold back part of the harvest in refrigerated warehouses. is year’s harvest
was the smallest in ve years.
Reasoning What would provide the best completion of the argument? e argument’s conclusion is that some of
this year’s crop might be held back. e blank to be completed should provide a reason in support
of that conclusion. What would lead us to believe that some of this year’s crop might go into cold
storage even though the crop was unusually small? Only in high‐yield years does this usually
happen. But suppose there is already a large quantity of pecans in cold storage from previous
harvests. Given this information, it would make perfect sense to expect that the pecans already in
cold storage would be marketed rst, while some of the latest crop would be stored. is would
avoid the market oversupply and lower producer prices that might result if both all of this year’s
crop and all of the already stored pecans were marketed this year.
A Correct. is answer choice provides information that makes it more probable that the conclusion is true.
B e argument provides no information whatsoever that would suggest the decision to store or not to store
pecans is based on evaluation of the crop’s quality.
C is information is of little or no relevance. It is reasonable to think that predictions about pecan prices
this year would a ect the decision to store or not to store. But the information in this answer choice sheds
little or no light on what this year’s pecan prices might be, given that, as the passage tells us, this year’s crop
is exceptionally small.
D It is not surprising that some growers had crops this year that were as big as their crops the year before.
But what matters, what a ects the price of pecans, is the overall size of total pecan production and the
abundance or scarcity of pecans at the time.
E is piece of history about marketing and storage practices explains why pecans were not placed in storage
in previous small‐yield years, but it provides no reason to believe that some of the new pecan crop will be
stored this year.
e correct answer is A.
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8.6 Critical Reasoning Answer Explanations
604. Coffee shop owner: A large number of customers will pay at least the fair market value for a cup of coffee, even if there is
no formal charge. Some will pay more than this out of appreciation of the trust that is placed in them. And our total number
of customers is likely to increase. We could therefore improve our net cash ow by implementing an honor system in which
customers pay what they wish for coffee by depositing money in a can.
Manager: We’re likely to lose money on this plan. Many customers would cheat the system, paying a very small sum or
nothing at all.
Which of the following, if true, would best support the owner’s plan, in light of the manager’s concern?
(A) The new system, if implemented, would increase the number of customers.
(B) By roasting its own coffee, the shop has managed to reduce the dif culties (and cost) of maintaining an inventory of
freshly roasted coffee.
(C) Many customers stay in the cafe for long stretches of time.
(D) The shop makes a substantial pro t from pastries and other food bought by the coffee drinkers.
(E) No other coffee shop in the area has such a system.
Evaluation of a Plan
Situation e owner and the manager of a co ee shop disagree about whether allowing customers to pay for
co ee on an honor system would increase or decrease pro ts.
Reasoning What would be the best evidence that the honor‐system plan would increase pro ts even if many customers
cheated the system? e owner argues that pro ts would increase because many customers will
choose to pay as much or more than before and the total number of customers will likely increase.
But the manager points out that many customers would also choose to pay little or nothing.
Assuming that the manager is correct about that, what further support could the owner present for
the claim that the plan would still be pro table?
A Since the owner has already basically asserted this, asserting it again would not provide any signi cant
additional support for the plan.
B is suggests that the shop is already pro table, not that the honor‐system plan would make it more
pro table.
C Customers who stay in the cafe for long stretches would not necessarily pay any more per cup on the
honor‐system plan than other customers would.
D Correct. If the customer base increases (as both the owner and the manager seem to agree), more
customers will likely purchase highly pro table pastries and other foods, thus boosting pro ts.
E e reason no other co ee shop in the area has an honor system may be that their owners and managers
have determined that it would not be pro table.
e correct answer is D.
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605. Which of the following most logically completes the argument?
By competing with rodents for seeds, black ants help control rodent populations that pose a public health risk. However, a
very aggressive species of black ant, the Loma ant, which has recently invaded a certain region, has a venomous sting that
is often fatal to humans. Therefore, the planned introduction into that region of ant ies, which prey on Loma ants, would
bene t public health, since ________.
(A) ant ies do not attack black ants other than Loma ants
(B) Loma ants are less effective than many bird species in competing with rodents for seeds
(C) certain other species of black ants are more effective than Loma ants in competing with rodents for seeds
(D) the sting of Loma ants can also be fatal to rodents
(E) some pesticides that could be used to control Loma ants are harmful to the environment
Argument Construction
Situation Black ants help to control populations of rodents by competing with them for seeds. But a very
aggressive species of black ant, the Loma ant, has a sting that can be fatal to humans. Ant ies
prey on Loma ants and their presence can thereby bene t public health.
Reasoning Which of the possible completions of the passage provides the most support for the conclusion? e
argument’s conclusion is that introducing ant ies into the region where Loma ants have recently
invaded would bene t public health. We know from the passage that black ants, generally, bene t
public health by keeping down rodent populations. However, the sting of Loma ants, a species of
black ant, can be fatal to humans. Ant ies prey on Loma ants. To that extent their introduction
in the region would tend to bene t public health by making fatal Loma stinging of humans less
likely. But if these ant ies also prey on black ants other than the Loma ants, then to that extent
they would undermine another public health bene t associated with controlling rodents. us, the
information that ant ies do not prey on black ants other than Loma ants would provide strong
logical support for the conclusion.
A Correct. is most logically completes the argument because it addresses a potential downside of
introducing the ant ies into the region. e potential downside is that it might reduce the desirable e ect
that other species of black ants have in keeping down the rodent populations.
B We have no idea whether the bird species that are more e ective than Loma ants at competing with
rodents for seeds are even present in the region in question.
C is does not help the conclusion very much because we do not know from the passage whether ant ies
prey on other species of black ants besides Loma ants.
D If anything, this is a reason not to introduce ant ies into the region. is answer choice at least suggests
that Loma ants might have some positive e ect on public health because they might keep down rodent
populations by reducing their survival chances.
E is provides very little support for the conclusion. It does not exclude the possibility that there are
pesticides—perhaps several—that would control Loma ants e ectively without harming the environment.
So it is not a strong reason for introducing ant ies.
e correct answer is A.
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8.6 Critical Reasoning Answer Explanations
606. Journalist: In physics journals, the number of articles reporting the results of experiments involving particle accelerators
was lower last year than it had been in previous years. Several of the particle accelerators at major research institutions
were out of service the year before last for repairs, so it is likely that the low number of articles was due to the decline in
availability of particle accelerators.
Which of the following, if true, most seriously undermines the journalist’s argument?
(A) Every article based on experiments with particle accelerators that was submitted for publication last year actually was
published.
(B) The average time scientists must wait for access to a particle accelerator has declined over the last several years.
(C) The number of physics journals was the same last year as in previous years.
(D) Particle accelerators can be used for more than one group of experiments in any given year.
(E) Recent changes in the editorial policies of several physics journals have decreased the likelihood that articles
concerning particle‐accelerator research will be accepted for publication.
Argument Evaluation
Situation A journalist attributes the low number of articles about particle accelerators in physics journals to
the fact that several accelerators at major research institutions had been out of service the previous
year.
Reasoning What point undermines the journalist’s argument? e journalist assumes that the researchers’ lack of
access to the accelerators is responsible for the decline in the number of articles. What else could
explain fewer articles? What if the decline is due, not to the availability of the accelerators for
experiments, but to policies regarding publishing articles related to such experiments? An alternate
explanation is that changes in the editorial policies of physics journals, rather than the e ect of the
out‐of‐service accelerators, could well be responsible for the lower number of published articles
about particle‐accelerator research.
A is statement rules out the possibility that submitted articles were not published, and eliminating this
alternate explanation tends to support the argument.
B A decline in waiting time would seem to promote more articles about accelerator research being written
and published, not fewer.
C While the decline in articles could be explained by a decline in the number of journals, this statement
eliminates that alternate explanation.
D If the accelerators can be used for multiple experiments, then it is reasonable to expect more articles related
to them, not fewer.
E Correct. is statement properly identi es a point that undermines the journalist’s reasoning.
e correct answer is E.
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GMAT® Offi cial Guide 2018
607. Birds have been said to be descended from certain birdlike dinosaur species with which they share distinctive structural
features. The fossil record, however, shows that this cannot be so, since there are bird fossils that are much older than the
earliest birdlike dinosaur fossils that have been found.
Which of the following is an assumption on which the argument relies?
(A) The birdlike dinosaurs have no living descendants.
(B) There are no ightless dinosaur species that have the distinctive structural features shared by birds and birdlike
dinosaurs.
(C) There are no birdlike dinosaur fossils that are older than the bird fossils but have not yet been unearthed.
(D) It could not have been the case that some birds were descended from one of the birdlike dinosaur species and other
birds from another.
(E) Birds cannot have been descended from dinosaur species with which the birds do not share the distinctive structural
features.
Argument Construction
Situation Although birds have been said to be descended from birdlike dinosaurs, some bird fossils predate
the earliest known birdlike dinosaur fossils.
Reasoning What must be true in order for the premise that some bird fossils predate the earliest known birdlike
dinosaur fossils to support the conclusion that birds are not descended from birdlike dinosaurs? e
argument implicitly reasons that since the cited bird fossils predate the earliest known birdlike
dinosaur fossils, they must be from birds that lived before the earliest birdlike dinosaurs, and
which therefore could not have been descended from birdlike dinosaurs. is reasoning assumes
that any birdlike dinosaurs that lived before the rst birds would have left fossils that still exist. It
also assumes that no undiscovered birdlike dinosaur fossils predate the cited bird fossils.
A e argument is only about whether birds are descended from birdlike dinosaurs. Whether birdlike
dinosaurs have any living descendants other than birds is irrelevant.
B e argument is only about birds and birdlike dinosaurs. It is not about other types of dinosaurs that were
not birdlike.
C Correct. If any undiscovered birdlike dinosaur fossils predate the cited bird fossils, then the latter fossils’
age does not support the conclusion that birds are not descended from birdlike dinosaurs.
D e argument purports to establish that the relative ages of bird fossils and birdlike dinosaur fossils
show that birds cannot be descended from any of the known birdlike dinosaur species. In doing this, it
acknowledges multiple birdlike dinosaur species and leaves open the question of whether some birds may
be descended from one such species and other birds from another such species.
E e argument does not claim that the known fossil record shows that birds cannot be descended from
dinosaurs. It only claims that the record shows that they cannot be descended from the birdlike dinosaurs
that shared their distinctive structural features.
e correct answer is C.
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8.6 Critical Reasoning Answer Explanations
608. City council member: Demand for electricity has been increasing by 1.5 percent a year, and there simply is no more space
to build additional power plants to meet future demand increases. We must therefore begin to curtail usage, which is why I
propose passing ordinances requiring energy‐conservation measures in all city departments.
The city council member’s proposal assumes which of the following?
(A) Existing power plants do not have the capacity to handle all of the projected increase in demand for electricity.
(B) No city departments have implemented energy‐conservation measures voluntarily.
(C) Passing ordinances designed to curtail electricity usage will not have negative economic consequences for the city.
(D) Residential consumers are not responsible for the recent increases in demand for electricity.
(E) City departments that successfully conserve energy will set a good example for residential and industrial consumers
of electricity.
Argument Construction
Situation A city council member proposes energy‐conservation measures for all city government
departments because there is no room to build new power plants to meet future increases in the
demand for electricity.
Reasoning What must be true in order for the factors the city council member cites to help justify the proposal? e
city council member says electricity usage must be curtailed on account of an increasing demand
for electricity and a lack of space for new power plants that could meet future demand increases.
In order for this reasoning to help justify the proposal, the cited factors must actually establish a
need to curtail electricity usage.
A Correct. If current power plants could satisfy the projected increased demand for electricity, then
the increasing demand and the lack of room to build new plants would not establish a need to curtail
electricity usage.
B e proposed ordinances could still be necessary even if one city department had voluntarily implemented
energy‐conservation measures.
C Passing the ordinances could still be necessary even if they would have some negative economic e ects.
D No matter who is responsible for the recent increases in demand, curtailing the city government’s
electricity usage could still help to reduce demand.
E Ordinances to curtail the city government’s energy usage could be economically necessary regardless of
whether or not departments that obey the ordinances set a good example.
e correct answer is A.
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609. Which of the following most logically completes the argument below?
Using broad‐spectrum weed killers on weeds that are competing with crops for sunlight, water, and nutrients presents a
dif culty: how to keep the crop from being killed along with the weeds. For at least some food crops, specially treated
seed that produces plants resistant to weed killers is under development. This resistance wears off as the plants mature.
Therefore, the special seed treatment will be especially useful for plants that ________.
(A) produce their crop over an extended period of time, as summer squash does
(B) produce large seeds that are easy to treat individually, as corn and beans do
(C) provide, as they approach maturity, shade dense enough to keep weeds from growing
(D) are typically grown in large tracts devoted to a single crop
(E) are cultivated speci cally for the seed they produce rather than for their leaves or roots
Argument Construction
Situation A di culty in using broad‐spectrum weed killers is keeping them from killing the food crops
along with the weeds. Specially treated seed is being developed that will protect certain food crop
plants in their earlier stages of growth.
Reasoning Which is the best completion for the conclusion? e conclusion is incompletely stated as “ erefore,
the special seed treatment will be especially useful for plants that ________.” e question is what
sorts of plants does the passage suggest the seed treatment would be especially useful for. We have
been told that this treatment makes the plants resistant to weed killer, but that this resistance
wears o when the plant matures. So the treatment will be most useful with plants that are not
harmed by weed killer and that su er no signi cant disadvantage when the resistance wears o as
the plant matures. Choice (C) is the correct answer choice because it describes a sort of plant that
can combat weeds and requires no weed killer once the plant matures.
A Given that the seed treatment wears o as the plant matures, it would not be especially useful for plants
that produce their crops over an extended period.
B We have not been told whether small seeds are more di cult to treat, and so we have no basis to conclude
that the special seed treatment would be especially useful for plants that have large seeds that are easy to
treat individually. We have also been given no reason to think that it is better to treat seeds individually.
C Correct. Plants that, as they approach maturity, produce shade dense enough to keep weeds from growing,
would bene t from resistance to weed killer when young and would not need weed killer when they have
matured and lost their resistance.
D We have been given no reason to think that the seed treatment would be especially useful for plants grown
in a large tract devoted to a single crop. For example, why would it be less useful for small tracts with a
variety of crops?
E A plant harvested for its roots, fruits, or leaves, rather than for its seeds, would derive no less an advantage
from resistance to weed killers in earlier stages of growth.
e correct answer is C.
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8.6 Critical Reasoning Answer Explanations
610. Previously, Autoco designed all of its cars itself and then contracted with specialized parts suppliers to build parts
according to its speci cations. Now it plans to include its suppliers in designing the parts they are to build. Since many
parts suppliers have more designers with specialized experience than Autoco has, Autoco expects this shift to reduce the
overall time and cost of the design of its next new car.
Which of the following, if true, most strongly supports Autoco’s expectation?
(A) When suppliers provide their own designs, Autoco often needs to modify its overall design.
(B) In order to provide designs for Autoco, several of the parts suppliers will have to add to their existing staffs of
designers.
(C) Parts and services provided by outside suppliers account for more than 50 percent of Autoco’s total costs.
(D) When suppliers built parts according to speci cations provided by Autoco, the suppliers competed to win contracts.
(E) Most of Autoco’s suppliers have on hand a wide range of previously prepared parts designs that can readily be
modi ed for a new car.
Evaluation of a Plan
Situation A car manufacturer plans to have its parts suppliers start helping to design the parts they build for
the manufacturer. Many parts suppliers have more designers with specialized experience than the
manufacturer has.
Reasoning What would make it more likely that having the parts suppliers help design the parts will reduce the
time and cost of designing the manufacturer’s next new car? In order for the change to reduce the
time and cost, the parts suppliers involved in designing the next car will probably have to do their
portion of the design process faster and cheaper than the manufacturer would have, and the design
collaboration process will have to avoid producing substantial new ine ciencies.
A e additional need to modify the overall design would probably make the design process slower and more
expensive, not faster and cheaper.
B e additional need to hire more designers would probably increase design costs, not reduce them.
C Although this suggests that the change is likely to substantially a ect the design’s expense, it does not
indicate whether the expense will increase or decrease.
D If anything, this competition probably made Autoco’s previous design process cheaper. It does not suggest
that the new design process, which may involve less competition, will be faster or cheaper than the
previous one.
E Correct. Modifying the previously prepared parts designs will probably be faster and cheaper than
creating new designs from scratch.
e correct answer is E.
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611. In Stenland, many workers have been complaining that they cannot survive on minimum wage, the lowest wage an employer
is permitted to pay. The government is proposing to raise the minimum wage. Many employers who pay their workers the
current minimum wage argue that if it is raised, unemployment will increase because they will no longer be able to afford to
employ as many workers.
Which of the following, if true in Stenland, most strongly supports the claim that raising the minimum wage there will not
have the effects that the employers predict?
(A) For any position with wages below a living wage, the dif culty of nding and retaining employees adds as much to
employment costs as would raising wages.
(B) Raising the minimum wage does not also increase the amount employers have to contribute in employee bene ts.
(C) When in ation is taken into account, the proposed new minimum wage is not as high as the current one was when it
was introduced.
(D) Many employees currently being paid wages at the level of the proposed new minimum wage will demand signi cant
wage increases.
(E) Many employers who pay some workers only the minimum wage also pay other workers wages that are much higher
than the minimum.
Argument Evaluation
Situation Stenland’s government proposes to raise the minimum wage because many workers have
complained they cannot survive on it. But many employers claim that raising the minimum wage
will increase unemployment.
Reasoning What evidence would most strongly suggest that raising the minimum wage will not increase
unemployment? e employers with minimum‐wage workers implicitly reason that because raising
the minimum wage will increase the wages they have to pay each worker, it will reduce the number
of workers they can a ord to employ, and thus will increase unemployment. Evidence that the
increased wage would not actually increase the employers’ expenses per employee would cast doubt
on their prediction, as would evidence that reducing the number of minimum‐wage workers would
not increase the nation’s overall unemployment rate.
A Correct. is suggests that raising the minimum wage would make it easier for employers to nd and
retain minimum‐wage employees, and that the savings would fully o set the cost of paying the higher
wages. If there were such o setting savings, the employers should still be able to a ord to employ as many
workers as they currently do.
B Even if raising the minimum wage does not increase employers’ costs for employee bene ts, paying the
higher wage might still in itself substantially increase employers’ overall costs per employee.
C For all we know, the current minimum wage might have substantially increased unemployment when it
was introduced.
D ese additional demands would probably raise employers’ overall costs per employee, making it more
likely that increasing the minimum wage would increase overall unemployment.
E Even if some workers receive more than the minimum wage, raising that wage could still raise employers’
expenses for employing low‐wage workers, making it too expensive for the employers to employ as many
workers overall.
e correct answer is A.
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8.6 Critical Reasoning Answer Explanations
612. Which of the following most logically completes the argument?
The attribution of the choral work Lacrimae to the composer Pescard (1400–1474) has been regarded as tentative, since
it was based on a single treatise from the early 1500s that named Pescard as the composer. Recently, several musical
treatises from the late 1500s have come to light, all of which name Pescard as the composer of Lacrimae . Unfortunately,
these newly discovered treatises lend no support to the attribution of Lacrimae to Pescard, since ________.
(A) the treatise from the early 1500s misidenti es the composers of some of the musical works it considers
(B) the author of the treatise from the early 1500s had no very strong evidence on which to base the identi cation of
Pescard as the composer of Lacrimae
(C) there are works that can conclusively be attributed to Pescard that are not even mentioned in the treatise from the
early 1500s
(D) the later treatises probably had no source for their attribution other than the earlier treatise
(E) no known treatises from the 1600s identify Pescard as the composer of Lacrimae
Argument Construction
Situation A choral work has been tentatively attributed to Pescard based on a single treatise from the early
1500s. But several treatises from the late 1500s have recently been discovered, and all of them
attribute the work to Pescard.
Reasoning Which of the answer choices provides the strongest reason for the conclusion? e argument’s conclusion
is that the newly discovered late‐1500 treatises lend no support to the attribution of Lacrimae to
Pescard. It is worth noting that prior to the conclusion the passage provides information which
suggests that these newly discovered treatises do lend support to the attribution. So the question
is: Why don’t they? A good reason for thinking they do not is that the newly discovered treatises
probably derive solely from the attribution given in the earlier text. us the attributions in the
later treatises are only as reliable as the attribution in the earlier treatise—and the argument
suggests that that reliability has not been conclusively established.
A is makes the treatise from the early 1500s less reliable, but it does not explain why the newly discovered
treatises are unreliable.
B Like answer choice (A), this is irrelevant. e question is not why the treatise from the early 1500s fails to
lend support to the attribution but why the treatises from the late 1500s fail to do so.
C is is irrelevant because it does not refer to the newly discovered treatises whose attribution of Lacrimae
is at issue.
D Correct. e question is whether these newly discovered treatises lend additional support. Lacrimae
has already been tentatively attributed to Pescard based on the text from the early 1500s. So, if the later
treatises base their attribution solely on the earlier treatise, then they provide no additional support beyond
that already provided by the earlier treatise.
E is leaves open the possibility that there was no treatise at all in the 1600s that discussed Pescard or
Lacrimae . Also, it fails to provide signi cant evidence either for or against Pescard’s having composed
Lacrimae . But even if it did provide such evidence, it would be irrelevant because the issue is why the
late‐1500 treatises fail to provide signi cant support for the attribution of Lacrimae to Pescard, not
whether Pescard composed the work.
e correct answer is D.
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613. When trying to identify new technologies that promise to transform the marketplace, market researchers survey the
managers of those companies that are developing new technologies. Such managers have an enormous stake in
succeeding, so they invariably overstate the potential of their new technologies. Surprisingly, however, market researchers
typically do not survey a new technology’s potential buyers, even though it is the buyers—not the producers—who will
ultimately determine a technology’s commercial success.
Which of the following, if true, best accounts for the typical survey practices among market researchers?
(A) If a new technology succeeds, the commercial bene ts accrue largely to the producers, not to the buyers, of that
technology.
(B) People who promote the virtues of a new technology typically fail to consider that the old technology that is currently
in use continues to be improved, often substantially.
(C) Investors are unlikely to invest substantial amounts of capital in a company whose own managers are skeptical about
the commercial prospects of a new technology they are developing.
(D) The potential buyers for not‐yet‐available technologies can seldom be reliably identi ed.
(E) The developers of a new technology are generally no better positioned than its potential buyers to gauge how rapidly
the new technology can be ef ciently mass‐produced.
Argument Construction
Situation Market researchers seeking to identify new technologies that have the potential to transform the
marketplace survey managers of companies developing new technologies, but typically not the
potential buyers of new technologies, even though managers tend to overstate the potential of
their new technologies and it is the buyers who determine the products’ commercial success.
Reasoning What best explains why it is managers, not buyers, that the market researchers survey? Why, despite the
information in the passage, are managers of technology companies surveyed while potential buyers
are typically not? A partial explanation would be that it is di cult to reliably determine who
the potential buyers of new technologies will be. If market researchers cannot identify who the
potential buyers of as‐yet unavailable technologies will be, that explains why they are not typically
surveyed—and why the next best alternative may be to survey managers.
A is answer choice tells us who would bene t from commercial success of new technologies. But it
says nothing about whose opinion would be most valuable in predicting the commercial success of new
technologies.
B At most, this could help explain why managers overstate the potential of their new technologies. But it
does not explain the motives of market researchers in relying on the managers’ rather than buyers’ opinions
about new technologies.
C Given that managers of technology companies will want to attract investors, this helps to explain why the
managers would tend to overstate the potential of their new technologies. But it does not help to explain
the survey practices.
D Correct. is accounts for why potential buyers of new technologies are not typically sought out in surveys
by market researchers: It is di cult to determine in advance who they are.
E is, like answer choice (C), tends to make the practices of market researchers more di cult rather
than easier to understand. If developers of new technologies are no better at gauging how rapidly a new
technology can be mass‐produced (a factor a ecting commercial success), then all the more reason to
survey potential buyers rather than the managers.
e correct answer is D.
617
8.6 Critical Reasoning Answer Explanations
614. Infotek, a computer manufacturer in Katrovia, has just introduced a new personal computer model that sells for signi cantly
less than any other model. Market research shows, however, that very few Katrovian households without personal
computers would buy a computer, regardless of its price. Therefore, introducing the new model is unlikely to increase the
number of computers in Katrovian homes.
Which of the following is an assumption on which the argument depends?
(A) Infotek achieved the lower price of the new model by using components of lower quality than those used by other
manufacturers.
(B) The main reason cited by consumers in Katrovia for replacing a personal computer is the desire to have an improved
model.
(C) Katrovians in households that already have computers are unlikely to purchase the new Infotek model as an additional
computer for home use.
(D) The price of other personal computers in Katrovia is unlikely to drop below the price of Infotek’s new model in the
near future.
(E) Most personal computers purchased in Katrovia are intended for home use.
Argument Construction
Situation In Katrovia, a new personal computer model costs less than any other model. But market research
shows that very few Katrovian households without personal computers would buy even cheap
ones.
Reasoning What must be true in order for the stated facts to support the conclusion that introducing the new
computer model is unlikely to increase the overall number of computers in Katrovian homes? e market
research supports the conclusion that no new computer model is likely to signi cantly increase the
number of computers in Katrovian homes that currently lack computers. But the overall number of
computers in Katrovian homes will still increase if Katrovian homes that already have computers
buy additional computers while keeping their existing ones. So the argument has to assume that
the new computer model will not increase the number of additional computers purchased for
Katrovian homes that already have computers.
A Even if Infotek used high‐quality components in the new computer model, Katrovians might still refuse to
buy it.
B Replacing a personal computer does not change the overall number of personal computers in homes, so
Katrovians’ motives for replacing their computers are irrelevant to the argument.
C Correct. As explained above, unless computers of the new model are purchased as additional computers
for Katrovian homes that already have computers, the new model’s introduction is unlikely to increase the
overall number of computers in Katrovian homes.
D e assumption that other personal computer prices would stay relatively high does not help establish the
link between its premises and its conclusion. If answer choice D were false, the argument would be no
weaker than it is without any consideration of other computers’ potential prices.
E If most personal computers purchased in Katrovia were not intended for home use, then the new model’s
introduction would be even less likely to increase the number of personal computers in Katrovian homes.
So the argument does not depend on assuming that most of the computers purchased are for home use.
e correct answer is C.
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GMAT® Offi cial Guide 2018
615. Fast‐food restaurants make up 45 percent of all restaurants in Canatria. Customers at these restaurants tend to be young;
in fact, studies have shown that the older people get, the less likely they are to eat in fast‐food restaurants. Since the
average age of the Canatrian population is gradually rising and will continue to do so, the number of fast‐food restaurants is
likely to decrease.
Which of the following, if true, most seriously weakens the argument?
(A) Fast‐food restaurants in Canatria are getting bigger, so each one can serve more customers.
(B) Some older people eat at fast‐food restaurants more frequently than the average young person.
(C) Many people who rarely eat in fast‐food restaurants nevertheless eat regularly in restaurants.
(D) The overall population of Canatria is growing steadily.
(E) As the population of Canatria gets older, more people are eating at home.
Argument Evaluation
Situation In Canatria, the older people get, the less likely they are to eat in fast‐food restaurants. e average
age of Canatrians is increasing.
Reasoning What evidence would most weaken the support provided by the cited facts for the prediction that the
number of fast‐food restaurants in Canatria is likely to decrease? e argument implicitly reasons that
since studies have shown that Canatrians tend to eat in fast‐food restaurants less as they get older,
and since Canatrians are getting older on average, the proportion of Canatrians eating in fast‐food
restaurants will decline. e argument assumes that this means the overall number of fast‐food
restaurant customers will decline and that demand will decrease enough to reduce the number of
fast‐food restaurants that can sustain pro tability. Consequently, fewer new fast‐food restaurants
will open or more old ones will close, or both. us, the number of fast‐food restaurants in
Canatria will fall. Any evidence casting doubt on any inference in this chain of implicit reasoning
will weaken the argument.
A is strengthens the argument by providing additional evidence that the total number of fast‐food
restaurants will decrease. If the average number of customers per fast‐food restaurant is increasing, then
fewer fast‐food restaurants will be needed to serve the same—or a lesser—number of customers.
B Even if a few individuals do not follow the general trends described, those trends could still reduce the
overall demand for and number of fast‐food restaurants.
C e argument is only about fast‐food restaurants, not restaurants of other types.
D Correct. is suggests that even if the proportion of Canatrians eating at fast‐food restaurants declines,
the total number doing so may not decline. us, the total demand for and pro tability of fast‐food
restaurants may not decline either, so the total number of fast‐food restaurants in Canatria may not
decrease.
E If anything, this strengthens the argument by pointing out an additional trend likely to reduce the demand
for, and thus the number of, fast‐food restaurants in Canatria.
e correct answer is D.
619
8.6 Critical Reasoning Answer Explanations
616. In order to withstand tidal currents, juvenile horseshoe crabs frequently burrow in the sand. Such burrowing discourages
barnacles from clinging to their shells. When fully grown, however, the crabs can readily withstand tidal currents without
burrowing, and thus they acquire substantial populations of barnacles. Surprisingly, in areas where tidal currents are very
weak, juvenile horseshoe crabs are found not to have signi cant barnacle populations, even though they seldom burrow.
Which of the following, if true, most helps to explain the surprising nding?
(A) Tidal currents do not themselves dislodge barnacles from the shells of horseshoe crabs.
(B) Barnacles most readily attach themselves to horseshoe crabs in areas where tidal currents are weakest.
(C) The strength of the tidal currents in a given location varies widely over the course of a day.
(D) A very large barnacle population can signi cantly decrease the ability of a horseshoe crab to nd food.
(E) Until they are fully grown, horseshoe crabs shed their shells and grow new ones several times a year.
Argument Construction
Situation Juvenile horseshoe crabs withstand tidal currents by burrowing in the sand. is action makes
barnacles less likely to cling to their shells. Adult horseshoe crabs can withstand currents, so they
do not burrow, and barnacles become more likely to cling to their shells. Surprisingly, however,
juvenile horseshoe crabs that do not burrow, because tidal currents do not threaten them, do not
have signi cant numbers of barnacles clinging to their shells.
Reasoning What would most help explain the nding that nonburrowing juvenile horseshoe crabs do not
have signi cant barnacle populations? e nding suggests that there is some way in which
nonburrowing juvenile horseshoe crabs either discourage barnacles from clinging to their shells,
or get rid of the barnacles that do cling to their shells. Identifying how this is accomplished will
explain the nding.
A is gives a reason why juvenile horseshoe crabs that do not burrow would have signi cant barnacle
populations.
B If barnacles in areas of weak tidal currents readily attach themselves to horseshoe crabs, then it would be
more likely for juvenile horseshoe crabs in such areas to have signi cant barnacle populations.
C e areas under discussion are those where tidal currents are very weak. e strength of currents may vary
widely there, but presumably they are still weak compared to other areas.
D e surprising nding under discussion is why certain juvenile horseshoe crabs do not have signi cant
barnacle populations, despite failing to engage in behavior that dislodges barnacles. at a very large
barnacle population can hurt a horseshoe crab does not help explain such a nding.
E Correct. is statement properly identi es something that helps explain the surprising nding: If juvenile
horseshoe crabs regularly shed their shells, they also regularly shed the barnacles that cling to those shells.
us juvenile horseshoe crabs would most likely be found not to have signi cant barnacle populations.
e correct answer is E.
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617. Last year a chain of fast‐food restaurants, whose menu had always centered on hamburgers, added its rst vegetarian
sandwich, much lower in fat than the chain’s other offerings. Despite heavy marketing, the new sandwich accounts for a
very small proportion of the chain’s sales. The sandwich’s sales would have to quadruple to cover the costs associated with
including it on the menu. Since such an increase is unlikely, the chain would be more pro table if it dropped the sandwich.
Which of the following, if true, most seriously weakens the argument?
(A) Although many of the chain’s customers have never tried the vegetarian sandwich, in a market research survey most
of those who had tried it reported that they were very satis ed with it.
(B) Many of the people who eat at the chain’s restaurants also eat at the restaurants of competing chains and report no
strong preference among the competitors.
(C) Among fast‐food chains in general, there has been little or no growth in hamburger sales over the past several years
as the range of competing offerings at other restaurants has grown.
(D) When even one member of a group of diners is a vegetarian or has a preference for low‐fat food, the group tends to
avoid restaurants that lack vegetarian or low‐fat menu options.
(E) An attempt by the chain to introduce a lower‐fat hamburger failed several years ago, since it attracted few new
customers and most of the chain’s regular customers greatly preferred the taste of the regular hamburgers.
Argument Evaluation
Situation Last year a fast‐food restaurant chain specializing in hamburgers started o ering a low‐fat
vegetarian sandwich and marketed it heavily. e new sandwich’s sales are far too low to cover the
costs associated with including it on the menu.
Reasoning What evidence would most weaken the support provided by the cited facts for the prediction that it
would be more pro table for the chain to drop the sandwich? e implicit argument is that since the
new sandwich’s sales are too low to cover the costs associated with including it on the menu,
o ering the sandwich diminishes the chain’s pro tability and will continue to do so if the
sandwich continues to be o ered. is reasoning assumes that the sandwich provides the chain
no substantial indirect nancial bene ts except through its direct sales. It also assumes that the
sandwich’s sales will not increase su ciently to make the sandwich a viable product. Any evidence
casting doubt on either of these assumptions will weaken the argument.
A is gives information only about the respondents to the survey who had tried the sandwich (possibly very
few), who were probably already more open to liking a vegetarian sandwich than any of the chain’s other
customers. So their responses are probably unrepresentative of the chain’s customers in general and do not
suggest that the sandwich has enough market potential.
B Although the issue of competition with other restaurants is not raised in the information provided, this
new information, if anything, strengthens the argument, by suggesting that the introduction of the new
sandwich has not signi cantly enhanced customer preference for eating at the restaurants that o er the
new sandwich.
C is suggests that the cause of stagnation in fast‐food restaurants’ hamburger sales has been competition
from non‐fast‐food restaurants, but not that the non‐fast‐food restaurants competed by o ering vegetarian
options.
D Correct. is suggests that even if the sandwich’s sales are low, it may indirectly increase the chain’s overall
pro ts by encouraging large groups to eat at the chain.
E is strengthens the argument by suggesting that the chain’s customers are generally not interested in
low‐fat menu options such as the new sandwich.
e correct answer is D.
621
8.6 Critical Reasoning Answer Explanations
618. Transportation expenses accounted for a large portion of the total dollar amount spent on trips for pleasure by residents
of the United States in 1997, and about half of the total dollar amount spent on transportation was for airfare. However,
the large majority of United States residents who took trips for pleasure in 1997 did not travel by airplane but used other
means of transportation.
If the statements above are true, which of the following must also be true about United States residents who took trips for
pleasure in 1997?
(A) Most of those who traveled by airplane did so because the airfare to their destination was lower than the cost of other
available means of transportation.
(B) Most of those who traveled by airplane did so because other means of transportation to their destination were
unavailable.
(C) Per mile traveled, those who traveled by airplane tended to spend more on transportation to their destination than did
those who used other means of transportation.
(D) Overall, people who did not travel by airplane had lower average transportation expenses than people who did.
(E) Those who traveled by airplane spent about as much, on average, on other means of transportation as they did on
airfare.
Argument Construction
Situation In 1997, about half of total transportation spending by U.S. residents taking trips for pleasure was
for airfare. But the large majority of U.S. residents who took trips for pleasure in 1997 did not
travel by airplane.
Reasoning What can be deduced from the stated facts? e information provided indicates that among U.S.
residents who took trips for pleasure in 1997, those who traveled by airplane were a small minority.
Yet this small minority’s spending for airfare accounted for half of all transportation spending
among residents taking trips for pleasure. It follows that on average, those who traveled by airplane
must have spent far more per person on transportation than those who did not travel by airplane.
A is does not follow logically from the information given. Most of those who traveled by airplane may
have done so even if ying was more expensive than other modes of transportation—for example, because
ying was faster or more comfortable.
B is does not follow from the information given. Most of those who traveled by airplane may have done
so even if many other modes of transportation were available—the other modes may all have been less
desirable.
C is does not follow from the information given. ose who traveled by airplane may have traveled much
farther on average than those who used other means of transportation, so their transportation spending per
mile traveled need not have been greater.
D Correct. As explained above, those who traveled by airplane must have spent more per person on
transportation than those who did not travel by airplane, on average. In other words, those who did not
travel by airplane must have had lower average transportation expenses than those who did.
E is does not follow from the information given. Although half the total dollar spending on transportation
was for airfare, much of the transportation spending that was not for airfare was by the large majority of
U.S. residents who did not travel by airplane.
e correct answer is D.
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619. Voters commonly condemn politicians for being insincere, but politicians often must disguise their true feelings when they
make public statements. If they expressed their honest views—about, say, their party’s policies—then achieving politically
necessary compromises would be much more dif cult. Clearly, the very insincerity that people decry shows that our
government is functioning well.
Which of the following, if true, most seriously undermines this reasoning?
(A) Achieving political compromises is not all that is necessary for the proper functioning of a government.
(B) Some political compromises are not in the best long‐term interest of the government.
(C) Voters often judge politicians by criteria other than the sincerity with which they express their views.
(D) A political party’s policies could turn out to be detrimental to the functioning of a government.
(E) Some of the public statements made by politicians about their party’s policies could in fact be sincere.
Argument Evaluation
Situation Politicians must often make insincere public statements because expressing their true feelings
would make it harder for them to achieve politically necessary compromises.
Reasoning What would suggest that the argument’s premises do not establish that politicians’ insincerity shows our
government is functioning well? e implicit reasoning is that insincerity helps politicians achieve
politically necessary compromises, and these compromises help our government to function well,
so insincerity must show that our government is functioning well. Evidence that these necessary
compromises do not ensure that our government functions well would undermine the argument’s
reasoning, as would evidence that politicians’ insincerity has other substantial e ects that hinder
the government’s functioning.
A Correct. If governments may function poorly even when insincerity allows necessary political
compromises to be made, then the argument’s premises do not establish that politicians’ insincerity shows
our government is functioning well.
B e argument does not require that all political compromises help government to function well, only that
politically necessary compromises do.
C Even if voters often judge politicians by criteria other than their sincerity, they may also often decry
politicians’ insincerity, not realizing or caring that such insincerity helps the government function well.
D Even if a political party’s policies impair the government’s functioning, politically necessary compromises
by politicians in that party could improve the government’s functioning.
E Even if politicians sometimes speak sincerely about their party’s policies, their general willingness to be
insincere as needed to achieve politically necessary compromises could be a sign that the government is
functioning well.
e correct answer is A.
623
8.6 Critical Reasoning Answer Explanations
620. To reduce waste of raw materials, the government of Sperland is considering requiring household appliances to be broken
down for salvage when discarded. To cover the cost of salvage, the government is planning to charge a fee, which would
be imposed when the appliance is rst sold. Imposing the fee at the time of salvage would reduce waste more effectively,
however, because consumers tend to keep old appliances longer if they are faced with a fee for discarding them.
Which of the following, if true, most seriously weakens the argument?
(A) Increasing the cost of disposing of an appliance properly increases the incentive to dispose of it improperly.
(B) The fee provides manufacturers with no incentive to produce appliances that are more durable.
(C) For people who have bought new appliances recently, the salvage fee would not need to be paid for a number of
years.
(D) People who sell their used, working appliances to others would not need to pay the salvage fee.
(E) Many nonfunctioning appliances that are currently discarded could be repaired at relatively little expense.
Evaluation of a Plan
Situation A government is considering requiring household appliances to be broken down for salvage when
discarded. To cover the salvage costs, the government plans to charge a fee on appliance sales.
Reasoning What would suggest that charging the fee at the time of salvage would less e ectively reduce waste than
charging the fee at the time of sale would? e argument is that charging the fee at the time of
salvage would reduce waste of raw materials because it would encourage consumers to keep their
appliances longer before salvaging them. is argument could be weakened by pointing out other
factors that might increase waste if the fee is charged at the time of salvage or reduce waste if the
fee is charged at the time of sale.
A Correct. is suggests that charging the fee at the time of salvage rather than the time of sale would
encourage consumers to discard their appliances illegally, thereby increasing waste of raw materials by
reducing the proportion of discarded appliances that are salvaged.
B is factor would remain the same regardless of whether the fee was charged at the time of sale or the
time of salvage.
C is might be a reason for consumers to prefer the fee be charged at the time of salvage rather than the
time of sale, but it does not suggest that charging the fee at the time of salvage would reduce waste less
e ectively.
D is provides an additional reason to expect that charging the fee at the time of salvage would help reduce
waste, so it strengthens rather than weakens the argument.
E is would give consumers an additional reason to keep using their old appliances and postpone paying a
fee at the time of salvage, so it strengthens rather than weakens the argument.
e correct answer is A.
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621. When there is less rainfall than normal, the water level of Australian rivers falls and the rivers ow more slowly. Because
algae whose habitat is river water grow best in slow‐moving water, the amount of algae per unit of water generally increases
when there has been little rain. By contrast, however, following a period of extreme drought, algae levels are low even in
very slow‐moving river water.
Which of the following, if true, does most to explain the contrast described above?
(A) During periods of extreme drought, the populations of some of the species that feed on algae tend to fall.
(B) The more slowly water moves, the more conducive its temperature is to the growth of algae.
(C) When algae populations reach very high levels, conditions within the river can become toxic for some of the other
species that normally live there.
(D) Australian rivers dry up completely for short intervals in periods of extreme drought.
(E) Except during periods of extreme drought, algae levels tend to be higher in rivers in which the ow has been
controlled by damming than in rivers that ow freely.
Argument Construction
Situation When Australian rivers ow slowly due to little rain, algae populations in those rivers increase. But
after periods of extreme drought, algae levels are low even in water moving at speeds that would
normally show population increases.
Reasoning What would explain the contrast between algae levels in slow‐moving water resulting from little rain
and slow‐moving water after a drought? ere must be some di erence between what happens
during periods in which there is simply less rainfall than normal and periods in which there is
extreme drought, a di erence that a ects the algae population.
A is indicates one of the consequences of drought, and slightly suggests that this might be due to a lower
algae level. But it does nothing to explain why algae levels might be lower after a drought.
B is could explain why some rivers that are slow‐moving and have little water might have a high algae
level—but not why the algae level is low in such rivers after a period of drought.
C is explains why levels of other species might be low when algae populations are high, not why algae
populations are high when there is little rain, but low following a period of extreme drought.
D Correct. is statement properly identi es something that helps explain the contrast. According to the
information given, the habitat of the algae under discussion is river water. If the river dries up, the algae
will probably not survive. en after the drought, algae population levels would likely take a while to rise
again.
E is emphasizes that there is a contrast between what happens to algae during periods of extreme drought
and what happens to them at other times, but it does not help explain that contrast.
e correct answer is D.
625
8.6 Critical Reasoning Answer Explanations
622. Increased use of incineration is sometimes advocated as a safe way to dispose of chemical waste. But opponents of
incineration point to the 40 incidents involving unexpected releases of dangerous chemical agents that were reported just
last year at two existing incinerators commissioned to destroy a quantity of chemical waste material. Since designs for
proposed new incinerators include no additional means of preventing such releases, leaks will only become more prevalent
if use of incineration increases.
Which of the following, if true, most seriously weakens the argument?
(A) At the two incinerators at which leaks were reported, staff had had only cursory training on the proper procedures for
incinerating chemical waste.
(B) Other means of disposing of chemical waste, such as chemical neutralization processes, have not been proven safer
than incineration.
(C) The capacity of existing incinerators is suf cient to allow for increased incineration of chemical waste without any
need for new incinerators.
(D) The frequency of reports of unexpected releases of chemical agents at newly built incinerators is about the same as
the frequency at older incinerators.
(E) In only three of the reported incidents of unexpected chemical leaks did the releases extend outside the property on
which the incinerators were located.
Argument Evaluation
Situation Last year, at two chemical waste incinerators, there were forty reported incidents involving
unexpected releases of dangerous chemicals. Designs for proposed new incinerators include no
additional safeguards against such releases. erefore, increased use of incineration will likely make
such releases more prevalent.
Reasoning What would undermine the support provided for the conclusion that leaks will become more prevalent
if more chemical waste is disposed of through incineration? e argument draws a general conclusion
about chemical waste incineration from evidence about only two particular incinerators. is
reasoning would be undermined by any evidence that the leaks at those two incinerators were the
result of something other than insu cient safeguards against such releases.
A Correct. If the sta training at the two incinerators was cursory, then the leaks may have been the results
of sta not knowing how to use safeguards with which the incinerators are equipped that, if properly used,
would have prevented the release of dangerous chemicals. erefore, if sta at newer incinerators will be
better trained, leaks might not become more prevalent even if chemical waste incineration becomes more
common.
B Other chemical waste disposal methods may be safer than incineration even if no one has proven so; and
even if they’re not safer overall, they may involve fewer leaks.
C Continuing to use existing incinerators might well produce just as many leaks as switching to new
incinerators would.
D is suggests that new incinerators produce as many leaks as older incinerators do, a nding that provides
additional evidence that increased incineration even with proposed new incinerators would lead to more
leaks.
E e argument is not about how far the releases from leaks extend, only about how many of them are likely
to occur.
e correct answer is A.
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623. Public health expert: Increasing the urgency of a public health message may be counterproductive . In addition to
irritating the majority who already behave responsibly, it may undermine all government pronouncements on health
by convincing people that such messages are overly cautious . And there is no reason to believe that those who
ignore measured voices will listen to shouting.
The two sections in boldface play which of the following roles in the public health expert’s argument?
(A) The rst is a conclusion for which support is provided, but is not the argument’s main conclusion; the second is an
unsupported premise supporting the argument’s main conclusion.
(B) The rst is a premise supporting the only explicit conclusion; so is the second.
(C) The rst is the argument’s main conclusion; the second supports that conclusion and is itself a conclusion for which
support is provided.
(D) The rst is a premise supporting the argument’s only conclusion; the second is that conclusion.
(E) The rst is the argument’s only explicit conclusion; the second is a premise supporting that conclusion.
Argument Construction
Situation A public health expert argues against increasing the urgency of public health messages by pointing
out negative e ects that may arise from such an increase, as well as by questioning its e cacy.
Reasoning What roles are played in the argument by the two claims in boldface? e rst claim in boldface states
that increasing the urgency of public health messages may be counterproductive. After making
this claim, the public health expert mentions two speci c reasons this could be so: it could
irritate people who already behave responsibly, and it could convince people that all public health
messages are too cautious. ( e latter reason in the second claim in boldface). e phrase [ i ] n
addition to indicates that neither claim in the second sentence is intended to support or explain
the other. However, since each claim in the second sentence gives a reason to believe the claim in
the rst sentence, each independently supports the rst sentence as a conclusion. e word [ a ] nd
beginning the third sentence reveals that its intended role in the argument is the same as that of
the two claims in the second sentence.
A Everything stated after the rst sentence is intended to help support it, so the rst sentence is the
argument’s main conclusion.
B Everything stated after the rst sentence is intended to help support it, so the rst sentence is a conclusion,
not a premise.
C Each of the three claims in the second and third sentences is presented as an independent reason to accept
the general claim in the rst sentence. erefore, nothing in the passage is intended to support the second
statement in boldface as a conclusion.
D Everything stated after the rst sentence is intended to help support it, so the rst sentence is a conclusion,
not a premise.
E Correct. Each of the three claims in the second and third sentences is presented as an independent reason
to accept the general claim in the rst sentence. us, each of those claims is a premise supporting the
claim in the rst sentence as the argument’s only conclusion.
e correct answer is E.
627
8.6 Critical Reasoning Answer Explanations
624. Several industries have recently switched at least partly from older technologies powered by fossil fuels to new
technologies powered by electricity. It is thus evident that less fossil fuel is being used as a result of the operations of
these industries than would have been used if these industries had retained their older technologies.
Which of the following, if true, most strengthens the argument above?
(A) Many of the industries that have switched at least partly to the new technologies have increased their output.
(B) Less fossil fuel was used to manufacture the machinery employed in the new technologies than was originally used to
manufacture the machinery employed in the older technologies.
(C) More electricity is used by those industries that have switched at least partly to the new technologies than by those
industries that have not switched.
(D) Some of the industries that have switched at least partly to the new technologies still use primarily technologies that
are powered by fossil fuels.
(E) The amount of fossil fuel used to generate the electricity needed to power the new technologies is less than the
amount that would have been used to power the older technologies.
Argument Evaluation
Situation Several industries have now switched, at least partly, to technologies using electricity rather than
fossil fuels. us, less fossil fuel will be consumed as a result of the operation of these industries
than otherwise would have been.
Reasoning Which option most strengthens the argument? One way to strengthen an argument is to eliminate or
minimize one of its aws or weaknesses. Because the conclusion is stated in terms of “fossil fuel
consumed as a result of the operation of these industries,” the claim would encompass even any
fossil fuel that might be used to generate the electricity that the newer technologies use. Yet the
premise of the argument does not address this issue. So the argument is strengthened if it turns
out that less fossil fuel was used to produce the electricity than would have been used to power the
older technologies.
A In an indirect way, this option slightly weakens rather than strengthens the argument. For if fossil fuels are
used to produce the electricity now used by the industries and if it is because of these newer technologies
that output has increased, the argument’s conclusion is less likely.
B It does not matter how much fossil fuel was used to manufacture the older technologies originally . at has
no bearing on whether more fossil fuel would have been expended as a result of the continued operation of
the industries if the partial switch to newer technologies had not occurred.
C is is what we would expect, but it in no way strengthens the argument.
D is may seem to weaken the argument by indicating that the switch from older technologies will have
less of an impact on fossil fuel consumption by these industries than we might have assumed. But since the
conclusion makes no claim about how much consumption has been reduced, it is not clear that this option
has any bearing on the strength of the argument one way or the other.
E Correct. is is the option that most strengthens the argument.
e correct answer is E.
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625. The difference in average annual income in favor of employees who have college degrees, compared with those who do
not have such degrees, doubled between 1980 and 1990. Some analysts have hypothesized that increased competition
between employers for employees with college degrees drove up income for such employees.
Which of the following, if true, most seriously undermines the explanation described above?
(A) During the 1980s a growing percentage of college graduates, unable to nd jobs requiring a college degree, took
unskilled jobs.
(B) The average age of all employees increased slightly during the 1980s.
(C) The unemployment rate changed very little throughout most of the 1980s.
(D) From 1980 to 1990 the difference in average income between employees with advanced degrees and those with
bachelor’s degrees also increased.
(E) During the 1980s there were some employees with no college degree who earned incomes comparable to the top
incomes earned by employees with a college degree.
Argument Evaluation
Situation e amount by which average annual income for employees with college degrees exceeds that for
employees without such degrees doubled between 1980 and 1990.
Reasoning What evidence would most strongly suggest that increased competition among employers for employees
with college degrees does not explain the relative increase in those employees’ incomes? Such increased
competition could not explain the relative increase in income for employees with college degrees
if the competition did not actually increase, or if such competition occurred but did not result
in employers paying higher wages or salaries, or if the increase in competition to hire employees
without college degrees was even greater. So evidence that any of those conditions existed would
undermine the analysts’ explanation.
A Correct. is suggests that the supply of college graduates grew relative to employers’ demand for them,
and hence that employers’ competition for college‐educated employees did not actually increase.
B e average age might have increased equally for employees with college degrees and for those without
them, so the increase is not clearly relevant to explaining why the di erence between these two groups’
average incomes grew.
C Even if the overall unemployment rate did not change, competition for college‐educated employees could
have increased while competition for other employees decreased.
D is statement gives information comparing income trends among two groups of those with college
degrees, and is irrelevant to the comparison of income trends for those with college degrees and those
without college degrees.
E Even if there was strong competition and high pay for certain unusual types of employees without college
degrees, increasing competition for employees with college degrees might have explained the overall
growing di erence in average pay between employees with college degrees and those without.
e correct answer is A.
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8.6 Critical Reasoning Answer Explanations
626. Which of the following most logically completes the passage?
According to the last pre-election poll in Whippleton, most voters believe that the three problems government needs to address,
in order of importance, are pollution, crime, and unemployment. Yet in the election, candidates from parties perceived as strongly
against pollution were defeated, while those elected were all from parties with a history of opposing legislation designed to reduce
pollution. These results should not be taken to indicate that the poll was inaccurate, however, since __________.
(A) some voters in Whippleton do not believe that pollution needs to be reduced
(B) every candidate who was defeated had a strong antipollution record
(C) there were no issues other than crime, unemployment, and pollution on which the candidates had signi cant
differences of opinion
(D) all the candidates who were elected were perceived as being stronger against both crime and unemployment than the
candidates who were defeated
(E) many of the people who voted in the election refused to participate in the poll
Argument Construction
Situation A pre-election poll indicated that most voters believed the three problems government needs
to address, in order of importance, are pollution, crime, and unemployment. But in the election,
candidates from parties with a history of opposing anti-pollution legislation beat candidates from
parties perceived as more strongly against pollution.
Reasoning What would most help explain how the poll might have been accurate despite the election results? Since
the poll indicated that voters were most concerned about pollution, it suggested that candidates
from anti-pollution parties would be more likely to be elected, other things being equal—and yet
those candidates were not elected. ere are many possible explanations for this outcome that
are compatible with the poll having been accurate. For example, voters might have been swayed
by the candidates’ personalities, quali cations, or advertising more than by their positions on the
issues. Or some candidates might have convinced voters that their personal positions on the issues
were di erent from those of their parties. Or voters might have chosen candidates based on their
positions on crime and unemployment, considering those issues together more important than
pollution alone. Any statement suggesting that any such factors explained the election results
would logically complete the passage by providing a reason to believe that the poll could have been
accurate despite those results.
A If the number of voters who did not believe that pollution needed to be reduced was large enough to
explain the election results, then the poll was probably inaccurate. So this does not explain how the poll
might have been accurate despite those results.
B is eliminates the possibility that candidates were defeated for having weak antipollution records
con icting with their parties’ antipollution stances, so it eliminates one explanation of how the poll might
have been accurate despite the election results. us, it slightly weakens the conclusion of the argument
instead of providing a premise to support it.
C is eliminates the possibility that di erences of opinion among the candidates on these other issues
might explain the election results, but it does not explain how the poll could have been accurate despite the
election results.
D Correct. e poll indicated that voters believed that the government needs to address crime and
unemployment as well as pollution. So if the poll was accurate, the election outcome might have resulted
from voters considering candidates’ positions on crime and unemployment to be jointly more important
than their positions on pollution.
E If anything, this provides a reason to doubt that the poll accurately re ected voters’ opinions. It does not
explain how the poll might have accurately re ected those opinions despite the election results.
e correct answer is D.
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627. Manufacturing plants in Arundia have recently been acquired in substantial numbers by investors from abroad. Arundian
politicians are proposing legislative action to stop such investment, justifying the proposal by arguing that foreign investors,
opportunistically exploiting a recent fall in the value of the Arundian currency, were able to buy Arundian assets at less than
their true value.
Which of the following, if true, casts the most serious doubt on the adequacy of the Arundian politicians’ justi cation for the
proposed legislation?
(A) The Arundian government originally welcomed the fall in the value of the Arundian currency because the fall made
Arundian exports more competitive on international markets.
(B) Foreign investors who acquired Arundian manufacturing plants generally did so with no intention of keeping and
running those plants over the long term.
(C) Without the recent fall in the value of the Arundian currency, many of the Arundian assets bought by foreign investors
would have been beyond the nancial reach of those investors.
(D) In Concordia, a country broadly similar to Arundia, the share of manufacturing assets that is foreign-controlled is
60 percent higher than it is in Arundia.
(E) The true value of an investment is determined by the value of the pro ts from it, and the low value of the Arundian
currency has depressed the value of any pro ts earned by foreign investors from Arundian assets.
Argument Evaluation
Situation After a recent fall in the value of Arundian currency, foreign investors have been acquiring many
Arundian manufacturing plants. Arundian politicians are proposing legislation to stop such
investment.
Reasoning What would most undermine the Arundian politicians’ justi cation for the proposed legislation? e
politicians are justifying their proposal by claiming that foreign investors have been exploiting the
fall in the currency’s value by buying Arundian assets at less than their true value (whatever that
means). Any evidence that their claim is false or meaningless would undermine their justi cation
for the proposal, as would any evidence that the claim, even if true, does not provide a good reason
to stop the foreign investments.
A is suggests that the foreign investors got a good deal on the manufacturing plants, since it provides
evidence that those plants will now be more competitive and pro table. So, if anything, it supports the
politicians’ justi cation for their proposal rather than undermining it.
B is suggests that the foreign investors generally believe the manufacturing plants are undervalued,
and intend to sell them at a pro t as soon as the currency rises enough. So it supports the politicians’
justi cation for their proposal rather than undermining it.
C is suggests that the recent fall in the currency’s value made Arundian assets cost less than usual for
foreign investors, thus arguably allowing the investors to buy the assets at less than their true value. So, if
anything, it supports the politicians’ justi cation for their proposal rather than undermining it.
D e Arundian politicians might consider the example of Concordia to be a warning of the disaster that
could befall Arundia unless the legislation is enacted. So the situation in Concordia might be cited as
support for the politicians’ justi cation of their proposal.
E Correct. is implies that the fall in the Arundian currency’s value has reduced the true value of Arundian
manufacturing plants and any pro ts they may make, so it undermines the politicians’ claim that the
foreign investors exploited the fall in the currency’s value to acquire the plants for less than their true value.
e correct answer is E.
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8.6 Critical Reasoning Answer Explanations
628. Proposed new safety rules for the Beach City airport would lengthen considerably the minimum time between takeoffs from
the airport. In consequence, the airport would be able to accommodate 10 percent fewer ights than currently use the
airport daily. The city’s operating budget depends heavily on taxes generated by tourist spending, and most of the tourists
come by plane. Therefore, the proposed new safety rules, if adopted, will reduce the revenue available for the operating
budget.
The argument depends on assuming which of the following?
(A) There are no periods of the day during which the interval between ights taking off from the airport is signi cantly
greater than the currently allowed minimum.
(B) Few, if any, of the tourists who use the Beach City airport do so when their main destination is a neighboring
community and not Beach City itself.
(C) If the proposed safety rules are adopted, the reduction in tourist numbers will not result mainly from a reduction in the
number of tourists who spend relatively little in Beach City.
(D) Increasing the minimum time between takeoffs is the only way to achieve necessary safety improvements without a
large expenditure by the city government on airport enhancements.
(E) The response to the adoption of the new safety rules would not include an increase in the number of passengers per
ight.
Argument Construction
Situation Proposed safety rules for a city airport would reduce the number of daily ights the airport can
accommodate. e city’s operating budget depends heavily on taxes generated by tourists, who
mostly come by plane. erefore, adopting the safety rules will result in lower revenue available for
the operating budget.
Reasoning What must be true in order for the cited facts to support the conclusion that the proposed rules would
reduce the revenue for the operating budget? e implicit reasoning is that since the rules would
reduce the number of ights that can be accommodated, they would thereby reduce the number
of tourists arriving by plane, which in turn would reduce the tax revenue that tourist spending
generates for the operating budget. is assumes that the actual number of daily ights would fall
along with the number that the airport can accommodate; that fewer daily ights would mean
fewer people ying into the airport; that fewer people ying into the airport would mean fewer
tourists ying into the airport; that fewer tourists ying into the airport would mean fewer tourists
visiting the city; that fewer tourists visiting the city would mean less taxable spending by tourists;
and that less taxable spending by tourists would mean less revenue overall for the operating
budget.
A Even if ights depart the airport less frequently during some periods of the day, increasing the minimum
time between ights at busy times of day could reduce the total number of daily ights from the airport.
B Even if half the tourists ying into the airport were bound for other nearby towns, the other half could still
spend enough in town to generate lots of revenue for the operating budget.
C It is possible that most tourists spend relatively little in the city, but a few spend a lot. In that case, even if
a reduction in tourist numbers resulted mainly from a declining number of tourists who spend relatively
little, it could also greatly reduce the already small number of tourists who spend a lot.
D is suggests that the proposed rules might be nancially better for the city than any alternative
way to improve safety, whereas the argument’s conclusion is that the proposed rules are nancially
disadvantageous.
E Correct. If adopting the proposed rules would result in a large increase in the number of passengers per
ight, fewer daily ights would not necessarily mean fewer passengers or fewer tourists overall.
e correct answer is E.
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629. The introduction of new drugs into the market is frequently prevented by a shortage of human subjects for the clinical trials
needed to show that the drugs are safe and effective. Since the lives and health of people in future generations may depend
on treatments that are currently experimental, practicing physicians are morally in the wrong when, in the absence of any
treatment proven to be effective, they fail to encourage suitable patients to volunteer for clinical trials.
Which of the following, if true, casts most doubt on the conclusion of the argument?
(A) Many drugs undergoing clinical trials are intended for the treatment of conditions for which there is currently no
effective treatment.
(B) Patients do not share the physician’s professional concern for public health, but everyone has a moral obligation to
alleviate suffering when able to do so.
(C) Usually, half the patients in a clinical trial serve as a control group and receive a nonactive drug in place of the drug
being tested.
(D) An experimental drug cannot legally be made available to patients unless those patients are subjects in clinical trials
of the drug.
(E) Physicians have an overriding moral and legal duty to care for the health and safety of their current patients.
Argument Evaluation
Situation A shortage of human subjects for clinical trials needed to show that new drugs are safe and
e ective often prevents those drugs from being introduced into the market. e lives and health of
future generations may depend on treatments that are now experimental.
Reasoning What would cast doubt on the judgment that doctors are morally obligated to encourage their patients
to volunteer for clinical trials? Note that the argument’s conclusion, unlike its premises, is a moral
judgment. is judgment could be cast into doubt by a moral principle that would be likely to
con ict with it under the conditions described. For example, a principle suggesting that it is
sometimes morally unacceptable for doctors to encourage their patients to volunteer for clinical
trials would also suggest that they are not morally obligated to encourage their patients to
volunteer for clinical trials, since anything morally obligatory must also be morally acceptable.
A If anything, this highlights how important it is to ensure that these drugs undergo clinical trials to bene t
future generations, so it supports rather than casts doubt on the argument’s conclusion.
B is suggests that patients are morally obligated to volunteer for clinical trials to help prevent su ering
in future generations. If anything, this supports the claim that doctors are morally obligated to encourage
their patients to volunteer.
C e clinical trial will probably not harm any patients in the control group, yet their participation will
bene t future generations. So, if anything, this supports the claim that doctors should encourage their
patients to volunteer.
D is legal barrier makes it even more essential for the drugs to undergo clinical trials in order to bene t
patients, so it supports rather than casts doubt on the argument’s conclusion.
E Correct. Since the experimental drugs’ safety is being tested during the trials, the drugs may prove unsafe
for subjects in the trials. If doctors have an overriding moral duty to keep their current patients safe, then it
may be morally unacceptable for them to encourage those patients to volunteer for the trials.
e correct answer is E.
633
8.6 Critical Reasoning Answer Explanations
630. As a construction material, bamboo is as strong as steel and sturdier than concrete. Moreover, in tropical areas bamboo is
a much less expensive construction material than either steel or concrete and is always readily available. In tropical areas,
therefore, building with bamboo makes better economic sense than building with steel or concrete, except where land
values are high.
Which of the following, if true, most helps to explain the exception noted above?
(A) Buildings constructed of bamboo are less likely to suffer earthquake damage than are steel and concrete buildings.
(B) Bamboo is unsuitable as a building material for multistory buildings.
(C) In order to protect it from being damaged by termites and beetles, bamboo must be soaked, at some expense, in a
preservative.
(D) In some tropical areas, bamboo is used to make the scaffolding that is used during large construction projects.
(E) Bamboo growing in an area where land values are increasing is often cleared to make way for construction.
Argument Construction
Situation Bamboo is as strong as steel and sturdier than concrete when used as a construction material. In
tropical areas, bamboo is much less expensive and is always readily available.
Reasoning What explains the exception speci ed in the conclusion? e argument’s conclusion is that in tropical
areas bamboo is a more economical building material than steel or concrete, except where land
values are high . e information in the passage makes clear why bamboo is a more economical
building material in tropical areas than are concrete or steel. So the question is: Why must an
exception be made for areas where land values are high? Multistory buildings are particularly
desirable in areas where land values are high, but bamboo may not be suitable for such buildings.
A is explains why bamboo would be preferable to steel or concrete in tropical areas especially prone to
earthquakes. However, there is no clear connection to be made between areas where land values are high
and areas especially prone to earthquakes.
B Correct. Multistory buildings provide a greater area of oor space for a given site area, and in that sense
are more economical. A single‐story building with the same oor space will occupy a much bigger site, so
the higher the land values, the more likely it is that a multistory building will be built on that land. us,
given this information, bamboo is less suitable for areas where land values are high.
C is undermines, to some extent, the claim that bamboo is an economical building material. But itdoes
nothing to explain why it would be less economical speci cally in areas where land values are high.
D is is irrelevant. Bamboo is used to build sca olding for construction projects and as a building material
for permanent structures. ere is no way to infer from this that bamboo is less economical speci cally in
areas where land values are high.
E e fact that bamboo is cleared from an area to make room for construction in no way implies that
bamboo would not be a suitable and economical building material for the area once it has been cleared.
e correct answer is B.
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631. Newspaper editors should not allow reporters to write the headlines for their own stories. The reason for this is that, while
the headlines that reporters themselves write are often clever, what typically makes them clever is that they allude to little-
known information that is familiar to the reporter but that never appears explicitly in the story itself.
Which of the following, if true, most strengthens the argument?
(A) The reporter who writes a story is usually better placed than the reporter’s editor is to judge what the story’s most
newsworthy features are.
(B) To write a headline that is clever, a person must have suf cient understanding of the story that the headline
accompanies.
(C) Most reporters rarely bother to nd out how other reporters have written stories and headlines about the same events
that they themselves have covered.
(D) For virtually any story that a reporter writes, there are at least a few people who know more about the story’s subject
matter than does the reporter.
(E) The kind of headlines that newspaper editors want are those that anyone who has read a reporter’s story in its entirety
will recognize as clever.
Argument Evaluation
Situation e headlines newspaper reporters write for their own stories are often clever only because they
allude to little-known information that never appears explicitly in the stories themselves.
Reasoning What would most help the argument support the conclusion that newspaper editors should not allow
reporters to write headlines for their own stories? e argument’s only explicit premise is that the
headlines newspaper reporters write for their own stories are often clever only because they allude
to little-known information that never appears explicitly in the stories themselves. In order for
this premise to support the conclusion that newspaper editors should not allow reporters to write
their own headlines, it would be helpful to be given a reason why editors should avoid headlines
alluding to such little-known information.
A is suggests that reporters are likely to write better headlines for their stories than editors are, so it
weakens the argument that editors should not allow reporters to write their own headlines.
B Since a reporter who wrote a story is likely to understand that story well, this does not provide a reason
why editors should not allow reporters to write their own headlines.
C If most reporters did what is suggested, they could perhaps hone their headline-writing skills—unless
almost all reporters are weak in such skills, as suggested in the given information. e fact that they do not
bother to do so may help explain why reporters’ headline-writing skills are weak. An explanation of why
this is so does not provide additional support for the argument’s conclusion.
D e people who know more about a story’s subject matter than the reporter writing the story might be just
as likely to see the cleverness of allusions to little-known information as the reporters are. So, to the extent
that this is relevant at all, it slightly weakens the argument by suggesting that obscurely clever headlines
sometimes function as intended.
E Correct. e argument’s explicit premise suggests that typically a reporter’s headline for his or her own
story cannot be recognized as clever by a reader who has read the whole story. So if editors want headlines
that anyone who has read the accompanying stories would recognize as clever, they have a reason not to let
reporters write the headlines.
e correct answer is E.
635
8.6 Critical Reasoning Answer Explanations
632. Scientists have modi ed feed corn genetically, increasing its resistance to insect pests. Farmers who tried out the
genetically modi ed corn last season applied less insecticide to their corn elds and still got yields comparable to those
they would have gotten with ordinary corn. Ordinary corn seed, however, costs less, and what these farmers saved on
insecticide rarely exceeded their extra costs for seed. Therefore, for most feed‐corn farmers, switching to genetically
modi ed seed would be unlikely to increase pro ts.
Which of the following would it be most useful to know in order to evaluate the argument?
(A) Whether there are insect pests that sometimes reduce feed‐corn yields, but against which commonly used
insecticides and the genetic modi cation are equally ineffective
(B) Whether the price that farmers receive for feed corn has remained steady over the past few years
(C) Whether the insecticides typically used on feed corn tend to be more expensive than insecticides typically used on
other crops
(D) Whether most of the farmers who tried the genetically modi ed corn last season applied more insecticide than was
actually necessary
(E) Whether, for most farmers who plant feed corn, it is their most pro table crop
Argument Evaluation
Situation Farmers who grew feed corn genetically engineered to be pest resistant got yields comparable
to those of farmers growing ordinary feed corn, but did so while using less pesticide. Since the
amount saved on pesticide was rarely in excess of the extra costs for the genetically modi ed corn,
most farmers will probably not increase pro ts by choosing the genetically engineered variety.
Reasoning Which would be most useful to know in evaluating the argument? To answer a question such as this,
one should look for information that would strengthen or weaken the argument. If one had
information that the farmers growing the genetically modi ed corn could have increased their
yields last year at lower cost, this would be helpful in evaluating the argument, because this would
show that the argument is weak.
A It does not matter to the argument whether there are pests against which pesticides and genetic resistance
are equally ine ective, because that is compatible with there being pests against which they are not equally
e ective.
B Whether prices of feed corn go up or down a ects the comparison groups equally.
C e relative cost of insecticides for other crops has no bearing on the argument because the argument is
concerned with only feed corn.
D Correct. is option provides the information that it would be most useful to know in evaluating the
argument. It shows that farmers growing genetically modi ed corn last year could have attained higher
pro ts than they in fact did.
E e argument concerns only the relative pro tability of growing one variety of feed corn versus another.
e correct answer is D.
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633. Debater: The average amount of overtime per month worked by an employee in the manufacturing division of the Haglut
Corporation is 14 hours. Most employees of the Haglut Corporation work in the manufacturing division. Furthermore, the
average amount of overtime per month worked by any employee in the company generally does not uctuate much from
month to month. Therefore, each month, most employees of the Haglut Corporation almost certainly work at least some
overtime.
The debater’s argument is most vulnerable to criticism on which of these grounds?
(A) It takes for granted that the manufacturing division is a typical division of the corporation with regard to the average
amount of overtime its employees work each month.
(B) It takes for granted that if a certain average amount of overtime is worked each month by each employee of the
Haglut Corporation, then approximately the same amount of overtime must be worked each month by each employee
of the manufacturing division.
(C) It confuses a claim from which the argument’s conclusion about the Haglut Corporation would necessarily follow with a
claim that would follow from the argument’s conclusion only with a high degree of probability.
(D) It overlooks the possibility that even if, on average, a certain amount of overtime is worked by the members of some
group, many members of that group may work no overtime at all.
(E) It overlooks the possibility that even if most employees of the corporation work some overtime each month, any one
corporate employee may, in some months, work no overtime.
Argument Evaluation
Situation Most of the employees of the Haglut Corporation work in the manufacturing division, where
employees average 14 hours per month in overtime. e average amount of overtime per month
for employees at Haglut does not uctuate much from month to month.
Reasoning What is the argument’s greatest weakness? e argument’s conclusion is that almost certainly each
month most of the employees of Haglut work at least some overtime. Answer choice (D) identi es
the argument’s greatest weakness because it points out how the conclusion of the argument could
be false even if all of the supporting information were true. For example, it could be that less than
half of the employees work any overtime at all, but those that do work overtime work much more
than 14 hours per month.
A e argument leaves open the possibility that in some divisions of the corporation, the average monthly
overtime of its employees is quite di erent from 14 hours, even if (as the argument states) that average
does not change much from month to month.
B e argument does not assume that there is a monthly amount of overtime worked by each employee of
the manufacturing division equivalent to the company‐wide average monthly overtime per employee.
C is does not identify a weakness that can be detected in the argument. Since the claims mentioned here
are not speci ed, the passage provides no evidence that clearly indicates that this type of confusion is
playing a role in the argument.
D Correct. e argument ignores the possibility that most of the employees of Haglut work no overtime at
all in a particular month—which is quite consistent with the argument’s assertion that the average number
of monthly overtime hours per employee within the manufacturing division is 14.
E e possibility described by this is not overlooked by the argument, because this possibility is consistent
with the conclusion. It could easily be that most employees of the corporation work some overtime each
month—as the conclusion envisions—but that there are always some employees who do not work any
overtime.
e correct answer is D.
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8.6 Critical Reasoning Answer Explanations
634. Proponents of the recently introduced tax on sales of new luxury boats had argued that a tax of this sort would be an
equitable way to increase government revenue because the admittedly heavy tax burden would fall only on wealthy
people and neither they nor anyone else would suffer any economic hardship. In fact, however, 20 percent of the workers
employed by manufacturers of luxury boats have lost their jobs as a direct result of this tax.
The information given, if true, most strongly supports which of the following?
(A) The market for luxury boats would have collapsed even if the new tax on luxury boats had been lower.
(B) The new tax would produce a net gain in tax revenue for the government only if the yearly total revenue that it
generates exceeds the total of any yearly tax-revenue decrease resulting from the workers’ loss of jobs.
(C) Because many people never buy luxury items, imposing a sales tax on luxury items is the kind of legislative action that
does not cost incumbent legislators much popular support.
(D) Before the tax was instituted, luxury boats were largely bought by people who were not wealthy.
(E) Taxes can be equitable only if their burden is evenly distributed over the entire population.
Argument Construction
Situation Proponents of a recently introduced tax on sales of new luxury boats argued that it would be an
equitable way to increase government revenue because the tax would fall only on the wealthy and
cause no economic hardship. But because of the tax, 20 percent of luxury-boat manufacturing
workers have lost their jobs.
Reasoning What conclusion do the statements about the proponents’ argument and the tax’s e ects support? Since the
tax caused many workers to lose their jobs, apparently the proponents were incorrect in asserting
that it would cause no one to su er any economic hardship. us, their justi cation for concluding
that the tax is an equitable way to increase government revenue is factually inaccurate, casting
doubt on that conclusion.
A e passage indicates that the tax directly caused a signi cant decrease (though not necessarily a collapse)
in the market for luxury boats. But the passage contains no evidence about whether such a decrease might
not have occurred if the new tax had been somewhat lower.
B Correct. Since the tax caused the workers to lose their jobs, it might have made the government lose
revenue from payroll taxes that the laid-o workers would have paid if they had kept their jobs. So if the
yearly total revenue generated directly and indirectly by the tax were less than those total yearly payroll
taxes and any other tax revenue that was lost as a result of the tax, the tax would have caused a net loss in
tax revenue.
C e passage contains no information about what types of legislative actions cost, or do not cost, incumbent
legislators popular support.
D Although the passage suggests that some of the tax proponents’ assumptions were wrong, it contains no
information suggesting that those proponents were wrong in thinking that luxury boats are purchased
mainly by wealthy people.
E e passage does not provide any basis for determining what makes a tax equitable or about whether the
luxury boat tax is equitable. e tax’s proponents evidently felt that a tax whose burden falls only on the
wealthy rather than evenly on the entire population can be equitable.
e correct answer is B.
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635. In Wareland last year, 16 percent of licensed drivers under 21 and 11 percent of drivers ages 21–24 were in serious
accidents. By contrast, only 3 percent of licensed drivers 65 and older were involved in serious accidents. These gures
clearly show that the greater experience and developed habits of caution possessed by drivers in the 65-and-older group
make them far safer behind the wheel than the younger drivers are.
Which of the following is an assumption on which the argument depends?
(A) Drivers 65 and older do not, on average, drive very many fewer miles per year than drivers 24 and younger.
(B) Drivers 65 and older do not constitute a signi cantly larger percentage of licensed drivers in Wareland than drivers
ages 18–24 do.
(C) Drivers 65 and older are less likely than are drivers 24 and younger to drive during weather conditions that greatly
increase the risk of accidents.
(D) The difference between the accident rate of drivers under 21 and of those ages 21–24 is attributable to the greater
driving experience of those in the older group.
(E) There is no age bracket for which the accident rate is lower than it is for licensed drivers 65 and older.
Argument Evaluation
Situation Last year in Wareland, a much higher percentage of drivers 24 and under than of drivers 65 and
older were in serious accidents.
Reasoning What must be true for the observation about the accident rates to support the conclusion that the greater
experience and caution of drivers 65 and older make them safer behind the wheel than the younger
drivers? Several factors other than greater experience and caution could explain the lower accident
rate among the older drivers. For example, the older drivers might simply drive much less than the
younger ones, but still get in just as many accidents per mile driven. Or perhaps because the older
drivers are more often retired, their schedules less often lead them to drive at times of day when
accident rates are greater for everyone. Or they might be more likely to live in rural areas with less
tra c and lower accident rates. e argument depends on assuming that none of these factors fully
explains the di erence in accident rates.
A Correct. Although we are given no information about the possible extent of any di erence in average
miles driven, the (somewhat vague) information that drivers 65 and older drive very many fewer miles per
year, on average, than drivers 24 and younger would cast serious doubt on the statistical argument given.
e argument assumes that the di erence in miles driven is not su ciently substantial to undermine the
argument.
B e argument is only about the discrepancy between the percentages of the drivers in two speci c age
groups who were in serious accidents last year. e percentages of licensed drivers who fall in these age
groups are irrelevant.
C Even if drivers 65 and older are just as likely as younger drivers to drive in inclement weather, they may do
so far more carefully than the younger drivers, so the older drivers’ greater experience and caution could
still explain their lower accident rates.
D Even if greater experience does not explain the di erence between the accident rates of the two younger
groups of drivers, it might still explain the di erences between the accident rate of those two younger
groups taken together and that of drivers aged 65 and older.
E e accident rate could be lower for drivers in late middle age than for those 65 and older because drivers
in late middle age are also cautious and experienced, but their re exes and vision tend to be less impaired.
Even if that were true, the experience and caution of the drivers 65 and older might still make them safer
than drivers 24 and under.
e correct answer is A.
639
8.6 Critical Reasoning Answer Explanations
636. In the past the country of Malvernia has relied heavily on imported oil. Malvernia recently implemented a program to convert
heating systems from oil to natural gas. Malvernia currently produces more natural gas each year than it uses, and oil
production in Malvernian oil elds is increasing at a steady pace. If these trends in fuel production and usage continue,
therefore, Malvernian reliance on foreign sources for fuel is likely to decline soon.
Which of the following would it be most useful to establish in evaluating the argument?
(A) When, if ever, will production of oil in Malvernia outstrip production of natural gas?
(B) Is Malvernia among the countries that rely most on imported oil?
(C) What proportion of Malvernia’s total energy needs is met by hydroelectric, solar, and nuclear power?
(D) Is the amount of oil used each year in Malvernia for generating electricity and fuel for transportation increasing?
(E) Have any existing oil‐burning heating systems in Malvernia already been converted to natural‐gas‐burning heating
systems?
Argument Evaluation
Situation Malvernia has relied heavily on imported oil, but recently began a program to convert heating
systems from oil to natural gas. Malvernia produces more natural gas than it uses, so it will
probably reduce its reliance on imported oils if these trends continue.
Reasoning Which option provides the information that it would be most useful to know in evaluating the argument?
In other words, we are looking for the option which—depending on whether it was answered
yes or no—would either most weaken or most strengthen the argument. e argument indicates
that Malvernia will be using less oil for heating and will be producing more oil domestically. But
the conclusion that Malvernia’s reliance on foreign oil will decline, assuming the current trends
mentioned continue, would be seriously undermined if there was something in the works that was
bound to o set these trends, for instance, if it turned out that the country’s need for oil was going
to rise drastically in the coming years.
A Since both counteract the need for imported oil, it makes little di erence to the argument whether
domestic oil production exceeds domestic natural gas.
B Whether there are many countries that rely more on foreign oil than Malvernia would have little impact
on whether Malvernia’s need for foreign oil can be expected to decline.
C Since there is no information in the argument about whether Malvernia can expect an increase or decrease
from these other energy sources, it does not matter how much they now provide.
D Correct. is option provides the information that it would be most useful to know in evaluating the
argument.
E e argument tells us that a program has begun recently to convert heating systems from oil to gas. So,
even if no such conversions have been completed, the argument still indicates that they can be expected to
occur.
e correct answer is D.
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GMAT® Offi cial Guide 2018
637. Exposure to certain chemicals commonly used in elementary schools as cleaners or pesticides causes allergic reactions
in some children. Elementary school nurses in Renston report that the proportion of schoolchildren sent to them for
treatment of allergic reactions to those chemicals has increased signi cantly over the past ten years. Therefore, either
Renston’s schoolchildren have been exposed to greater quantities of the chemicals, or they are more sensitive to them
than schoolchildren were ten years ago.
Which of the following is an assumption on which the argument depends?
(A) The number of school nurses employed by Renston’s elementary schools has not decreased over the past ten years.
(B) Children who are allergic to the chemicals are no more likely than other children to have allergies to other substances.
(C) Children who have allergic reactions to the chemicals are not more likely to be sent to a school nurse now than they
were ten years ago.
(D) The chemicals are not commonly used as cleaners or pesticides in houses and apartment buildings in Renston.
(E) Children attending elementary school do not make up a larger proportion of Renston’s population now than they did
ten years ago.
Argument Construction
Situation Some children have allergic reactions to some of the chemicals commonly used in elementary
schools as cleaners and pesticides. e number of children sent to elementary school nurses in
Renston for allergic reactions to such chemicals has risen signi cantly over the past ten years.
Reasoning What must the argument assume? e argument’s conclusion presents just two alternatives: either
the children are exposed to more of the chemicals than children in earlier years or they are more
sensitive. But there is a third possible explanation for the signi cant increase in school‐nurse visits
that the school nurses have reported: that children are just more inclined to go to the school nurse
when they experience an allergic reaction than were children several years ago. For the conclusion
to follow from its premises, the argument must assume that this is not the correct explanation.
A If the number of elementary school nurses in Renston elementary schools had decreased over the past ten
years, that would in no way explain the rise in the proportion of children reporting to school nurses for
allergic reactions.
B Only school‐nurse visits for allergic reactions to the cleaners and pesticides used in elementary schools
are in question in the argument. Of course there could be school‐nurse visits for allergic reactions to other
things, but that issue does not arise in the argument.
C Correct. is can be seen by considering whether the argument would work if we assume that this were
false, i.e., that a school‐nurse visit is more likely in such cases. As noted above, this provides an alternative
to the two explanations that the conclusion claims are the sole possibilities.
D is does not need to be assumed by the argument. e argument’s conclusion suggests that children may
in recent years have had greater exposure to the chemicals, not that this exposure has occurred exclusively
in the schools. e argument does not rely on this latter assumption.
E e argument does not need to make this assumption. e argument is framed in terms of proportions
of children having school‐nurse visits for certain allergic reactions. How many children there are or what
proportion such children are of Renston’s total population is not directly relevant to the argument.
e correct answer is C.
641
8.6 Critical Reasoning Answer Explanations
638. Normally, the pineal gland governs a person’s sleep‐wake cycle by secreting melatonin in response to the daily cycle of light
and darkness as detected by the eye. Nonetheless, many people who are totally blind due to lesions in the visual cortex of
the brain easily maintain a 24‐hour sleep‐wake cycle. So the neural pathway by which the pineal gland receives information
from the eye probably does not pass through the visual cortex.
For purposes of evaluating the argument it would be most useful to establish which of the following?
(A) Whether melatonin supplements help people who have dif culty maintaining a 24‐hour sleep cycle to establish such a
pattern
(B) Whether the melatonin levels of most totally blind people who successfully maintain a 24‐hour sleep‐wake cycle
change in response to changes in exposure to light and darkness
(C) Whether melatonin is the only substance secreted by the pineal gland
(D) Whether most people who do not have a 24‐hour sleep‐wake cycle nevertheless have a cycle of consistent duration
(E) Whether there are any people with normal vision whose melatonin levels respond abnormally to periods of light and
darkness
Argument Evaluation
Situation Normally, a person’s sleep‐wake cycle is governed by the pineal gland secreting melatonin in
response to the daily cycle of light and darkness as detected by the eye. Yet many people who are
totally blind due to lesions of the visual cortex easily maintain a 24‐hour sleep‐wake cycle.
Reasoning What additional information would be most helpful in evaluating the argument? e argument’s
conclusion is that the neural pathway by which the pineal gland receives information probably
does not pass through the visual cortex. is is suggested by the fact that people without a
well‐functioning visual cortex (e.g., people with a certain type of blindness) can nonetheless
maintain a 24‐hour sleep‐wake cycle. Is it by the pineal gland’s secretion of melatonin that they
do so? e argument tells us that normally (i.e., in sighted people), this is the mechanism for
sleep regulation. But the argument depends on assuming that a similar mechanism is operating
in people who are blind but have well‐regulated sleep cycles. e best choice will be the one that
helps us decide whether that assumption is correct.
A is question would not give us an answer that would help in evaluating the argument. A “no” answer
would not clarify whether the pineal gland‐melatonin mechanism operates in people who are blind. A
“yes” answer would do no better. e question refers only to people who have sleep dysfunctions (which
the argument does not address).
B Correct. Answering this question would provide the most useful information for evaluating the argument.
A “yes” answer would help con rm a key assumption of the argument: that blind people rely on the pineal
gland‐melatonin mechanism for sleep regulation. A “no” answer would help discon rm that assumption.
C Whether or not there are other substances secreted by the pineal gland makes no di erence to the
reasoning. e argument relies on the premise that the pineal gland governs the sleep cycle by secreting
melatonin . For example, if the pineal gland sometimes secreted adrenaline, that would still have no bearing
on the argument.
D e consistency or inconsistency of the duration of some people’s sleep patterns has no relevance to the
reasoning. eir sleep patterns could be due to any of a number of factors.
E is does not help, for there could be sighted people whose melatonin levels respond abnormally simply
because of a pineal‐gland abnormality.
e correct answer is B.
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GMAT® Offi cial Guide 2018
639. In countries where automobile insurance includes compensation for whiplash injuries sustained in automobile
accidents, reports of having suffered such injuries are twice as frequent as they are in countries where
whiplash is not covered . Presently, no objective test for whiplash exists, so it is true that spurious reports of whiplash
injuries cannot be readily identi ed. Nevertheless, these facts do not warrant the conclusion drawn by some commentators
that in the countries with the higher rates of reported whiplash injuries, half of the reported cases are spurious. Clearly,
in countries where automobile insurance does not include compensation for whiplash, people often have little
incentive to report whiplash injuries that they actually have suffered.
In the argument given, the two boldfaced portions play which of the following roles?
(A) The rst is a claim that the argument disputes; the second is a conclusion that has been based on that claim.
(B) The rst is a claim that has been used to support a conclusion that the argument accepts; the second is that
conclusion.
(C) The rst is evidence that has been used to support a conclusion for which the argument provides further evidence;
the second is the main conclusion of the argument.
(D) The rst is a nding whose implications are at issue in the argument; the second is a claim presented in order to
argue against deriving certain implications from that nding.
(E) The rst is a nding whose accuracy is evaluated in the argument; the second is evidence presented to establish that
the nding is accurate.
Argument Evaluation
Situation Reported whiplash injuries are twice as common in countries where car insurance companies
pay compensation for such injuries as they are in countries where insurance companies do not.
Although there is no objective test for whiplash, this does not mean, as some suggest, that half of
the reports of such injuries are fake. It could simply be that where insurance will not pay for such
injuries, people are less inclined to report them.
Reasoning What roles do the two boldfaced portions play in the argument? e rst portion tells us about the
correlation between reported cases of whiplash in countries and the willingness of insurance
companies in those countries to compensate for whiplash injuries. e argument next states that
whiplash is di cult to objectively verify. e argument then asserts that although this last fact,
taken together with the rst boldfaced portion, has led some to infer that over half of the reported
cases in countries with the highest whiplash rates are spurious, such an inference is unwarranted.
e second boldfaced portion then helps to explain why such an inference is not necessarily
warranted by o ering an alternative explanation.
A e claim made in the rst boldfaced portion is never disputed in the argument; at dispute is how to
account for the fact that this claim is true. e second is not the argument’s conclusion.
B In a manner of speaking, perhaps, the argument uses the rst portion to support its conclusion; but there is
no indication that it has been used elsewhere to do so. In any case, the second boldfaced portion is not the
argument’s conclusion.
C e rst has been used to support a conclusion that the argument rejects ; the second boldfaced portion is
not the argument’s conclusion.
D Correct. is option correctly identi es the roles played in the argument by the boldfaced portions.
E e accuracy of the rst boldfaced portion is never questioned in the argument; nor is the second intended
to somehow help show that the rst is accurate. Rather, the argument assumes that the rst portion is
accurate.
e correct answer is D.
643
8.6 Critical Reasoning Answer Explanations
640. Last year Comfort Airlines had twice as many delayed ights as the year before, but the number of complaints from
passengers about delayed ights went up three times. It is unlikely that this disproportionate increase in complaints was
rooted in an increase in overall dissatisfaction with the service Comfort Airlines provides, since the airline made a special
effort to improve other aspects of its service last year.
Which of the following, if true, most helps to explain the disproportionate increase in customer complaints?
(A) Comfort Airlines had more ights last year than the year before.
(B) Last year a single period of unusually bad weather caused a large number of ights to be delayed.
(C) Some of the improvements that Comfort Airlines made in its service were required by new government regulations.
(D) The average length of a ight delay was greater last year than it was the year before.
(E) The average number of passengers per ight was no higher last year than the year before.
Argument Construction
Situation Last year Comfort Airlines had twice as many delayed ights as it did the year before, but three
times as many passenger complaints about delayed ights. e airline made a special e ort to
improve other aspects of its service last year.
Reasoning What could explain why the number of complaints about delayed ights increased disproportionately to
the number of delayed ights last year? In other words, why did the average number of passenger
complaints per delayed ight go up last year? One obvious possibility is that the average number
of passengers per delayed ight was greater last year than it had been the year before. Another is
that the ight delays tended to cause worse problems for passengers last year than they had the
year before, so that on average each delay was more upsetting for the passengers.
A is helps explain why the airline had more delayed ights last year, but not why the increase in
complaints about delayed ights was disproportionate to the increase in delayed ights.
B is helps explain why the airline had more delayed ights last year. But, if anything, the situation should
have reduced the number of passenger complaints per delayed ight, since many passengers should have
realized that the unusually bad weather was not the airline’s fault.
C If any of the improvements concerned handling of ight delays, for example, and passengers were aware
that government regulations addressed this, then passengers might have complained more than previously.
But the information we are given here is too general and too vague to explain the disproportionate increase
in complaints.
D Correct. Longer ight delays would have more severely inconvenienced passengers and thus would
probably have generated more passenger complaints per delay.
E is rules out the possibility that an increased number of passengers per delayed ight could have caused
the disproportionate increase in the number of complaints about delayed ights. But no alternative
explanation is o ered.
e correct answer is D
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GMAT® Offi cial Guide 2018
641. Last year a global disturbance of weather patterns disrupted harvests in many of the world’s important agricultural areas.
Worldwide production of soybeans, an important source of protein for people and livestock alike, was not adversely
affected, however. Indeed, last year’s soybean crop was actually slightly larger than average. Nevertheless, the weather
phenomenon is probably responsible for a recent increase in the world price of soybeans.
Which of the following, if true, provides the strongest justi cation for the attribution of the increase in soybean prices to the
weather phenomenon?
(A) Last year’s harvest of anchovies, which provide an important protein source for livestock, was disrupted by the
effects of the weather phenomenon.
(B) Most countries that produce soybeans for export had above‐average harvests of a number of food crops other than
soybeans last year.
(C) The world price of soybeans also rose several years ago, immediately after an earlier occurrence of a similar global
weather disturbance.
(D) Heavy rains attributable to the weather phenomenon improved grazing pastures last year, allowing farmers in many
parts of the world to reduce their dependence on supplemental feed.
(E) Prior to last year, soybean prices had been falling for several years.
Argument Construction
Situation A weather disturbance last year disrupted harvests worldwide but did not reduce production of
soybeans, a protein source for both people and livestock. Soybean prices increased nonetheless,
likely a result of the weather.
Reasoning What evidence would suggest that the weather disturbance caused the increase in soybean prices even
though it did not reduce soybean production? Prices tend to increase when the supply of a product
falls relative to the demand for the product. But the production of soybeans did not fall. Evidence
that the weather disturbance either hindered the global distribution of soybeans or increased
global demand for soybeans could support the claim that the weather disturbance caused the
increase in soybean prices.
A Correct. If the weather disturbance reduced the anchovy harvest, and anchovies provide protein for
livestock just as soybeans do, then more soybeans for livestock feed would be needed to compensate for the
lack of anchovies. e resulting increase in demand for soybeans could thus have increased global soybean
prices.
B is is not surprising, given that the weather disturbance did not severely a ect the soybean‐producing
countries, but it does not explain how the weather disturbance could have caused soybean prices to
increase.
C e rise in soybean prices after the earlier weather disturbance could easily have been a coincidence. Or,
unlike last year’s disturbance, the earlier disturbance could have reduced soybean production.
D is suggests that demand for soybeans should have fallen as a result of the weather disturbance, so it does
not explain why soybean prices rose.
E If soybean prices were unusually low for some temporary reason when the weather disturbance occurred,
they might have been likely to rise back to normal levels even without the weather disturbance.
e correct answer is A.
645
8.6 Critical Reasoning Answer Explanations
642. Most of the year, the hermit thrush, a North American songbird, eats a diet consisting mainly of insects, but in autumn, as
the thrushes migrate to their Central and South American wintering grounds, they feed almost exclusively on wild berries.
Wild berries, however, are not as rich in calories as insects, yet thrushes need to consume plenty of calories in order to
complete their migration. One possible explanation is that berries contain other nutrients that thrushes need for migration
and that insects lack.
Which of the following, if true, most seriously calls into question the explanation given for the thrush’s diet during migration?
(A) Hermit thrushes, if undernourished, are unable to complete their autumn migration before the onset of winter.
(B) Insect species contain certain nutrients that are not found in wild berries.
(C) For songbirds, catching insects requires the expenditure of signi cantly more calories than eating wild berries does.
(D) Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.
(E) There are some species of wild berries that hermit thrushes generally do not eat, even though these berry species
are exceptionally rich in calories.
Argument Evaluation
Situation Hermit thrushes are songbirds that usually eat insects but switch to eating berries when migrating.
e thrushes need lots of calories to migrate, but berries contain fewer calories than insects do.
Perhaps the berries contain nutrients that insects do not provide.
Reasoning What would cast doubt on the claim that the thrushes switch to berries because berries contain nutrients
that insects lack and that the thrushes need for their migration? Evidence that berries do not contain
such nutrients or that thrushes do not decrease their net calorie consumption by eating berries
would cast doubt on the proposed explanation. So would any evidence that supported an
alternative explanation for the diet change during migration—for example, seasonal or regional
di erences in the amount or quality of berries or insects available for the thrushes to consume.
A Even if thrushes need to be well‐nourished to nish migrating before winter, extra nutrients found in
berries but not insects might help provide the nourishment they need.
B Even if insects contain certain nutrients not found in wild berries, those speci c nutrients may not be the
ones the thrushes need for their migration.
C Correct. is suggests that the thrushes might gain more net calories from eating berries than from eating
insects, which could explain why they switch to eating berries even if the berries contain no extra nutrients.
D By ruling out a lack of insects to eat while migrating as an alternative explanation for why the thrushes
switch to eating berries, this would support the proposed explanation.
E e calorie‐rich species of berries the thrushes do not eat might be poisonous or indigestible for them,
even if the species of berries the thrushes do eat contain nutrients they need to migrate.
e correct answer is C.
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GMAT® Offi cial Guide 2018
643. The kinds of hand and wrist injuries that result from extended use of a computer while maintaining an incorrect posture
are common among schoolchildren in Harnville. Computers are important to the school curriculum there, so instead
of reducing the amount their students use computers, teachers plan to bring about a sharp reduction in the number of
these injuries by carefully monitoring their students’ posture when using computers in the classroom.
Which of the following would it be most useful to know in order to assess the likelihood that the teachers’ plan will be
successful?
(A) Whether extended use of a computer while maintaining incorrect posture can cause injuries other than hand and wrist
injuries
(B) Whether hand and wrist injuries not caused by computer use are common among schoolchildren in Harnville
(C) What proportion of schoolchildren in Harnville with hand and wrist injuries use computers extensively outside the
classroom
(D) Whether changes in the curriculum could reduce the schools’ dependence on computers
(E) What proportion of schoolchildren in Harnville already use correct posture while using a computer
Evaluation of a Plan
Situation Hand and wrist injuries from using computers while maintaining poor posture are common
among schoolchildren in Harnville. Teachers plan to greatly reduce the number of such injuries by
monitoring their students’ posture while the students use computers in the classroom.
Reasoning What would be most helpful to know to determine the likelihood that the teachers’ plan will succeed? e
primary concern is the posture students adopt while using computers. To succeed, the teachers’
plan must reduce the time students spend with poor posture while using computers and reduce it
enough to greatly reduce the number of injuries. To know how likely this is, it would help to know
how e ectively the teachers will be able to monitor and improve their students’ posture inside the
classroom. But how many of the students use computers outside of school while maintaining poor
posture and how often do they do so? If many students do so quite often, they may develop hand
and wrist injuries regardless of what happens in school.
A e teachers do not plan to reduce any injuries other than hand and wrist injuries, so whether computer
use with poor posture causes any such other injuries is irrelevant to the likelihood that their plan will
produce its intended e ect.
B e plan being discussed concerns only the reduction of hand and wrist injuries caused speci cally by
computer use with poor posture, so the frequency of hand and wrist injuries from other causes is irrelevant
to the likelihood that the plan will produce its intended e ect.
C Correct. If the students’ school use of computers is a large part of their overall computer use, any retraining that
accompanies the monitoring might have some e ect on their posture and related injury rates overall. However,
the greater the proportion of children with hand and wrist injuries who use computers extensively outside the
classroom, the more children are likely to keep developing the injuries regardless of any monitoring at school, so
the less e ective the teachers’ plan involving only computer use at school is likely to be.
D Knowing whether this is the case might help in developing a potential alternative to the teachers’ plan, but
if it did, this would not help signi cantly toward assessing the likelihood that the actual plan will succeed.
e teachers’ actual plan involves monitoring computer use in school without reducing such use. Other
possible means of achieving the plan’s goal are not part of the plan and are therefore irrelevant to the
likelihood that the teachers’ actual plan will succeed.
E e passage indicates that the proportion of the schoolchildren maintaining poor posture while using
computers is high enough for many to develop hand and wrist injuries as a result. Whatever the exact
proportion is, the teachers’ plan may or may not succeed in reducing it.
e correct answer is C.
647
8.6 Critical Reasoning Answer Explanations
644. A certain cultivated herb is one of a group of closely related plants that thrive in soil with high concentrations of metals
that are toxic to most other plants. Agronomists studying the growth of this herb have discovered that it produces large
amounts of histidine, an amino acid that, in test‐tube solutions, renders these metals chemically inert. Hence, the herb’s
high histidine production must be the key feature that allows it to grow in metal‐rich soils.
In evaluating the argument, it would be most important to determine which of the following?
(A) Whether the herb can thrive in soil that does not have high concentrations of the toxic metals
(B) Whether others of the closely related group of plants also produce histidine in large quantities
(C) Whether the herb’s high level of histidine production is associated with an unusually low level of production of some
other amino acid
(D) Whether growing the herb in soil with high concentrations of the metals will, over time, reduce their concentrations in
the soil
(E) Whether the concentration of histidine in the growing herb declines as the plant approaches maturity
Argument Evaluation
Situation A certain herb and closely related species thrive in soil full of metals toxic to most plants. e
herb produces much histidine, which makes those metals chemically inert. Histidine production,
therefore, is largely what accounts for the herb’s thriving in metal‐rich soils.
Reasoning What evidence would help determine whether the herb’s histidine production is what enables it to thrive
in metal‐rich soils? e argument is that since the herb’s histidine chemically neutralizes the
metals that are toxic to most plants, it must explain why the herb can thrive in metal‐rich soils. To
evaluate this argument, it would be helpful to know about the relationship between other closely
related plant species’ histidine production and the ability to thrive in metal‐rich soils. It would also
be helpful to know about any other factors that might plausibly explain why the herb can thrive in
those soils.
A Whether or not the herb thrives in metal‐free soils, histidine production could enable it to thrive in soils
that contain toxic metals.
B Correct. If the closely related plants do not produce much histidine, whatever other factor allows them to
thrive in metal‐rich soils would likely account for why the herb thrives in those soils as well.
C e given information suggests no particular reason to suppose that a low level of some unspeci ed amino
acid would enable a plant to thrive in metal‐rich soils.
D e herb might absorb metals from any metal‐rich soil it grows in, regardless of why it thrives in that soil.
E Whether or not histidine concentrations in the herb decline as it approaches maturity, there could still be
enough histidine in the growing herb to neutralize the metals and explain why it can grow in metal‐rich
soil.
e correct answer is B.
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645. Many people suffer an allergic reaction to certain sul tes, including those that are commonly added to wine as
preservatives. However, since there are several winemakers who add sul tes to none of the wines they produce, people
who would like to drink wine but are allergic to sul tes can drink wines produced by these winemakers without risking an
allergic reaction to sul tes.
Which of the following is an assumption on which the argument depends?
(A) These winemakers have been able to duplicate the preservative effect produced by adding sul tes by means that do
not involve adding any potentially allergenic substances to their wine.
(B) Not all forms of sul te are equally likely to produce the allergic reaction.
(C) Wine is the only beverage to which sul tes are commonly added.
(D) Apart from sul tes, there are no substances commonly present in wine that give rise to an allergic reaction.
(E) Sul tes are not naturally present in the wines produced by these winemakers in amounts large enough to produce an
allergic reaction in someone who drinks these wines.
Argument Construction
Situation People who are allergic to certain sul tes can avoid risking an allergic reaction by drinking wine
from one of the several producers that does not add sul tes.
Reasoning On what assumption does the argument depend? Drinking wine to which no sul tes have been added
will not prevent exposure to sul tes if, for instance, sul tes occur naturally in wines. In particular,
if the wines that do not have sul tes added have sul tes present naturally in quantities su cient
to produce an allergic reaction, drinking these wines will not prevent an allergic reaction. e
argument therefore depends on assuming that this is not the case.
A e argument does not require this because the conclusion does not address allergic reactions to substances
other than sul tes.
B e argument speci cally refers to “certain sul tes” producing allergic reactions. It is entirely compatible
with certain other forms of sul tes not producing allergic reactions in anyone.
C is is irrelevant. e argument does not claim that one can avoid having an allergic reaction to sul tes
from any source just by restricting one’s wine consumption to those varieties to which no sul tes have been
added.
D Once again, the argument’s conclusion does not address allergic reactions to substances other than sul tes
in wine.
E Correct. e argument relies on this assumption.
e correct answer is E.
649
8.6 Critical Reasoning Answer Explanations
646. A new law gives ownership of patents—documents providing exclusive right to make and sell an invention—to universities,
not the government, when those patents result from government‐sponsored university research. Administrators at Logos
University plan to sell any patents they acquire to corporations in order to fund programs to improve undergraduate
teaching.
Which of the following, if true, would cast the most doubt on the viability of the college administrators’ plan described
above?
(A) Profit‐making corporations interested in developing products based on patents held by universities are likely to try to
serve as exclusive sponsors of ongoing university research projects.
(B) Corporate sponsors of research in university facilities are entitled to tax credits under new federal tax‐code guidelines.
(C) Research scientists at Logos University have few or no teaching responsibilities and participate little if at all in the
undergraduate programs in their field.
(D) Government‐sponsored research conducted at Logos University for the most part duplicates research already
completed by several profit‐making corporations.
(E) Logos University is unlikely to attract corporate sponsorship of its scientific research.
Evaluation of a Plan
Situation Universities own the patents resulting from government‐sponsored research at their institutions.
One university plans to sell its patents to corporations to fund a program to improve teaching.
Reasoning Which point casts doubt on the university’s plan? e university’s plan assumes there will be a market
for its patents, and that the corporations will want to buy them. What might make this untrue?
If some of the corporations have already done the same or similar research, they will not be
prospective buyers of the university’s patents.
A is point is irrelevant to the plan to sell patents in order to fund a program.
B e university plans to sell the patents to the corporations, not to invite the corporations to sponsor
research.
C is point is irrelevant to the university’s plan to sell o patents since the plan does not specify that the
research scientists will be involved in the programs to improve undergraduate teaching.
D Correct . is statement properly identi es a factor that casts doubt on the university’s plan to sell its
patents to corporations.
E e plan concerns selling patents resulting from government‐sponsored research, not attracting corporate
sponsorship for research.
e correct answer is D.
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GMAT® Offi cial Guide 2018
647. Since it has become known that several of a bank’s top executives have been buying shares in their own bank , the
bank’s depositors, who had been worried by rumors that the bank faced impending nancial collapse, have been greatly
relieved. They reason that, since top executives evidently have faith in the bank’s nancial soundness, those worrisome
rumors must be false. Such reasoning might well be overoptimistic, however, since corporate executives have been
known to buy shares in their own company in a calculated attempt to dispel negative rumors about the
company’s health.
In the argument given, the two boldfaced portions play which of the following roles?
(A) The rst describes evidence that has been taken as supporting a conclusion; the second gives a reason for
questioning that support.
(B) The rst describes evidence that has been taken as supporting a conclusion; the second states a contrary conclusion
that is the main conclusion of the argument.
(C) The rst provides evidence in support of the main conclusion of the argument; the second states that conclusion.
(D) The rst describes the circumstance that the argument as a whole seeks to explain; the second gives the explanation
that the argument seeks to establish.
(E) The rst describes the circumstance that the argument as a whole seeks to explain; the second provides evidence in
support of the explanation that the argument seeks to establish.
Argument Evaluation
Situation Top executives at a bank that has been rumored to be in nancial trouble have been buying shares
in the bank. Bank depositors see this as a good sign, because they believe that it indicates that the
executives have faith in the bank. However, corporate executives sometimes do this just to dispel
rumors about a company’s health.
Reasoning What is the role that the two boldfaced portions play in the argument? e rst boldfaced portion
states that bank executives are buying bank shares, which the passage indicates is taken by bank
depositors to be evidence of the executives’ faith in the bank. e passage then tells us what
some have inferred from this, and nally o ers in the second boldfaced statement evidence that
undermines this inference.
A Correct. is option correctly identi es the roles played by the boldfaced portions.
B is correctly describes the rst statement’s role, but the second statement is not o ered as a conclusion—
no evidence is given for it; rather it is evidence for something else.
C e second statement is not o ered as a conclusion; no evidence is given for it.
D e second statement is not itself o ered as an explanation of why these bank executives are investing in
the bank; if it were, that would mean that the bank executives are doing so because corporate executives
are known to do such things in a calculated e ort to dispel worries. Furthermore the argument does not
conclude that this other explanation (which the boldfaced portion points to) is correct, only that the one
inferred by depositors may not be.
E e argument is not so much seeking to establish an explanation of its own as it is trying to undermine
that inferred by the depositors.
e correct answer is A.
651
8.6 Critical Reasoning Answer Explanations
648. Between 1980 and 2000 the sea otter population of the Aleutian Islands declined precipitously. There were no signs of
disease or malnutrition, so there was probably an increase in the number of otters being eaten by predators. Orcas will eat
otters when seals, their normal prey, are unavailable, and the Aleutian Islands seal population declined dramatically in the
1980s. Therefore, orcas were most likely the immediate cause of the otter population decline.
Which of the following, if true, most strengthens the argument?
(A) The population of sea urchins, the main food of sea otters, has increased since the sea otter population declined.
(B) Seals do not eat sea otters, nor do they compete with sea otters for food.
(C) Most of the surviving sea otters live in a bay that is inaccessible to orcas.
(D) The population of orcas in the Aleutian Islands has declined since the 1980s.
(E) An increase in commercial shing near the Aleutian Islands in the 1980s caused a slight decline in the population of
the sh that seals use for food.
Argument Evaluation
Situation A sea otter population declined even though there were no signs of disease or malnutrition.
e local seal population also declined. Orcas eat otters when seals are unavailable, and thus are
probably the cause of the decline in the otter population.
Reasoning What would be evidence that predation by orcas reduced the sea otter population? Disease and
malnutrition are ruled out as alternative explanations of the decline in the sea otter population.
e argument could be further strengthened by casting doubt on other possible explanations,
such as predation by other animals, or by presenting observations that predation of otters by orcas
would help to explain.
A Regardless of whether or not orcas ate the sea otters, the sea urchin population would most likely have
increased when the population of sea otters preying on them decreased.
B Because the seal population declined during the initial years of the otter population decline, predation by
and competition with seals were already implausible explanations of the otter population decline.
C Correct. Orcas eating most of the accessible otters could plausibly explain this observation, which
therefore provides additional evidence that orca predation reduced the sea otter population.
D If the orca population declined at the same time as the sea otter population, it would be less likely that
increasing predation by orcas reduced the otter population.
E Since the sea otters showed no signs of malnutrition, they were probably getting enough sh. But if they
were not, commercial shing rather than orcas might have caused the otter population decline.
e correct answer is C.
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GMAT® Offi cial Guide 2018
649. Studies in restaurants show that the tips left by customers who pay their bill in cash tend to be larger when the bill is
presented on a tray that bears a credit‐card logo. Consumer psychologists hypothesize that simply seeing a credit‐card logo
makes many credit‐card holders willing to spend more because it reminds them that their spending power exceeds the cash
they have immediately available.
Which of the following, if true, most strongly supports the psychologists’ interpretation of the studies?
(A) The effect noted in the studies is not limited to patrons who have credit cards.
(B) Patrons who are under nancial pressure from their credit‐card obligations tend to tip less when presented with a
restaurant bill on a tray with a credit‐card logo than when the tray has no logo.
(C) In virtually all of the cases in the studies, the patrons who paid bills in cash did not possess credit cards.
(D) In general, restaurant patrons who pay their bills in cash leave larger tips than do those who pay by credit card.
(E) The percentage of restaurant bills paid with a given brand of credit card increases when that credit card’s logo is
displayed on the tray with which the bill is presented.
Argument Evaluation
Situation Studies have found that restaurant customers give more generous tips when their bills are brought
on trays bearing a credit‐card logo. Psychologists speculate that this is because the logo reminds
customers of their ability to spend more money than they have.
Reasoning Which of the options most helps to support the psychologists’ explanation of the studies? e psychologists’
hypothesis is that the credit‐card logos on the trays bring to the minds of those who tip more
the fact that they have more purchasing power than merely the cash that they have at hand. is
explanation would not be valid even if those people who are not reminded of their own excess
purchasing power—if in fact they have any such power—when they see such a logo nonetheless
tip more in such trays. us, if restaurant patrons who are under nancial pressure from their
credit‐card obligations do not tip more when their bills are presented on trays bearing credit‐card
logos, then the psychologists’ interpretation of the studies is supported.
A is undermines the psychologists’ interpretation, for it shows that the same phenomenon occurs even
when the alleged cause has been removed.
B Correct. is option identi es the result that would most strengthen the psychologists’ interpretation.
C is undermines the psychologists’ interpretation by showing that the same phenomenon occurs even
when the alleged cause has been removed; patrons cannot be reminded of something that is not there.
D To the extent that this bears on the interpretation of the study, it weakens it. Patrons using credit cards are
surely aware that they have credit, and yet they spend less generously.
E is does not support the idea that being reminded that one has a credit card induces one to be more
generous , only that it induces one to use that credit card.
e correct answer is B.
653
8.6 Critical Reasoning Answer Explanations
650. In an experiment, each volunteer was allowed to choose between an easy task and a hard task and was told that another
volunteer would do the other task. Each volunteer could also choose to have a computer assign the two tasks randomly.
Most volunteers chose the easy task for themselves and under questioning later said they had acted fairly. But when the
scenario was described to another group of volunteers, almost all said choosing the easy task would be unfair. This shows
that most people apply weaker moral standards to themselves than to others.
Which of the following is an assumption required by this argument?
(A) At least some volunteers who said they had acted fairly in choosing the easy task would have said that it was unfair
for someone else to do so.
(B) The most moral choice for the volunteers would have been to have the computer assign the two tasks randomly.
(C) There were at least some volunteers who were assigned to do the hard task and felt that the assignment was unfair.
(D) On average, the volunteers to whom the scenario was described were more accurate in their moral judgments than
the other volunteers were.
(E) At least some volunteers given the choice between assigning the tasks themselves and having the computer assign
them felt that they had made the only fair choice available to them.
Argument Construction
Situation In an experiment, most volunteers chose to do an easy task themselves and leave a hard task for
someone else. ey later said they had acted fairly, but almost all volunteers in another group to
which the scenario was described said choosing the easy task would be unfair, indicating that most
people apply weaker moral standards to themselves.
Reasoning What must be true in order for the facts presented to support the conclusion that most people apply weaker
moral standards to themselves than to others? One set of volunteers said they had acted fairly in
taking the easy task, whereas di erent volunteers said that doing so would be unfair. In neither
case did any of the volunteers actually judge their own behavior di erently from how they judged
anyone else’s. So the argument implicitly infers from the experimental results that most of the
volunteers would judge their own behavior di erently from someone else’s if given the chance.
is inference assumes that the volunteers in the second group would have applied the same moral
standards that those in the rst group did if they had been in the rst group’s position, and vice
versa.
A Correct. If none of the volunteers who said their own behavior was fair would have judged someone else’s
similar behavior as unfair, then their relaxed moral judgment of themselves would not suggest that they
applied weaker moral standards to themselves than to others.
B Even if this is so, the experimental results could still suggest that the volunteers would apply weaker moral
standards to themselves than to others.
C e argument would be equally strong even if volunteers who were assigned the hard task did not know
that someone else had gotten an easier task—or even if no volunteers were actually assigned the hard task
at all.
D Even if the moral standards applied by the volunteers who judged themselves were as accurate as those
applied by the volunteers to whom the scenario was described, the former standards were still weaker.
E Even if all the volunteers in the rst group had felt that all the choices available to them would have been
fair for them to make personally, they might have applied stricter moral standards to someone else in the
same position.
e correct answer is A.
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GMAT® Offi cial Guide 2018
651. Country X’s recent stock-trading scandal should not diminish investors’ con dence in the country’s stock market. For one
thing, the discovery of the scandal con rms that Country X has a strong regulatory system, as the following
considerations show. In any stock market, some fraudulent activity is inevitable. If a stock market is well regulated,
any signi cant stock-trading fraud in it will very likely be discovered. This deters potential perpetrators and facilitates
improvement in regulatory processes.
In the argument, the portion in boldface plays which of the following roles?
(A) It is the argument’s only conclusion.
(B) It is a conclusion for which the argument provides support and which itself is used to support the argument’s main
conclusion.
(C) It is the argument’s main conclusion and is supported by another explicitly stated conclusion for which further support
is provided.
(D) It is an assumption for which no explicit support is provided and is used to support the argument’s only conclusion.
(E) It is a compound statement containing both the argument’s main conclusion and an assumption used to support that
conclusion.
Argument Construction
Situation Country X recently had a stock-trading scandal.
Reasoning What role does the statement that the scandal’s discovery con rms that Country X has a strong regulatory
system play in the argument? In the sentence containing the boldface statement, the phrase For
one thing indicates that the statement is being used to justify the claim in the preceding sentence.
us, the boldface statement must support that preceding sentence as a conclusion. Directly after
the boldface statement, the phrase as the following considerations show indicates that the subsequent
sentences are being used to support the boldface statement. us, the boldface statement is a
conclusion supported by the sentences following it, and this statement itself supports the sentence
preceding it, which must be the argument’s main conclusion.
A As explained above, the boldface statement supports the claim in the preceding sentence, so it cannot be
the argument’s only conclusion.
B Correct. As explained above, the boldface statement is supported by the statements following it and in
turn is used to support the argument’s main conclusion in the statement preceding it.
C As explained above, the boldface statement cannot be the argument’s main conclusion, because it supports
a further conclusion presented in the sentence preceding it.
D As explained above, the sentences following the boldface statement are the explicit support provided for it.
E As explained above, the argument’s main conclusion is stated only in the rst sentence, which precedes the
boldface statement. It is not repeated anywhere in the boldface statement.
e correct answer is B.
655
8.6 Critical Reasoning Answer Explanations
652. Delta Products Inc. has recently switched at least partly from older technologies using fossil fuels to new
technologies powered by electricity. The question has been raised whether it can be concluded that for a given level
of output Delta’s operation now causes less fossil fuel to be consumed than it did formerly. The answer, clearly, is
yes, since the amount of fossil fuel used to generate the electricity needed to power the new technologies is less than the
amount needed to power the older technologies, provided level of output is held constant.
In the argument given, the two boldfaced portions play which of the following roles?
(A) The rst identi es the content of the conclusion of the argument; the second provides support for that conclusion.
(B) The rst provides support for the conclusion of the argument; the second identi es the content of that conclusion.
(C) The rst states the conclusion of the argument; the second calls that conclusion into question.
(D) The rst provides support for the conclusion of the argument; the second calls that conclusion into question.
(E) Each provides support for the conclusion of the argument.
Argument Evaluation
Situation Delta switched from technologies using fossil fuels to ones using electricity. It has been asked
whether this results in less fossil fuel used per level of output. e answer is that it does.
Reasoning What roles do the two boldfaced portions play in the argument? e rst boldfaced statement is simply
asserted by the passage. But the second boldfaced statement, when it is rst introduced, is not
asserted to be true, but rather is identi ed as something that might be inferred from the rst
statement. By the end of the passage the argument concludes that the second statement is true.
A is option simply reverses the roles that the statements play in the argument.
B Correct. is option identi es the roles the boldfaced portions play.
C Nothing in the passage is intended to support the rst statement; and the second statement is not
supposed to call the rst into question.
D is correctly identi es the role of the rst statement, but the second boldfaced portion does not call the
argument’s conclusion into question—it is part of a sentence that refers to the question whether that
conclusion can be drawn from the rst statement.
E Again, this is only half right. e second boldfaced portion is not o ered as support for the conclusion;
if it were o ered as such support, the argument would be guilty of circular reasoning, since the second
boldfaced portion states exactly what the argument concludes.
e correct answer is B.
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GMAT® Offi cial Guide 2018
653. Theater Critic: The play La Finestrina , now at Central Theater, was written in Italy in the eighteenth century. The director
claims that this production is as similar to the original production as is possible in a modern theater. Although the actor who
plays Harlequin the clown gives a performance very reminiscent of the twentieth‐century American comedian Groucho Marx,
Marx’s comic style was very much within the comic acting tradition that had begun in sixteenth‐century Italy.
The considerations given best serve as part of an argument that
(A) modern audiences would nd it hard to tolerate certain characteristics of a historically accurate performance of an
eighteenth‐century play
(B) Groucho Marx once performed the part of the character Harlequin in La Finestrina
(C) in the United States the training of actors in the twentieth century is based on principles that do not differ radically
from those that underlay the training of actors in eighteenth‐century Italy
(D) the performance of the actor who plays Harlequin in La Finestrina does not serve as evidence against the director’s
claim
(E) the director of La Finestrina must have advised the actor who plays Harlequin to model his performance on comic
performances of Groucho Marx
Argument Construction
Situation e director of the local production of La Finestrina says it is as similar to the original production
as is possible in a modern theater. e actor playing Harlequin gives a performance reminiscent
of Groucho Marx, whose comic style falls within an acting tradition which began in sixteenth‐
century Italy.
Reasoning For which of the options would the consideration given best serve as an argument? e actor’s
performance was reminiscent of someone who fell within a tradition going back to sixteenth‐
century Italy. e play was written, and therefore was likely rst performed, in eighteenth‐century
Italy. All of this suggests that there could be a similarity between the performances of Harlequin
in the local production and in the original production. While the two performances might have
been quite dissimilar, there is nothing here that supports that.
A Regardless of how plausible this option might be on its own merits, the passage provides no support
for it because the passage provides no information about the characteristics of a historically accurate
performance of an eighteenth‐century play.
B e passage neither says this nor implies it.
C e passage says nothing about the training of actors, so this option would be supported by the passage
only in a very roundabout, indirect way.
D Correct. is is the option that the considerations most support.
E at the performance reminded the theater critic of Groucho Marx hardly shows that the similarity was
intentional, let alone that it was at the director’s instruction.
e correct answer is D.
657
8.6 Critical Reasoning Answer Explanations
654. Although the discount stores in Goreville’s central shopping district are expected to close within ve years as a result of
competition from a SpendLess discount department store that just opened, those locations will not stay vacant for long.
In the ve years since the opening of Colson’s, a nondiscount department store, a new store has opened at the location of
every store in the shopping district that closed because it could not compete with Colson’s.
Which of the following, if true, most seriously weakens the argument?
(A) Many customers of Colson’s are expected to do less shopping there than they did before the SpendLess store
opened.
(B) Increasingly, the stores that have opened in the central shopping district since Colson’s opened have been discount
stores.
(C) At present, the central shopping district has as many stores operating in it as it ever had.
(D) Over the course of the next ve years, it is expected that Goreville’s population will grow at a faster rate than it has
for the past several decades.
(E) Many stores in the central shopping district sell types of merchandise that are not available at either SpendLess or
Colson’s.
Argument Evaluation
Situation Due to competition from a recently opened SpendLess discount department store, discount stores
in Goreville’s central shopping district are expected to close within ve years. But those locations
will not be vacant long, for new stores have replaced all those that closed because of the opening
ve years ago of a Colson’s nondiscount department store.
Reasoning e question is which option would most weaken the argument? e arguer infers that stores that leave
because of the SpendLess will be replaced in their locations by other stores because that is what
happened after the Colson’s department store came in. Since the reasoning relies on a presumed
similarity between the two cases, any information that brings to light a relevant dissimilarity
would weaken the argument. If the stores that were driven out by Colson’s were replaced mostly by
discount stores, that suggests that the stores were replaced because of a need that no longer exists
after the opening of SpendLess.
A e fact that Colson’s may be seeing fewer customers does not mean that the discount stores that close will
not be replaced; they might be replaced by stores that in no way compete with Colson’s or SpendLess.
B Correct. is option most seriously weakens the argument.
C If anything, this strengthens the argument by indicating that Goreville’s central shopping district is
thriving.
D is, too, strengthens the argument because one is more likely to open a new store in an area with a
growing population.
E Because this statement does not indicate whether any of these stores that o er goods not sold at
SpendLess or Colson’s will be among those that are closing, it is not possible to determine what e ect it
has on the strength of the argument.
e correct answer is B.
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GMAT® Offi cial Guide 2018
655. Last year all refuse collected by Shelbyville city services was incinerated. This incineration generated a large quantity of
residual ash. In order to reduce the amount of residual ash Shelbyville generates this year to half of last year’s total, the city
has revamped its collection program. This year city services will separate for recycling enough refuse to reduce the number
of truckloads of refuse to be incinerated to half of last year’s number.
Which of the following is required for the revamped collection program to achieve its aim?
(A) This year, no materials that city services could separate for recycling will be incinerated.
(B) Separating recyclable materials from materials to be incinerated will cost Shelbyville less than half what it cost last
year to dispose of the residual ash.
(C) Refuse collected by city services will contain a larger proportion of recyclable materials this year than it did last year.
(D) The refuse incinerated this year will generate no more residual ash per truckload incinerated than did the refuse
incinerated last year.
(E) The total quantity of refuse collected by Shelbyville city services this year will be no greater than that collected last
year.
Argument Construction
Situation To cut in half the residual ash produced at its incinerator, the city will separate for recycling
enough refuse to cut in half the number of truckloads of refuse going to the incinerator.
Reasoning Which option is required if the city’s revamped collection program is to achieve its aim? Cutting the
number of truckloads of refuse in half must reduce the amount of residual ash to half last year’s
level. But if removal of the recycled refuse does not proportionately reduce the amount of ash,
this will not happen. So if the amount of residual ash produced per truckload increases after
recycling, then the amount of ash produced will not be cut in half by cutting in half the number of
truckloads.
A is merely indicates that no further reduction of ash through recycling could be achieved this year; it
indicates nothing about how much the ash will be reduced.
B is suggests a further bene t from recycling, but does not bear on the amount of ash that will be
produced.
C Since no information is provided about how much, if any, recyclable materials were removed from the
refuse last year, this does not a ect the reasoning.
D Correct. is states a requirement for the collection program to achieve its aim.
E is is not a requirement because even if the city collects more refuse this year, it could still cut in half the
amount of residual ash by cutting in half the number of truckloads going to the incinerator.
e correct answer is D.
659
8.6 Critical Reasoning Answer Explanations
656. Veterinarians generally derive some of their income from selling several manufacturers’ lines of pet-care products. Knowing
that pet owners rarely throw away mail from their pet’s veterinarian unread, one manufacturer of pet-care products offered
free promotional materials on its products to veterinarians for mailing to their clients. Very few veterinarians accepted the
offer, however, even though the manufacturer’s products are of high quality.
Which of the following, if true, most helps to explain the veterinarians’ reaction to the manufacturer’s promotional scheme?
(A) Most of the veterinarians to whom the free promotional materials were offered were already selling the manufacturer’s
pet-care products to their clients.
(B) The special promotional materials were intended as a supplement to the manufacturer’s usual promotional activities
rather than as a replacement for them.
(C) The manufacturer’s products, unlike most equally good competing products sold by veterinarians, are also available in
pet stores and in supermarkets.
(D) Many pet owners have begun demanding quality in products they buy for their pets that is as high as that in products
they buy for themselves.
(E) Veterinarians sometimes recommend that pet owners use products formulated for people when no suitable product
specially formulated for animals is available.
Evaluation of a Plan
Situation Veterinarians generally derive some income from selling various manufacturers’ pet-care products,
but very few veterinarians accepted free promotional materials from one such manufacturer to mail
to their clients.
Reasoning What would most help explain why so few veterinarians accepted the free promotional materials to mail
to their clients? e passage says that veterinarians generally derive income from selling pet-care
products, which suggests that it should have been in many veterinarians’ nancial interest to accept
and mail out the free promotional materials to increase sales. Any evidence that mailing out these
speci c promotional materials from this manufacturer would not actually have been in many
veterinarians’ nancial interest could help explain why so few veterinarians accepted the materials.
A is suggests that most of the veterinarians should have had a nancial interest in accepting and mailing
out the promotional materials in order to increase their sales of the manufacturer’s products.
B Even if the promotional materials supplemented the manufacturer’s usual promotional activities, they
could still have increased the veterinarians’ sales of the manufacturer’s products and thus generated more
income for the veterinarians.
C Correct. If this manufacturer’s products are available in pet stores and supermarkets but most other
products sold by veterinarians are not, then distributing the manufacturer’s promotional materials could
have encouraged customers to buy this manufacturer’s products from pet stores and supermarkets rather
than to buy competing products from the veterinarians. us, the veterinarians may have been concerned
that the promotions would reduce their pro ts.
D e passage says the manufacturer’s products are of high quality, so we have no reason to suppose that
clients’ demand for quality products would discourage veterinarians from accepting the manufacturer’s
promotional materials.
E Presumably the manufacturer’s products are specially formulated for pets, so any products veterinarians
recommend only when no specially formulated pet-care products are available would not reduce the
veterinarians’ interest in promoting the manufacturer’s products.
e correct answer is C.
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GMAT® Offi cial Guide 2018
657. The average hourly wage of television assemblers in Vernland has long been signi cantly lower than that in neighboring
Borodia. Since Borodia dropped all tariffs on Vernlandian televisions three years ago, the number of televisions sold annually
in Borodia has not changed. However, recent statistics show a drop in the number of television assemblers in Borodia.
Therefore, updated trade statistics will probably indicate that the number of televisions Borodia imports annually from
Vernland has increased.
Which of the following is an assumption on which the argument depends?
(A) The number of television assemblers in Vernland has increased by at least as much as the number of television
assemblers in Borodia has decreased.
(B) Televisions assembled in Vernland have features that televisions assembled in Borodia do not have.
(C) The average number of hours it takes a Borodian television assembler to assemble a television has not decreased
signi cantly during the past three years.
(D) The number of televisions assembled annually in Vernland has increased signi cantly during the past three years.
(E) The difference between the hourly wage of television assemblers in Vernland and the hourly wage of television
assemblers in Borodia is likely to decrease in the next few years.
Argument Construction
Situation Television assemblers in Vernland are paid less than those in neighboring Borodia. e number
of televisions sold in Borodia has not dropped since its tari s on Vernlandian TVs were lowered
three years ago, but the number of TV assemblers in Borodia has. So TV imports from Vernland
have likely increased.
Reasoning What assumption does the argument depend on? e fact that fewer individuals in Borodia are
working as TV assemblers is o ered as evidence that TV imports from Vernland into Borodia
have likely increased. at piece of evidence is relevant only as an indication that the number of
TVs being produced within Borodia has decreased. But a drop in the number of TV assemblers
does not indicate a drop in the number of TVs being assembled if the number of TVs an average
assembler puts together has increased. us, the argument must be assuming that the average time
it takes an assembler to put together a TV has not signi cantly decreased.
A e argument does not rely on any information about the number of television assemblers in Vernland nor
for that matter on the number of TVs assembled in Vernland.
B e argument need not assume there is any di erence in the features of the TVs produced in the two
countries. Increased sales of Vernlandian TVs in Borodia could be due to any number of other reasons,
such as price or quality.
C Correct. is option states an assumption on which the argument depends.
D e argument does not depend upon this being so: Vernland’s domestic TV sales (or perhaps its exports to
countries other than Borodia) may have decreased by more than its imports into Borodia have increased.
E e argument’s conclusion addresses what has happened; the argument in no way relies on any
assumptions about what may or may not happen in the coming years.
e correct answer is C.
661
8.6 Critical Reasoning Answer Explanations
658. Guidebook writer: I have visited hotels throughout the country and have noticed that in those built before 1930 the quality of
the original carpentry work is generally superior to that in hotels built afterward. Clearly carpenters working on hotels before
1930 typically worked with more skill, care, and effort than carpenters who have worked on hotels built subsequently.
Which of the following, if true, most seriously weakens the guidebook writer’s argument?
(A) The quality of original carpentry in hotels is generally far superior to the quality of original carpentry in other
structures, such as houses and stores.
(B) Hotels built since 1930 can generally accommodate more guests than those built before 1930.
(C) The materials available to carpenters working before 1930 were not signi cantly different in quality from the materials
available to carpenters working after 1930.
(D) The better the quality of original carpentry in a building, the less likely that building is to fall into disuse and be
demolished.
(E) The average length of apprenticeship for carpenters has declined signi cantly since 1930.
Argument Evaluation
Situation e original carpentry in hotels built before 1930 shows superior care, skill, and e ort to that in
hotels built after 1930. is leads to the conclusion that carpenters working on hotels before 1930
were superior in skill, care, and e ort to those that came after.
Reasoning Which option most seriously weakens the argument? e argument draws an inference from a
comparison between carpentry in hotels of di erent eras to a judgment about the carpenters
working on hotels in those eras. One way to weaken this inference is by nding some way in
which the carpentry in the hotels may be unrepresentative of the skill, care, and e ort of the
carpenters working in the eras. e comparison is between the carpentry evident in hotels of
the two eras that still exist . us, if there is some reason to think that hotels with good carpentry
survive longer than those with bad carpentry, then still‐existing hotels from the older era will have
disproportionately more good carpentry, even assuming no di erence between the skill, care, and
e ort of the carpenters from the two eras.
A is option applies equally to both eras, so it has no bearing on the argument.
B It is not clear whether carpenters working on larger hotels would exercise more, less, or the same skill and
care as those working on smaller hotels; thus this option does not weaken the argument.
C e argument does not rely, even implicitly, on there being any di erence in the quality of materials used
in the two eras, so it does not weaken the argument to point out that no such di erence exists.
D Correct. is weakens the reasoning in the argument by showing a respect in which the comparison
between existing hotels is unrepresentative.
E e longer a carpenter works as an apprentice, the more skill he or she is apt to have upon becoming a
full‐ edged carpenter. So this option would tend to slightly strengthen rather than weaken the argument.
e correct answer is D.
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659. Scientists typically do their most creative work before the age of forty. It is commonly thought that this happens because
aging by itself brings about a loss of creative capacity. However, studies show that of scientists who produce highly
creative work beyond the age of forty, a disproportionately large number entered their eld at an older age
than is usual. Since by the age of forty the large majority of scientists have been working in their eld for at least fteen
years, the studies’ nding strongly suggests that the real reason why scientists over forty rarely produce highly creative
work is not that they have aged but rather that scientists over forty have generally spent too long in their eld.
In the argument given, the two portions in boldface play which of the following roles?
(A) The rst is a claim, the accuracy of which is at issue in the argument; the second is a conclusion drawn on the basis
of that claim.
(B) The rst is an objection that has been raised against a position defended in the argument; the second is that position.
(C) The rst is evidence that has been used to support an explanation that the argument challenges; the second is that
explanation.
(D) The rst is evidence that has been used to support an explanation that the argument challenges; the second is a
competing explanation that the argument favors.
(E) The rst provides evidence to support an explanation that the argument favors; the second is that explanation.
Argument Evaluation
Situation It is generally thought that the reason scientists tend to do their most creative work before age
forty is that creative capacity declines with age. Yet those scientists who do creative work after
forty tend, disproportionately, to have started their careers in science later in life. So a better
explanation is that many scientists over forty have just been at it too long.
Reasoning What roles do the two portions of the argument that are in boldface play? e argument describes a
phenomenon and what is commonly thought to explain it. en, the rst boldfaced statement
introduces evidence that suggests that there may be another explanation. After this evidence is
further developed, the argument then concludes that there is indeed a better explanation for the
phenomenon; that explanation is stated in the second boldfaced portion.
A e accuracy of the rst statement is never called into question by the argument; rather, it is relied upon as
the basis for the argument’s conclusion.
B e rst statement is not an objection against the position the argument defends; instead, it is a basis for
that position.
C e rst statement is not used to support a position the argument challenges, and the second statement is
the explanation the argument supports, not the one it challenges.
D e second statement is indeed an explanation that the argument favors; but the rst statement is not used
to support a competing explanation that the argument challenges.
E Correct. is option correctly identi es the roles played by the boldfaced portions of the argument.
e correct answer is E.
663
8.6 Critical Reasoning Answer Explanations
660. NorthAir charges low fares for its economy-class seats, but it provides very cramped seating and few amenities. Market
research shows that economy passengers would willingly pay more for wider seating and better service, and additional
revenue provided by these higher ticket prices would more than cover the additional cost of providing these amenities. Even
though NorthAir is searching for ways to improve its pro tability, it has decided not to make these improvements.
Which of the following, if true, would most help to explain NorthAir’s decision in light of its objectives?
(A) None of NorthAir’s competitors offers signi cantly better seating and service to economy-class passengers than
NorthAir does.
(B) On many of the routes that NorthAir ies, it is the only airline to offer direct ights.
(C) A few of NorthAir’s economy-class passengers are satis ed with the service they receive, given the low price they
pay.
(D) Very few people avoid ying on NorthAir because of the cramped seating and poor service offered in economy class.
(E) The number of people who would be willing to pay the high fares NorthAir charges for its business-class seats would
decrease if its economy-class seating were more acceptable.
Evaluation of a Plan
Situation Market research shows that improving some amenities for economy-class passengers would allow
NorthAir to raise its economy ticket prices more than enough to cover the additional cost of
providing those amenities. But NorthAir has decided not to improve those amenities, even though
it is looking for ways to improve its pro tability.
Reasoning What would most help explain why NorthAir decided not to improve the seating and other amenities,
even though the resulting increase in economy-class ticket prices would more than cover the expense?
NorthAir is looking for ways to improve its pro tability. Making improvements that would
increase ticket prices enough to generate more revenue than they cost should improve pro tability,
other things being equal. But if improving the amenities would generate side e ects that reduced
pro tability, those side e ects would provide a good reason for NorthAir’s decision not to improve
the amenities and hence would help explain why NorthAir made that decision.
A e passage says that for NorthAir, the cost of providing better economy seating and other amenities
would be more than met by the increased revenue from the higher ticket prices that passengers would be
willing to pay. is could give NorthAir a competitive edge, with improved pro tability.
B Even if NorthAir faces little or no competition on certain routes, o ering extra amenities might increase
passengers’ interest in ying those routes. It might also lead passengers to choose NorthAir on other routes
that competing airlines also serve. Both of these e ects could improve NorthAir’s pro tability.
C Even if a few NorthAir economy passengers would not pay more for extra amenities, the market research
indicates that most of them would, so o ering the amenities could still improve NorthAir’s pro ts
attributable to economy-class seating.
D is suggests that improving the amenities would not increase the total number of NorthAir passengers.
But improving the amenities might still enable the airline to increase its ticket prices per passenger enough
to improve its pro tability.
E Correct. is suggests that improving the economy-class amenities would reduce NorthAir’s revenue
from sales of business-class tickets, which are likely much more expensive than economy-class tickets. is
reduction in revenue could be enough to reduce NorthAir’s total pro tability despite the increased revenue
from economy-class ticket sales.
e correct answer is E.
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661. Which of the following most logically completes the argument given?
Asthma, a chronic breathing disorder, is signi cantly more common today among adult competitive swimmers than it
is among competitive athletes who specialize in other sports. Although chlorine is now known to be a lung irritant and
swimming pool water is generally chlorinated, it would be rash to assume that frequent exposure to chlorine is the
explanation of the high incidence of asthma among these swimmers, since __________.
(A) young people who have asthma are no more likely to become competitive athletes than are young people who do not
have asthma
(B) competitive athletes who specialize in sports other than swimming are rarely exposed to chlorine
(C) competitive athletes as a group have a signi cantly lower incidence of asthma than do people who do not participate
in competitive athletics
(D) until a few years ago, physicians routinely recommended competitive swimming to children with asthma, in the belief
that this form of exercise could alleviate asthma symptoms
(E) many people have asthma without knowing they have it and thus are not diagnosed with the condition until they begin
engaging in very strenuous activities, such as competitive athletics
Argument Construction
Situation Asthma is more common among competitive swimmers than among other competitive athletes.
Chlorine is a lung irritant generally present in swimming pool water.
Reasoning What would cast doubt on the hypothesis that exposure to chlorine in swimming pools accounts for the
high incidence of asthma among adult competitive swimmers? Evidence of any other factor that would
provide an alternative explanation of why asthma is more common among adult competitive
swimmers than among other competitive athletes would make it rash to assume that frequent
exposure to chlorine explains the high incidence of asthma among these swimmers, so a statement
providing such evidence would logically ll in the blank at the end of the passage to complete the
argument.
A is might help explain why competitive athletes in general are not especially likely to have asthma, but it
does not explain why adult competitive swimmers are more likely to have asthma than other competitive
athletes are.
B is provides additional evidence that exposure to chlorine explains why adult competitive swimmers
are more likely to have asthma than other competitive athletes are, so it does not cast doubt on that
hypothesis.
C A lower incidence of asthma among competitive athletes than among nonathletes does not help explain
the higher incidence of asthma among adult competitive swimmers than among other competitive athletes.
D Correct. Routinely encouraging children with asthma to take up competitive swimming would likely
have made the proportion of adult competitive swimmers with asthma exceed the proportion of other
competitive athletes with asthma, even if chlorine in swimming pool water never causes asthma in
swimmers.
E is might help explain why people with asthma are just as likely as other people to become competitive
athletes, but it does not help explain why adult competitive swimmers are more likely to have asthma than
other competitive athletes are.
e correct answer is D.
665
8.6 Critical Reasoning Answer Explanations
662. In the country of Marut, the Foreign Trade Agency’s records were reviewed in 1994 in light of information then newly
available about neighboring Goro. The review revealed that in every year since 1963, the agency’s projection of what Goro’s
gross national product (GNP) would be ve years later was a serious underestimate. The review also revealed that in every
year since 1963, the agency estimated Goro’s GNP for the previous year—a Goro state secret—very accurately.
Of the following claims, which is most strongly supported by the statements given?
(A) Goro’s GNP uctuated greatly between 1963 and 1994.
(B) Prior to 1995, Goro had not released data intended to mislead the agency in making its ve‐year projections.
(C) The amount by which the agency underestimated the GNP it projected for Goro tended to increase over time.
(D) Even before the new information came to light, the agency had reason to think that at least some of the ve‐year
projections it had made were inaccurate.
(E) The agency’s ve‐year projections of Goro’s GNP had no impact on economic planning in Marut.
Argument Construction
Situation A review in 1994 revealed that every year since 1963, Marut’s Foreign Trade Agency had seriously
underestimated what Goro’s GNP would be ve years later, but accurately estimated what Goro’s
GNP had been the previous year.
Reasoning What conclusion do the stated facts most strongly support? Goro’s GNP in each year at least from 1969
through 1993 had been seriously underestimated by the agency ve years in advance, yet was then
accurately estimated by the agency one year after the fact. It follows that for each of these years,
the agency’s earlier projection of Goro’s GNP must have been much lower than its later estimate.
A is is not supported by the information given. e fact that the agency consistently underestimated each
year’s GNP in its ve‐year projections and then correctly estimated it after the fact does not indicate that
Goro’s GNP uctuated greatly.
B is is not supported by the information given. e reason the agency’s ve‐year projections were
inaccurate might well have been that Goro deliberately released data intended to mislead the agency in
making those projections.
C is is not supported by the information given. e fact that the underestimates remained large
throughout the years in question does not indicate that the underestimates increased over time.
D Correct. As explained above, for many years there were serious discrepancies between the agency’s
ve‐year projections of Goro’s GNP and its retrospective estimates of each previous year’s trade. In any
year at least from 1970 through 1993, these discrepancies, if noticed, would have given the agency reason
to doubt some of the ve‐year projections.
E is is not supported by the information given. Even though at least some of the ve‐year projections were
eventually known to be serious underestimates, they could still have a ected Marut’s economic planning.
e economic planners might have retained an unreasonable faith in the accuracy of the most recent
projections.
e correct answer is D.
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663. Vargonia has just introduced a legal requirement that student‐teacher ratios in government‐funded schools not exceed a
certain limit. All Vargonian children are entitled to education, free of charge, in these schools. When a recession occurs and
average incomes fall, the number of children enrolled in government‐funded schools tends to increase. Therefore, though
most employment opportunities contract in economic recessions, getting a teaching job in Vargonia’s government‐funded
schools will not be made more dif cult by a recession.
Which of the following would be most important to determine in order to evaluate the argument?
(A) Whether in Vargonia there are any schools not funded by the government that offer children an education free of
charge
(B) Whether the number of quali ed applicants for teaching positions in government‐funded schools increases signi cantly
during economic recessions
(C) What the current student‐teacher ratio in Vargonia’s government‐funded schools is
(D) What proportion of Vargonia’s workers currently hold jobs as teachers in government‐funded schools
(E) Whether in the past a number of government‐funded schools in Vargonia have had student‐teacher ratios well in
excess of the new limit
Argument Evaluation
Situation During a recession, the number of children in government‐funded schools in Vargonia tends to
increase. Vargonian children are entitled to a free education in these schools. A new law requires
student‐teacher ratios in these schools to remain below a certain limit.
Reasoning Which of the ve questions would provide us with the best information for evaluating the argument?
e argument’s conclusion is that recessions do not make teaching jobs in Vargonia’s
government‐funded schools harder to get. During recessions, the reasoning goes, more students
will enroll in Vargonia’s government‐funded schools than in nonrecession times. Implicit in the
argument is the thought that, because the new law sets an upper limit on the average number of
students per teacher, schools that get an in ux of new students would have to hire more teachers.
During a recession, however, there might be much more competition in the labor market for
teachers because many more quali ed people are applying for teaching jobs.
A is information is not signi cant in the context of the argument, which does not need to assume that
only government‐funded schools provide free education.
B Correct. Getting an answer to this question would provide us with speci c information useful in
evaluating the argument. A “yes” answer to this question would suggest that competition for teaching jobs
in Vargonian government‐funded schools would be keener during recessions. A “no” answer would suggest
that the level of competition would decrease during recessions.
C Discovering the current student‐teacher ratio in Vargonia’s schools would be of no value, by itself, in
evaluating the argument. We do not know what the new upper limit on the student‐teacher ratio is, and
we do not know whether Vargonia is currently in a recession.
D Finding out whether the proportion this refers to is 1 percent, for example, or 4 percent, would tell us
nothing about whether getting teaching jobs at government‐funded schools in Vargonia becomes more
di cult during a recession. Among other things, we do not know whether Vargonia is currently in a
recession, and we do not know what proportion of Vargonia’s workers would be quali ed candidates for
teaching jobs.
E is is of no relevance in evaluating the argument because, presumably, the new limit on student-teacher
ratios will be complied with. us, even if student‐teacher ratios in the past would have exceeded the new
limit, the argument concerns whether, in the future , getting a teaching job in Vargonia’s government‐funded
schools will be made more di cult by a recession.
e correct answer is B.
667
8.6 Critical Reasoning Answer Explanations
664. In Colorado subalpine meadows, nonnative dandelions co‐occur with a native ower, the larkspur. Bumblebees visit both
species, creating the potential for interactions between the two species with respect to pollination. In a recent study,
researchers selected 16 plots containing both species; all dandelions were removed from eight plots; the remaining eight
control plots were left undisturbed. The control plots yielded signi cantly more larkspur seeds than the dandelion‐free plots,
leading the researchers to conclude that the presence of dandelions facilitates pollination (and hence seed production) in
the native species by attracting more pollinators to the mixed plots.
Which of the following, if true, most seriously undermines the researchers’ reasoning?
(A) Bumblebees preferentially visit dandelions over larkspurs in mixed plots.
(B) In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.
(C) If left unchecked, nonnative species like dandelions quickly crowd out native species.
(D) Seed germination is a more reliable measure of a species’ tness than seed production.
(E) Soil disturbances can result in fewer blooms, and hence lower seed production.
Argument Evaluation
Situation Bumblebees visit both larkspur and dandelions in certain meadows. A study found that more
larkspur seeds were produced in meadow plots in which both larkspur and dandelions grew
than in similar plots from which all dandelions had been removed. e researchers inferred that
dandelions facilitate larkspur pollination.
Reasoning What evidence would cast the most doubt on the inference from the study’s ndings to the conclusion that
dandelions facilitate larkspur pollination by attracting more pollinators? e argument assumes that
the only relevant di erence between the two types of plots was whether dandelions were present.
Evidence that the plots di ered in some other way that could provide a plausible alternative
explanation of why more larkspur seeds were produced in the plots with dandelions would weaken
the argument.
A is would suggest that the larkspur pollination should have been lower in the plots with dandelions, so it
does not provide a plausible alternative explanation for the study’s ndings.
B is is fully compatible with the claim that the dandelions attracted more pollinators to the mixed plots,
and it would also help to support the argument’s conclusion that dandelions facilitated larkspur pollination
in those plots.
C Although this suggests that the mixed plots won’t remain mixed for long, it does not provide a plausible
alternative explanation for the study’s nding that larkspur seed production was higher in the mixed plots.
D e argument is not about how t larkspurs are as a species, but about why they produced di erent
numbers of seeds in the di erent plots.
E Correct. is provides a plausible alternative explanation for why larkspur seed production was lower in
the plots from which dandelions had been removed, since digging them out would have disturbed the soil.
e correct answer is E.
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665. An experiment was done in which human subjects recognize a pattern within a matrix of abstract designs and then select
another design that completes that pattern. The results of the experiment were surprising. The lowest expenditure of energy
in neurons in the brain was found in those subjects who performed most successfully in the experiments.
Which of the following hypotheses best accounts for the findings of the experiment?
(A) The neurons of the brain react less when a subject is trying to recognize patterns than when the subject is doing other
kinds of reasoning.
(B) Those who performed best in the experiment experienced more satisfaction when working with abstract patterns than
did those who performed less well.
(C) People who are better at abstract pattern recognition have more energy‐efficient neural connections.
(D) The energy expenditure of the subjects’ brains increases when a design that completes the initially recognized pattern
is determined.
(E) The task of completing a given design is more capably performed by athletes, whose energy expenditure is lower
when they are at rest.
Argument Construction
Situation Experimental subjects worked with pattern recognition and completion. e subjects who
performed best showed the lowest expenditure of energy in neurons in the brain.
Reasoning Which hypothesis best accounts for the ndings? In order to account for the ndings, the hypothesis
must suggest a plausible link between successful performance and the energy expenditure of
neurons in the brain. Consider each answer choice, and evaluate its plausibility and logic. Where is
there a reasonably direct relationship between the given factors and the conclusion that is drawn?
Understand that hypotheses based on factors not included in the experiment cannot be used to
account for the ndings.
A e experiment did not compare types of reasoning so this hypothesis does not account for the results.
B No information is provided about subjects’ satisfaction, so this hypothesis is not warranted.
C Correct. is statement properly identi es a hypothesis that connects subjects’ performance with their
energy expenditure and so could account for the experiment’s results.
D e most successful subjects would presumably not have completed fewer patterns than average, so the
posited increase in energy would likely lead to higher energy expenditures for them, not lower.
E No information is o ered on the subjects, so no hypothesis about athletes is warranted.
e correct answer is C.
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8.6 Critical Reasoning Answer Explanations
666. With seventeen casinos, Moneyland operates the most casinos in a certain state. Although intent on expanding, it was
outmaneuvered by Apex Casinos in negotiations to acquire the Eldorado chain. To complete its acquisition of Eldorado,
Apex must sell ve casinos to comply with a state law forbidding any owner to operate more than one casino per county.
Since Apex will still be left operating twenty casinos in the state, it will then have the most casinos in the state.
Which of the following, if true, most seriously undermines the prediction?
(A) Apex, Eldorado, and Moneyland are the only organizations licensed to operate casinos in the state.
(B) The majority of Eldorado’s casinos in the state will need extensive renovations if they are to continue to operate
pro tably.
(C) Some of the state’s counties do not permit casinos.
(D) Moneyland already operates casinos in the majority of the state’s counties.
(E) Apex will use funds it obtains from the sale of the ve casinos to help fund its acquisition of the Eldorado chain.
Argument Evaluation
Situation Moneyland operates seventeen casinos, the most in a certain state, and is intent on expanding.
Another operator, Apex Casinos, is acquiring the Eldorado casino chain, but must sell ve casinos
to comply with a state law forbidding any owner to operate more than one casino per county.
After these transactions, Apex will operate twenty casinos in the state.
Reasoning What observation would cast the most doubt on the prediction that Apex will have the most casinos in
the state after the transactions? Apex will operate twenty casinos, whereas Moneyland now operates
just seventeen, and no one else operates even that many. It follows that Apex will operate more
casinos after its transactions than Moneyland or any other one owner now operates. However, if
Moneyland also acquires three or more casinos during the transactions, then Apex will not have
the most casinos in the state afterward. us, any observation suggesting that Moneyland is about
to acquire several casinos would undermine the prediction.
A Correct. Since Apex is acquiring Eldorado, Moneyland and Apex will be the only remaining licensed
casino operators in the state. erefore, Moneyland is the only likely buyer for the ve casinos Apex needs
to sell. So Moneyland is likely to acquire the ve casinos during the sale and end up with twenty‐two
casinos—more than Apex.
B is does not undermine the prediction. Even if the Eldorado casinos cannot operate pro tably for long
without extensive renovations, Apex will still have twenty casinos immediately after its transactions.
C is supports rather than undermines the prediction. If fewer counties permit casinos, there will be fewer
opportunities for Moneyland or any other operator to acquire more casinos to surpass the twenty Apex
will own.
D is supports rather than undermines the prediction. If Moneyland’s seventeen casinos are in most of the
state’s counties already, then there are fewer counties in which Moneyland could acquire additional casinos
to surpass the twenty Apex will own.
E is supports rather than undermines the prediction. Apex’s use of the funds from selling the ve casinos
to acquire the Eldorado chain will not help anyone else to acquire more casinos to surpass the twenty Apex
will own.
e correct answer is A.
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667. It is widely assumed that people need to engage in intellectual activities such as solving crossword puzzles or mathematics
problems in order to maintain mental sharpness as they age. In fact, however, simply talking to other people—that is,
participating in social interaction, which engages many mental and perceptual skills—suf ces. Evidence to this effect
comes from a study showing that the more social contact people report, the better their mental skills.
Which of the following, if true, most seriously weakens the force of the evidence cited?
(A) As people grow older, they are often advised to keep exercising their physical and mental capacities in order to
maintain or improve them.
(B) Many medical conditions and treatments that adversely affect a person’s mental sharpness also tend to increase that
person’s social isolation.
(C) Many people are pro cient both in social interactions and in solving mathematical problems.
(D) The study did not itself collect data but analyzed data bearing on the issue from prior studies.
(E) The tasks evaluating mental sharpness for which data were compiled by the study were more akin to mathematics
problems than to conversation.
Argument Evaluation
Situation A study shows that the more social contact people report, the better their mental skills are, so
engaging in social interaction is su cient for maintaining mental sharpness.
Reasoning What would suggest that the study does not establish the truth of the conclusion? e study shows
a correlation between mental sharpness and social interaction but does not indicate why this
correlation exists. Evidence that mental sharpness contributes to social interaction or that some
third factor a ects both mental sharpness and social interaction, could provide an alternative
explanation for the correlation and thus cast doubt on the explanation that social interaction
contributes to mental sharpness.
A People are often wrongly advised to do things that are not actually bene cial. And even if exercising
mental capacities does help to maintain them, the passage says that social interaction provides such
exercise.
B Correct. is provides evidence that the correlation observed in the study results from mental sharpness
facilitating social interaction, in which case the study results do not indicate that social interaction
facilitates mental sharpness.
C is would be expected, given the argument’s conclusion that social interaction helps to maintain better
mental skills overall.
D A study that analyzes data from prior studies can provide evidence just as well as a study that collects its
own data can.
E e argument’s conclusion would be compatible with this observation, and would then suggest that social
interaction contributes to the mental sharpness needed for tasks similar to math problems.
e correct answer is B.
672
9.0 Sentence Correction
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9.0 Sentence Correction
9.0 Sentence Correction
Sentence correction questions appear in the Verbal section of the GMAT
® exam. e Verbal section
uses multiple‐choice questions to measure your ability to read and comprehend written material, to
reason and evaluate arguments, and to correct written material to express ideas e ectively in standard
written English. Because the Verbal section includes passages from several di erent content areas, you
may be generally familiar with some of the material; however, neither the passages nor the questions
assume detailed knowledge of the topics discussed. Sentence correction questions are intermingled with
critical reasoning and reading comprehension questions throughout the Verbal section of the test. You
will have 75 minutes to complete the Verbal section or about 1¾ minutes to answer each question.
Sentence correction questions present a statement in which words are underlined. e questions
ask you to select the best expression of the idea or relationship described in the underlined section
from the answer options. e first answer choice always repeats the original phrasing, whereas the
other four provide alternatives. In some cases, the original phrasing is the best choice. In other cases,
the underlined section has obvious or subtle errors that require correction. ese questions require
you to be familiar with the stylistic conventions and grammatical rules of standard written English
and to demonstrate your ability to improve incorrect or ine ective expressions. Sentence correction
questions may include English‐language idioms, which are standard constructions not derived from the
most basic rules of grammar and vocabulary, but idioms are not intended to measure any specialized
knowledge of colloquialisms or regionalisms.
You should begin these questions by reading the sentence carefully. Note whether there are any obvious
grammatical errors as you read the underlined section. en read the five answer choices carefully.
If there was a subtle error you did not recognize the first time you read the sentence, it may become
apparent after you have read the answer choices. If the error is still unclear, see whether you can
eliminate some of the answers as being incorrect. Remember that in some cases, the original selection
may be the best answer.
9.1 Basic English Grammar Rules
Sentence correction questions ask you to recognize and potentially correct at least one of the following
grammar rules. However, these rules are not exhaustive. If you are interested in learning more about
English grammar as a way to prepare for the GMAT exam, there are several resources available on the
Internet.
Agreement
Standard English requires elements within a sentence to be consistent. ere are two types of
agreement: noun‐verb and pronoun.
Noun‐verb agreement: Singular subjects take singular verbs, whereas plural subjects take plural verbs.
Examples:
Correct: “I walk to the store.” Incorrect: “I walks to the store.”
Correct: “We go to school.” Incorrect: “We goes to school.”
Correct: “ e number of residents has grown.” Incorrect: “ e number of residents have grown.”
Correct: “ e masses have spoken.” Incorrect: “ e masses has spoken.”
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GMAT® Offi cial Guide 2018
Pronoun agreement: A pronoun must agree with the noun or pronoun it refers to in person, number, and
gender.
Examples:
Correct: “When you dream, you are usually asleep.” Incorrect: “When one dreams, you are usually
asleep.”
Correct: “When the kids went to sleep, they slept like logs.” Incorrect: “When the kids went to sleep, he
slept like a log.”
Diction
Words should be chosen to reflect correctly and e ectively the appropriate part of speech. ere are
several words that are commonly used incorrectly. When answering sentence correction questions, pay
attention to the following conventions.
Among/between: Among is used to refer to relationships involving more than two objects. Between is used
to refer to relationships involving only two objects.
Examples:
Correct: “We divided our winnings among the three of us.” Incorrect: “We divided our winnings
between the three of us.”
Correct: “She and I divided the cake between us.” Incorrect: “She and I divided the cake among us.”
As/like: As can be a preposition meaning “in the capacity of,” but more often is a conjunction of manner
and is followed by a verb. Like is generally used as a preposition, and therefore is followed by a noun, an
object pronoun, or a verb ending in ‐ ing.
Examples:
Correct: “I work as a librarian.” Incorrect: “I work like a librarian.”
Correct: “Do as I say, not as I do.” Incorrect: “Do like I say, not like I do.”
Correct: “It felt like a dream.” Incorrect: “It felt as a dream.”
Correct: “People like you inspire me.” Incorrect: “People as you inspire me.”
Correct: “ ere’s nothing like biking on a warm, autumn day.” Incorrect: “ ere’s nothing as biking on a
warm, autumn day.”
Mass and count words: Mass words are nouns quantified by an amount rather than by a number. Count
nouns can be quantified by a number.
Examples:
Correct: “We bought a loaf of bread.” Incorrect: “We bought one bread.”
Correct: “He wished me much happiness.” Incorrect: “He wished me many happinesses.”
Correct: “We passed many buildings.” Incorrect: “We passed much buildings.”
Pronouns: Myself should not be used as a substitute for I or me .
Examples:
Correct: “Mom and I had to go to the store.” Incorrect: “Mom and myself had to go to the store.”
Correct: “He gave the present to Dad and me.” Incorrect: “He gave the present to Dad and myself.”
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Grammatical Construction
Good grammar requires complete sentences. Be on the lookout for improperly formed constructions.
Fragments: Parts of a sentence that are disconnected from the main clause are called fragments.
Examples:
Correct: “We saw the doctor and his nurse at the party.” Incorrect: “We saw the doctor at the party. And
his nurse.”
Run‐on sentences: A run‐on sentence is two or more independent clauses that run together without
proper punctuation.
Examples:
Correct: “Jose Canseco is still a feared batter; most pitchers don’t want to face him.” Incorrect: “Jose
Canseco is still a feared batter most pitchers don’t want to face him.”
Constructions: Avoid wordy, redundant constructions.
Examples:
Correct: “We could not come to the meeting because of a conflict.” Incorrect: “ e reason we could not
come to the meeting is because of a conflict.”
Idiom
It is important to avoid nonstandard expressions, although English idioms sometimes do not follow
conventional grammatical rules. Be careful to use the correct idiom when using the constructions and
parts of speech.
Prepositions: Specific prepositions have specific purposes.
Examples:
Correct: “She likes to jog in the morning.” Incorrect: “She likes to jog on the morning.”
Correct: “ ey ranged in age from 10 to 15.” Incorrect: “ ey ranged in age from 10 up to 15.”
Correlatives: Word combinations such as “not only … but also” should be followed by an element of the
same grammatical type.
Examples:
Correct: “I have called not only to thank her but also to tell her about the next meeting.” Incorrect: “I
have called not only to thank her but also I told her about the next meeting.”
Forms of comparison: Many forms follow precise constructions. Fewer refers to a specific number, whereas
less than refers to a continuous quantity. Between … and is the correct form to designate a choice. Farther
refers to distance, whereas further refers to degree.
Examples:
Correct: “ ere were fewer children in my class this year.” Incorrect: “ ere were less children in my
class this year.”
Correct: “ ere was less devastation than I was told.” Incorrect: “ ere was fewer devastation than I was
told.”
Correct: “We had to choose between chocolate and vanilla.” Incorrect: “We had to choose between
chocolate or vanilla.” (It is also correct to say, “We had to choose chocolate or vanilla.”)
Correct: “I ran farther than John, but he took his weight training further than I did.”
Incorrect: “I ran further than John, but he took his weight training farther than I did.”
9.1 Sentence Correction Basic English Grammar Rules
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Logical Predication
Watch out for phrases that detract from the logical argument.
Modification problems: Modifiers should be positioned so it is clear what word or words they are meant
to modify. If modifiers are not positioned clearly, they can cause illogical references or comparisons, or
distort the meaning of the statement.
Examples:
Correct: “I put the cake that I baked by the door.” Incorrect: “I put the cake by the door that I baked.”
Correct: “Reading my mind, she gave me the delicious cookie.” Incorrect: “Reading my mind, the cookie
she gave me was delicious.”
Correct: “In the Middle Ages, the world was believed to be flat.” Incorrect: “In the Middle Ages, the
world was flat.”
Parallelism
Constructing a sentence that is parallel in structure depends on making sure that the di erent
elements in the sentence balance each other; this is a little bit like making sure that the two sides of a
mathematical equation are balanced. To make sure that a sentence is grammatically correct, check to
ensure that phrases, clauses, verbs, and other sentence elements parallel each other.
Examples:
Correct: “I took a bath, went to sleep, and woke up refreshed.” Incorrect: “I took a bath, sleeping, and
waking up refreshed.”
Correct: “ e only way to know is to take the plunge.” Incorrect: “ e only way to know is taking the
plunge.”
Rhetorical Construction
Good sentence structure avoids constructions that are awkward, wordy, redundant, imprecise, or unclear,
even when they are free of grammatical errors.
Examples:
Correct: “Before we left on vacation, we watered the plants, checked to see that the stove was o , and
set the burglar alarm.” Incorrect: “Before we left to go on vacation, we watered, checked to be sure that
the stove had been turned o , and set it.”
Verb Form
In addition to watching for problems of agreement or parallelism, make sure that verbs are used in the
correct tense. Be alert to whether a verb should reflect past, present, or future tense.
Examples:
Correct: “I went to school yesterday.” “I go to school every weekday.” “I will go to school tomorrow.”
Each tense also has a perfect form (used with the past participle—e.g., walked, ran), a progressive form
(used with the present participle—e.g., walking, running), and a perfect progressive form (also used with
the present participle—e.g., walking, running).
Present perfect: Used with has or have, the present perfect tense describes an action that occurred at an
indefinite time in the past or that began in the past and continues into the present.
Examples:
Correct: “I have traveled all over the world.” (at an indefinite time)
Correct: “He has gone to school since he was five years old.” (continues into the present)
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Past perfect: is verb form is used with had to show the order of two events that took place in the past.
Example:
Correct: “By the time I left for school, the cake had been baked.”
Future perfect: Used with will have, this verb form describes an event in the future that will precede
another event.
Example:
Correct: “By the end of the day, I will have studied for all my tests.”
Present progressive: Used with am, is , or are, this verb form describes an ongoing action that is happening
now.
Examples:
Correct: “I am studying for exams.” “ e student is studying for exams.” “We are studying for exams.”
Past progressive: Used with was or were, this verb form describes something that was happening when
another action occurred.
Examples:
Correct: “ e student was studying when the fire alarm rang.” “ ey were studying when the fire broke
out.”
Future progressive: Used with will be or shall be, this verb tense describes an ongoing action that will
continue into the future.
Example:
Correct: “ e students will be studying for exams throughout the month of December.”
Present perfect progressive: Used with have been or has been , this verb tense describes something that
began in the past, continues into the present, and may continue into the future.
Example:
Correct: “ e student has been studying hard in the hope of acing the test.”
Past perfect progressive: Used with had been, this verb form describes an action of some duration that was
completed before another past action occurred.
Example:
Correct: “Before the fire alarm rang, the student had been studying.”
Future perfect progressive: Used with will have been , this verb form describes a future, ongoing action that
will occur before a specified time.
Example:
Correct: “By the end of next year, the students will have been studying math for five years.”
9.1 Sentence Correction Basic English Grammar Rules
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9.2 Study Suggestions
ere are two basic ways you can study for sentence correction questions:
• Read material that reflects standard usage.
One way to gain familiarity with the basic conventions of standard written English is simply to
read. Suitable material will usually be found in good magazines and nonfiction books, editorials in
outstanding newspapers, and the collections of essays used by many college and university writing
courses.
• Review basic rules of grammar and practice with writing exercises.
Begin by reviewing the grammar rules laid out in this chapter. en, if you have school
assignments (such as essays and research papers) that have been carefully evaluated for
grammatical errors, it may be helpful to review the comments and corrections.
9.3 What Is Measured
Sentence correction questions test three broad aspects of language proficiency:
• Correct expression
A correct sentence is grammatically and structurally sound. It conforms to all the rules of standard
written English, including noun‐verb agreement, noun‐pronoun agreement, pronoun consistency,
pronoun case, and verb tense sequence. A correct sentence will not have dangling, misplaced,
or improperly formed modifiers; unidiomatic or inconsistent expressions; or faults in parallel
construction.
• Effective expression
An e ective sentence expresses an idea or relationship clearly and concisely as well as
grammatically. is does not mean that the choice with the fewest and simplest words is
necessarily the best answer. It means that there are no superfluous words or needlessly complicated
expressions in the best choice.
• Proper diction
An e ective sentence also uses proper diction. (Diction refers to the standard dictionary meanings
of words and the appropriateness of words in context.) In evaluating the diction of a sentence, you
must be able to recognize whether the words are well chosen, accurate, and suitable for the context.
9.4 Test-Taking Strategies
1. Read the entire sentence carefully.
Try to understand the specific idea or relationship that the sentence should express.
2. Evaluate the underlined passage for errors and possible corrections before reading
the answer choices.
is strategy will help you discriminate among the answer choices. Remember, in some cases the
underlined passage is correct.
3. Read each answer choice carefully.
e first answer choice always repeats the underlined portion of the original sentence. Choose this
answer if you think that the sentence is best as originally written, but do so only after examining all
the other choices.
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4. Try to determine how to correct what you consider to be wrong with the original
sentence.
Some of the answer choices may change things that are not wrong, whereas others may not
change everything that is wrong.
5. Make sure that you evaluate the sentence and the choices thoroughly.
Pay attention to general clarity, grammatical and idiomatic usage, economy and precision of
language, and appropriateness of diction.
6. Read the whole sentence, substituting the choice that you prefer for the
underlined passage.
A choice may be wrong because it does not fit grammatically or structurally with the rest of the
sentence. Remember that some sentences will require no correction. When the given sentence
requires no correction, choose the first answer.
9.5 The Directions
ese are the directions that you will see for sentence correction questions when you take the GMAT
exam. If you read them carefully and understand them clearly before going to sit for the test, you
will not need to spend too much time reviewing them once you are at the test center and the test is
under way.
Sentence correction questions present a sentence, part or all of which is underlined. Beneath the
sentence, you will find five ways of phrasing the underlined passage. e first answer choice repeats
the original underlined passage; the other four are di erent. If you think the original phrasing is best,
choose the first answer; otherwise, choose one of the others.
is type of question tests your ability to recognize the correctness and e ectiveness of expression in
standard written English. In choosing your answer, follow the requirements of standard written English;
that is, pay attention to grammar, choice of words, and sentence construction. Choose the answer that
produces the most e ective sentence; this answer should be clear and exact, without awkwardness,
ambiguity, redundancy, or grammatical error.
9.5 Sentence Correction The Directions
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668. In a review of 2,000 studies of human behavior that
date back to the 1940s, two Swiss psychologists,
declaring that since most of the studies had failed to
control for such variables as social class and family
size, none could be taken seriously.
(A) psychologists, declaring that since most of the
studies had failed to control for such variables as
social class and family size,
(B) psychologists, declaring that most of the studies
failed in not controlling for such variables like
social class and family size, and
(C) psychologists declared that since most of
the studies, having failed to control for such
variables as social class and family size,
(D) psychologists declared that since most of the
studies fail in controlling for such variables like
social class and family size,
(E) psychologists declared that since most of the
studies had failed to control for variables such as
social class and family size,
669. In her presentation, the head of the Better Business
Bureau emphasized that companies should think of the
cost of conventions and other similar gatherings as not
an expense, but as an investment in networking that
will pay dividends.
(A) as not an expense, but as
(B) as not expense but
(C) not an expense, rather
(D) not as an expense, but as
(E) not in terms of expense, but
670. Recent interdisciplinary studies advance the argument
that emotions, including those deemed personal
or private is a social phenomenon, though one
inseparable from bodily response.
(A) private is a social phenomenon, though one
inseparable
(B) private, are social phenomena that are inseparable
(C) private are a social phenomenon but are not
those separable
(D) private—are social phenomena but not separable
(E) also as private emotions, are social phenomena
not inseparable
671. Manufacturers rate batteries in watt‐hours; if they rate
the watt‐hour higher, the longer the battery can be
expected to last.
(A) if they rate the watt‐hour higher, the longer
(B) rating the watt‐hour higher, it is that much longer
(C) the higher the watt‐hour rating, the longer
(D) the higher the watt‐hour rating, it is that much
longer that
(E) when the watt‐hour rating is higher, the longer it is
672. At the end of the 1930s, Duke Ellington was looking
for a composer to assist him—someone not only who
could arrange music for his successful big band, but
mirroring his eccentric writing style as well in order
to nish the many pieces he had started but never
completed.
(A) someone not only who could arrange music
for his successful big band, but mirroring his
eccentric writing style as well in order to nish
(B) someone who could not only arrange music
for his successful big band, but also mirror his
eccentric writing style in order to nish
9.6 Practice Questions
Each of the sentence correction questions presents a sentence, part or all of which is underlined.
Beneath the sentence you will fi nd fi ve ways of phrasing the underlined part. The fi rst of these repeats
the original; the other four are different. Follow the requirements of standard written English to choose
your answer, paying attention to grammar, word choice, and sentence construction. Select the answer
that produces the most effective sentence; your answer should make the sentence clear, exact, and free
of grammatical error. It should also minimize awkwardness, ambiguity, and redundancy.
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(C) someone who not only could arrange music for
his successful big band, but also to mirror his
eccentric writing style in nishing
(D) that being someone who could not only arrange
music for his successful big band, but mirroring
his eccentric writing style for nishing
(E) being someone not only who could arrange
music for his successful big band, but mirror his
eccentric writing style as well, nishing
673. While Noble Sissle may be best known for his
collaboration with Eubie Blake, as both a vaudeville
performer and as a lyricist for songs and Broadway
musicals, also enjoying an independent career as a
singer with such groups as Hahn’s Jubilee Singers.
(A) and as a lyricist for songs and Broadway
musicals, also enjoying
(B) and writing lyrics for songs and Broadway
musicals, also enjoying
(C) and a lyricist for songs and Broadway musicals,
he also enjoyed
(D) as well as writing lyrics for songs and Broadway
musicals, he also enjoyed
(E) as well as a lyricist for songs and Broadway
musicals, he had also enjoyed
674. Air traf c routes over the North Pole are currently used
by only two or three planes a day, but it was found
by a joint Canadian–Russian study to be both feasible
as well as desirable if those routes are opened to
thousands more commercial planes a year.
(A) Air traf c routes over the North Pole are
currently used by only two or three planes a day,
but it was found by a joint Canadian–Russian
study to be both feasible as well as desirable
if those routes are opened to thousands more
commercial planes a year.
(B) Currently used by only two or three planes a day,
a joint Canadian–Russian study has found that if
air traf c routes over the North Pole are opened
to thousands more commercial planes a year, it
would be both feasible and desirable.
(C) A joint Canadian–Russian study, nding it to be
both feasible as well as desirable to open air
traf c routes over the North Pole, which are
currently used by only two or three planes a day,
to thousands more commercial planes a year.
(D) Although air traf c routes over the North Pole
are currently used by only two or three planes a
day, a joint Canadian–Russian study has found
that opening those routes to thousands more
commercial planes a year is both feasible and
desirable.
(E) With air traf c routes over the North Pole
currently used by only two or three planes a
day, opening those routes to thousands more
commercial planes a year has been found by a
joint Canadian—Russian study as both feasible
and desirable.
675. From an experiment using special extrasensory
perception cards, each bearing one of a set of
symbols, parapsychologist Joseph Banks Rhine
claimed statistical proof for subjects who could use
thought transference to identify a card in the dealer’s
hand.
(A) for subjects who could use thought transference
to identify a card in the dealer’s hand
(B) for a card in the dealer’s hand to be identi ed by
subjects with thought transference
(C) of subjects able to identify with thought
transference a card in the dealer’s hand
(D) that subjects could identify a card in the dealer’s
hand by using thought transference
(E) that subjects are capable to use thought
transference for identifying a card in the dealer’s
hand
676. A long‐term study of some 1,000 physicians indicates
that the more coffee these doctors drank, the more
they had a likelihood of coronary disease.
(A) more they had a likelihood of coronary disease
(B) more was their likelihood of having coronary
disease
(C) more they would have a likelihood to have
coronary disease
(D) greater was their likelihood of having coronary
disease
(E) greater was coronary disease likely
9.6 Sentence Correction Practice Questions
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677. The intricate structure of the compound insect eye,
having hundreds of miniature eyes called ommatidia,
help explain why scientists have assumed that it
evolved independently of the vertebrate eye.
(A) having hundreds of miniature eyes called
ommatidia, help explain why scientists have
assumed that it
(B) having hundreds of miniature eyes that are called
ommatidia, helps explain why scientists have
assumed that they
(C) with its hundreds of miniature eyes that are
called ommatidia, helps explain scientists’
assuming that they
(D) with its hundreds of miniature eyes called
ommatidia, help explain scientists’ assuming that it
(E) with its hundreds of miniature eyes called
ommatidia, helps explain why scientists have
assumed that it
678. In 1979 lack of rain reduced India’s rice production
to about 41 million tons, nearly 25 percent less than
those of the 1978 harvest.
(A) less than those of the 1978 harvest
(B) less than the 1978 harvest
(C) less than 1978
(D) fewer than 1978
(E) fewer than that of India’s 1978 harvest
679. Hurricanes at rst begin traveling from east to west,
because that direction is the way the prevailing winds
in the tropics blow, but they then veer off toward
higher latitudes, in many cases changing direction
toward the east before dissipating over the colder,
more northerly waters or over land.
(A) Hurricanes at rst begin traveling from east
to west, because that direction is the way the
prevailing winds in the tropics blow, but
(B) At rst, hurricanes travel from east to west,
because that is the direction of the prevailing
winds in the tropics, but
(C) While hurricanes travel from east to west at rst,
the direction of the prevailing winds blowing in
the tropics, and
(D) Because hurricanes at rst travel from east to
west, since it is the direction of the prevailing
winds in the tropics,
(E) Hurricanes, beginning by traveling from east
to west, because this is the direction of the
prevailing winds in the tropics,
680. Unlike the virginal, whose single set of strings runs
parallel to the front edge of the instrument, the
harpsichord’s several sets of strings are placed at right
angles to its front edge.
(A) whose single set of strings runs parallel to the
front edge of the instrument, the harpsichord’s
several sets of strings are
(B) with a single set of strings running parallel to the
front edge of the instrument, the several sets of
strings of the harpsichord are
(C) which has a single set of strings that runs
parallel to the front edge of the instrument, in the
case of the harpsichord, several sets of strings
are
(D) which has a single set of strings that run
parallel to the front edge of the instrument, the
harpsichord has several sets of strings
(E) in which a single set of strings run parallel to the
front edge of the instrument, the harpsichord’s
several sets of strings are
681. Although Alice Walker published a number of essays,
poetry collections, and stories during the 1970s, her
third novel, The Color Purple , which was published in
1982, brought her the widest acclaim in that it won
both the National Book Award as well as the Pulitzer
Prize.
(A) which was published in 1982, brought her the
widest acclaim in that it won both the National
Book Award as well as the Pulitzer Prize
(B) published in 1982, bringing her the widest
acclaim by winning both the National Book Award
and the Pulitzer Prize
(C) published in 1982, brought her the widest
acclaim, winning both the National Book Award
and the Pulitzer Prize
(D) was published in 1982 and which, winning both
the National Book Award and the Pulitzer Prize,
brought her the widest acclaim
(E) was published in 1982, winning both the National
Book Award as well as the Pulitzer Prize, and
bringing her the widest acclaim
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682. Many experts regarded the large increase in credit
card borrowing in March not as a sign that households
were pressed for cash and forced to borrow, rather
a sign of con dence by households that they could
safely handle new debt.
(A) rather a sign of con dence by households that
they could safely
(B) yet as a sign of households’ con dence that it
was safe for them to
(C) but a sign of con dence by households that they
could safely
(D) but as a sign that households were con dent
they could safely
(E) but also as a sign that households were
con dent in their ability safely to
683. A pioneer journalist, Nellie Bly’s exploits included
circling the globe faster than Jules Verne’s ctional
Phileas Fogg.
(A) A pioneer journalist, Nellie Bly’s exploits included
(B) The exploits of Nellie Bly, a pioneer journalist,
included
(C) Nellie Bly was a pioneer journalist including in her
exploits the
(D) Included in the pioneer journalist Nellie Bly’s
exploits are
(E) The pioneer journalist’s exploits of Nellie Bly
included
684. In 1913, the largely self-taught Indian mathematician
Srinivasa Ramanujan mailed 120 of his theorems to
three different British mathematicians; only one, G. H.
Hardy, recognized the brilliance of these theorems,
but thanks to Hardy’s recognition, Ramanujan was
eventually elected to the Royal Society of London.
(A) only one, G. H. Hardy, recognized the brilliance
of these theorems, but
(B) they were brilliant, G. H. Hardy alone recognized,
but
(C) these theorems were brilliant, but only one, G. H.
Hardy recognized;
(D) but, only one, G. H. Hardy, recognizing their
brilliance,
(E) only one G. H. Hardy recognized, but these
theorems were brilliant
685. Cost cutting and restructuring has allowed the
manufacturing company to lower its projected losses
for the second quarter, and they are forecasting a
pro t before the end of the year.
(A) has allowed the manufacturing company to lower
its projected losses for the second quarter, and
they are forecasting
(B) has allowed for the manufacturing company to
lower its projected losses in the second quarter
and to forecast
(C) have allowed that the manufacturing company
can lower the projected losses for the second
quarter, and to forecast
(D) have allowed the manufacturing company to
lower its projected second-quarter losses and to
forecast
(E) have allowed for the manufacturing company to
lower the projected losses in the second quarter,
as well as forecasting
686. The Life and Casualty Company hopes that by
increasing its environmental fund reserves to $1.2
billion, that it has set aside enough to pay for
environmental claims and no longer has to use its
pro ts and capital to pay those claims bit by bit, year
by year.
(A) that it has set aside enough to pay for
environmental claims and no longer has
(B) enough has been set aside with which environmental
claims can be paid and it will have no longer
(C) it has set aside enough for payment of
environmental claims and thus no longer having
(D) enough has been set aside to pay for
environmental claims, thus no longer having
(E) it has set aside enough to pay for environmental
claims and will no longer have
9.6 Sentence Correction Practice Questions
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687. Like ancient Egyptian architectural materials that
were recycled in the construction of ancient Greek
Alexandria, so ancient Greek materials from the
construction of that city were reused in subsequent
centuries by Roman, Muslim, and modern builders.
(A) Like ancient Egyptian architectural materials that
were recycled in the construction of
(B) Like recycling ancient Egyptian architectural
materials to construct
(C) Just as ancient Egyptian architectural materials
were recycled in the construction of
(D) Just as they recycled ancient Egyptian
architectural materials in constructing
(E) Just like ancient Egyptian architectural materials
that were recycled in constructing
688. Especially in the early years, new entrepreneurs may
need to nd resourceful ways, like renting temporary
of ce space or using answering services, that make
their company seem large and more rmly established
than they may actually be.
(A) that make their company seem large
(B) to make their companies seem larger
(C) thus making their companies seem larger
(D) so that the companies seem larger
(E) of making their company seem large
689. Unlike the nests of leaf cutters and most other ants,
situated underground or in pieces of wood, raider
ants make a portable nest by entwining their long
legs to form “curtains” of ants that hang from logs or
boulders, providing protection for the queen and the
colony larvae and pupae.
(A) the nests of leaf cutters and most other ants,
(B) the nests of leaf cutters and most other ants,
which are
(C) leaf cutters and most other ants, whose nests are
(D) leaf cutters and most other ants in having nests
(E) those of leaf cutters and most other ants with nests
690. Turtles, like other reptiles, can endure long fasts,
in their ability to survive on weekly or even monthly
feedings; however, when food is readily available, they
may eat frequently and grow very fat.
(A) fasts, in their ability to survive
(B) fasts, having their ability to survive
(C) fasts, due to having the ability of surviving
(D) fasts because they are able to survive
(E) fasts because of having the ability of surviving
691. Thai village crafts, as with other cultures, have
developed through the principle that form follows
function and incorporate readily available materials
fashioned using traditional skills.
(A) as with
(B) as did those of
(C) as they have in
(D) like in
(E) like those of
692. Tropical bats play important roles in the rain forest
ecosystem, aiding in the dispersal of cashew, date,
and g seeds; pollinating banana, breadfruit, and
mango trees; and indirectly help produce tequila by
pollinating agave plants.
(A) pollinating banana, breadfruit, and mango trees;
and indirectly help produce
(B) pollinating banana, breadfruit, and mango trees;
and indirectly helping to produce
(C) pollinating banana, breadfruit, and mango trees;
and they indirectly help to produce
(D) they pollinate banana, breadfruit, and mango
trees; and indirectly help producing
(E) they pollinate banana, breadfruit, and mango
trees; indirectly helping the producing of
693. Discussion of greenhouse effects have usually had
as a focus the possibility of Earth growing warmer
and to what extent it might, but climatologists have
indicated all along that precipitation, storminess, and
temperature extremes are likely to have the greatest
impact on people.
(A) Discussion of greenhouse effects have usually
had as a focus the possibility of Earth growing
warmer and to what extent it might,
(B) Discussion of greenhouse effects has usually
had as its focus whether Earth would get warmer
and what the extent would be,
(C) Discussion of greenhouse effects has usually
focused on whether Earth would grow warmer
and to what extent,
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(D) The discussion of greenhouse effects have
usually focused on the possibility of Earth getting
warmer and to what extent it might,
(E) The discussion of greenhouse effects has usually
focused on whether Earth would grow warmer
and the extent that is,
694. In the seventh century B.C., the Roman alphabet was
adapted from the Etruscan alphabet, which in turn had
been adapted in the previous century from a western
Greek alphabet, which itself had been adapted earlier
in the same century from the Phoenician alphabet.
(A) which itself had been adapted earlier
(B) adapting itself earlier
(C) itself being adapted earlier
(D) having been earlier adapted itself
(E) earlier itself having been adapted
695. With corn, soybean, and wheat reserves being low
enough so a poor harvest would send prices sky-
rocketing, grain futures brokers and their clients are
especially interested in weather that could affect crops.
(A) being low enough so
(B) so low such that
(C) so low that
(D) that are low enough so
(E) that are so low such that
696. By 1940, the pilot Jacqueline Cochran held seventeen
of cial national and international speed records,
and she earned them at a time when aviation was
still so new for many of the planes she ew to be of
dangerously experimental design.
(A) and she earned them at a time when aviation was
still so new for many of the planes she ew to be
(B) earning them at a time that aviation was still so
new for many of the planes she ew to be
(C) earning these at a time where aviation was still
so new that many of the planes she ew were
(D) earned at a time in which aviation was still so
new such that many of the planes she ew were
(E) earned at a time when aviation was still so new
that many of the planes she ew were
697. The foundation works to strengthen local and
regional agricultural markets and cooperating with
governments, improving access for farmers for
productive resources such as land and credit.
(A) cooperating with governments, improving access
for farmers for
(B) cooperates with governments to improve access
for farmers to
(C) cooperate with governments for improvements
of access for farmers to
(D) cooperate with governments and improve
accessibility for farmers for their
(E) in cooperation with governments to improve
access for farmers for
698. A professor at the university has taken a sabbatical to
research on James Baldwin’s books that Baldwin wrote
in France while he was living there .
(A) on James Baldwin’s books that Baldwin wrote in
France while he was living there
(B) about the books James Baldwin wrote in France
(C) into James Baldwin’s books written while in
France
(D) on the books of James Baldwin, written while he
lived in France
(E) the books James Baldwin wrote while he lived in
France
699. Researchers now regard interferon as not a single
substance, but it is rather a biological family of
complex molecules that play an important, though not
entirely de ned, role in the immune system.
(A) as not a single substance, but it is rather a
biological family of complex molecules that play
(B) as not a single substance but as a biological
family of complex molecules playing
(C) not as a single substance but as a biological
family of complex molecules that play
(D) not to be a single substance but rather a
biological family of complex molecules playing
(E) not as a single substance but instead as being a
biological family of complex molecules that play
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700. The remarkable similarity of Thule artifacts throughout
a vast region can, in part, be explained as a very rapid
movement of people from one end of North America to
the other.
(A) The remarkable similarity of Thule artifacts
throughout a vast region can, in part, be
explained as
(B) Thule artifacts being remarkably similar
throughout a vast region, one explanation is
(C) That Thule artifacts are remarkably similar
throughout a vast region is, in part, explainable as
(D) One explanation for the remarkable similarity of
Thule artifacts throughout a vast region is that
there was
(E) Throughout a vast region Thule artifacts are
remarkably similar, with one explanation for this
being
701. The widely accepted big bang theory holds that the
universe began in an explosive instant ten to twenty
billion years ago and has been expanding ever since.
(A) that the universe began in an explosive instant
ten to twenty billion years ago and has been
expanding
(B) that the universe had begun in an explosive
instant ten to twenty billion years ago and had
been expanding
(C) that the beginning of the universe was an
explosive instant ten to twenty billion years ago
that has expanded
(D) the beginning of the universe to have been an
explosive instant ten to twenty billion years ago
that is expanding
(E) the universe to have begun in an explosive
instant ten to twenty billion years ago and has
been expanding
702. Between 14,000 and 8,000 B.C. the ice cap that
covered northern Asia, Europe, and America began
to melt, uncovering vast new areas that were to be
occupied by migrating peoples moving northward.
(A) began to melt, uncovering vast new areas that
were to be occupied
(B) began melting, to uncover vast new areas to be
occupied
(C) began, by melting, to uncover vast new areas for
occupation
(D) began, after melting, uncovering vast new areas
which are to be occupied
(E) would begin to uncover, through melting, vast
new areas for occupation
703. Bengal‐born writer, philosopher, and educator
Rabindranath Tagore had the greatest admiration
for Mohandas K. Gandhi the person and also as a
politician, but Tagore had been skeptical of Gandhi’s
form of nationalism and his conservative opinions
about India’s cultural traditions.
(A) for Mohandas K. Gandhi the person and also as
a politician, but Tagore had been
(B) for Mohandas K. Gandhi as a person and as a
politician, but Tagore was also
(C) for Mohandas K. Gandhi not only as a person
and as a politician, but Tagore was also
(D) of Mohandas K. Gandhi as a person and as also
a politician, but Tagore was
(E) of Mohandas K. Gandhi not only as a person and
as a politician, but Tagore had also been
704. Traf c safety of cials predict that drivers will be
equally likely to exceed the proposed speed limit as
the current one.
(A) equally likely to exceed the proposed speed limit
as
(B) equally likely to exceed the proposed speed limit
as they are
(C) equally likely that they will exceed the proposed
speed limit as
(D) as likely that they will exceed the proposed
speed limit as
(E) as likely to exceed the proposed speed limit as
they are
705. Written early in the French Revolution, Mary
Wollstonecraft’s A Vindication of the Rights of Man
(1790) and A Vindication of the Rights of Woman
(1792) attributed Europe’s social and political ills to be
the result of the dominance of aristocratic values and
patriarchal hereditary privilege.
(A) Mary Wollstonecraft’s A Vindication of the Rights
of Man (1790) and A Vindication of the Rights
of Woman (1792) attributed Europe’s social and
political ills to be the result of
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(B) Mary Wollstonecraft’s A Vindication of the Rights
of Man (1790) and A Vindication of the Rights
of Woman (1792) attributed Europe’s social and
political ills to result from
(C) Mary Wollstonecraft’s A Vindication of the Rights
of Man (1790) and A Vindication of the Rights
of Woman (1792) attributed Europe’s social and
political ills to
(D) in A Vindication of the Rights of Man (1790) and
A Vindication of the Rights of Woman (1792),
Mary Wollstonecraft attributed Europe’s social
and political ills to have been the result of
(E) Mary Wollstonecraft, in A Vindication of the
Rights of Man (1790) and A Vindication of the
Rights of Woman (1792), attributed Europe’s
social and political ills to
706. Using study groups managed by the principal popular
organizations and political parties, the Swedish public
was informed by the government about energy and
nuclear power .
(A) the Swedish public was informed by the
government about energy and nuclear power
(B) the government informed the Swedish public
about energy and nuclear power
(C) energy and nuclear power information was given
to the Swedish public by the government
(D) information about energy and nuclear power was
given to the Swedish public by the government
(E) the public of Sweden was given energy and
nuclear power information by the government
707. The use of the bar code, or Universal Product Code,
which was created in part to enable supermarkets to
process customers at a faster rate, has expanded
beyond supermarkets to other retail outlets and
have become readily accepted despite some initial
opposition when it was rst introduced in 1974 .
(A) have become readily accepted despite some initial
opposition when it was rst introduced in 1974
(B) has become readily accepted despite some
initial opposition when they were rst introduced
in 1974
(C) have become readily accepted despite some
initial opposition when rst introduced in 1974
(D) has become readily accepted despite some
initial opposition when the bar code was rst
introduced in 1974
(E) bar codes have become readily accepted
despite some initial opposition when it was rst
introduced in 1974
708. The Organization of Petroleum Exporting Countries
(OPEC) had long been expected to announce a
reduction in output to bolster sagging oil prices, but
of cials of the organization just recently announced
that the group will pare daily production by 1.5 million
barrels by the beginning of next year, but only if
non‐OPEC nations, including Norway, Mexico, and
Russia, were to trim output by a total of 500,000
barrels a day.
(A) year, but only if non‐OPEC nations, including
Norway, Mexico, and Russia, were to trim output
(B) year, but only if the output of non‐OPEC nations,
which includes Norway, Mexico, and Russia, is
trimmed
(C) year only if the output of non‐OPEC nations,
including Norway, Mexico, and Russia, would be
trimmed
(D) year only if non‐OPEC nations, which includes
Norway, Mexico, and Russia, were trimming
output
(E) year only if non‐OPEC nations, including Norway,
Mexico, and Russia, trim output
709. Not trusting themselves to choose wisely among the
wide array of investment opportunities on the market,
stockbrokers are helping many people who turn to them
to buy stocks that could be easily bought directly.
(A) stockbrokers are helping many people who turn
to them to buy stocks that could be easily
(B) stockbrokers are helping many people who are
turning to them for help in buying stocks that
they could easily have
(C) many people are turning to stockbrokers for help
from them to buy stocks that could be easily
(D) many people are turning to stockbrokers for help
to buy stocks that easily could have been
(E) many people are turning to stockbrokers for help
in buying stocks that could easily be
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710. There are several ways to build solid walls using just
mud or clay, but the most extensively used method
has been the forming of bricks out of mud or clay, and,
after some preliminary air drying or sun drying, they
are laid in the wall in mud mortar.
(A) the forming of bricks out of mud or clay, and,
after some preliminary air drying or sun drying,
they are laid
(B) forming the mud or clay into bricks, and, after
some preliminary air drying or sun drying, to lay
them
(C) having bricks formed from mud or clay, and,
after some preliminary air drying or sun drying,
they were laid
(D) to form the mud or clay into bricks, and, after
some preliminary air drying or sun drying, to lay
them
(E) that bricks were formed from mud or clay, which,
after some preliminary air drying or sun drying,
were laid
711. A surge in new home sales and a drop in weekly
unemployment claims suggest that the economy
might not be as weak as some analysts previously
thought.
(A) claims suggest that the economy might not be
as weak as some analysts previously thought
(B) claims suggests that the economy might not
be so weak as some analysts have previously
thought
(C) claims suggest that the economy might not be
as weak as have been previously thought by
some analysts
(D) claims, suggesting about the economy that it
might not be so weak as previously thought by
some analysts
(E) claims, suggesting the economy might not be
as weak as previously thought to be by some
analysts
712. Retail sales rose 0.8 of 1 percent in August,
intensifying expectations that personal spending in the
July–September quarter more than doubled that of the
1.4 percent growth rate in personal spending for the
previous quarter.
(A) that personal spending in the July–September
quarter more than doubled that of
(B) that personal spending in the July–September
quarter would more than double
(C) of personal spending in the July–September
quarter, that it more than doubled
(D) of personal spending in the July–September
quarter more than doubling that of
(E) of personal spending in the July–September
quarter, that it would more than double that of
713. In the early part of the twentieth century, many
vacationers found that driving automobiles and sleeping
in tents allowed them to enjoy nature close at hand and
tour at their own pace, with none of the restrictions of
passenger trains and railroad timetables or with the
formalities, expenses, and impersonality of hotels.
(A) with none of the restrictions of passenger trains
and railroad timetables or with the
(B) with none of the restrictions of passenger trains,
railroad timetables, nor
(C) without the restrictions of passenger trains and
railroad timetables nor
(D) without the restrictions of passenger trains and
railroad timetables or with the
(E) without the restrictions of passenger trains and
railroad timetables or the
714. Over the next few years, increasing demands on the
Chattahoochee River, which ows into the Apalachicola
River, could alter the saline content of Apalachicola
Bay, which would rob the oysters there of their avor,
and to make them decrease in size, less distinctive,
and less in demand.
(A) which would rob the oysters there of their avor,
and to make them decrease in size,
(B) and it would rob the oysters there of their avor,
make them smaller,
(C) and rob the oysters there of their avor, making
them decrease in size,
(D) robbing the oysters there of their avor and
making them smaller,
(E) robbing the oysters there of their avor, and
making them decrease in size,
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715. Elizabeth Barber, the author of both Prehistoric
Textiles , a comprehensive work on cloth in the
early cultures of the Mediterranean, and also of
Women’s Work , a more general account of early cloth
manufacture, is an expert authority on textiles in
ancient societies.
(A) also of Women’s Work , a more general account
of early cloth manufacture, is an expert authority
on
(B) also Women’s Work , a more general account of
cloth manufacture, is an expert authority about
(C) of Women’s Work , a more general account about
early cloth manufacture, is an authority on
(D) of Women’s Work , a more general account about
early cloth manufacture, is an expert authority
about
(E) Women’s Work , a more general account of early
cloth manufacture, is an authority on
716. Digging in sediments in northern China, evidence
has been gathered by scientists suggesting that
complex life‐forms emerged much earlier than they had
previously thought.
(A) evidence has been gathered by scientists
suggesting that complex life‐forms emerged
much earlier than they had
(B) evidence gathered by scientists suggests a
much earlier emergence of complex life‐forms
than had been
(C) scientists have gathered evidence suggesting that
complex life‐forms emerged much earlier than
(D) scientists have gathered evidence that suggests
a much earlier emergence of complex life‐forms
than that which was
(E) scientists have gathered evidence which
suggests a much earlier emergence of complex
life‐forms than that
717. Employing many different techniques throughout his
career, Michelangelo produced a great variety of art
works, including paintings, for example, in the Sistine
Chapel, to sculpture, for example, the statue of David.
(A) including paintings, for example, in the Sistine
Chapel, to sculpture, for example,
(B) including paintings, for example, in the Sistine
Chapel, to sculpture, like
(C) including paintings, such as those in the Sistine
Chapel, and sculpture, as
(D) ranging from paintings, such as those in the
Sistine Chapel, to sculpture, such as
(E) ranging from paintings, such as in the Sistine
Chapel, and sculpture, such as
718. Outlining his strategy for nursing the troubled
conglomerate back to health, the chief executive’s
plans were announced on Wednesday for cutting the
company’s huge debt by selling nearly $12 billion in
assets over the next 18 months.
(A) executive’s plans were announced on Wednesday
for cutting the company’s huge debt by selling
nearly $12 billion in assets over the next
18 months
(B) executive’s plans, which are to cut the company’s
huge debt by selling nearly $12 billion in assets
over the next 18 months, were announced on
Wednesday
(C) executive’s plans for cutting the company’s
huge debt by selling nearly $12 billion in assets
over the next 18 months were announced on
Wednesday
(D) executive announced plans Wednesday to cut the
company’s huge debt by selling nearly $12 billion
in assets over the next 18 months
(E) executive announced plans Wednesday that are
to cut the company’s huge debt by selling nearly
$12 billion in assets over the next 18 months
719. It is called a sea, but the landlocked Caspian is actually
the largest lake on Earth, which covers more than four
times the surface area of its closest rival in size, North
America’s Lake Superior.
(A) It is called a sea, but the landlocked Caspian is
actually the largest lake on Earth, which covers
(B) Although it is called a sea, actually the
landlocked Caspian is the largest lake on Earth,
which covers
(C) Though called a sea, the landlocked Caspian is
actually the largest lake on Earth, covering
(D) Though called a sea but it actually is the largest
lake on Earth, the landlocked Caspian covers
(E) Despite being called a sea, the largest lake on
Earth is actually the landlocked Caspian, covering
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720. Neuroscientists, having amassed a wealth of
knowledge over the past twenty years about the brain
and its development from birth to adulthood, are now
drawing solid conclusions about how the human brain
grows and how babies acquire language.
(A) Neuroscientists, having amassed a wealth of
knowledge over the past twenty years about
the brain and its development from birth to
adulthood, are
(B) Neuroscientists, having amassed a wealth of
knowledge about the brain and its development
from birth to adulthood over the past twenty
years, and are
(C) Neuroscientists amassing a wealth of knowledge
about the brain and its development from birth to
adulthood over the past twenty years, and are
(D) Neuroscientists have amassed a wealth of
knowledge over the past twenty years about the
brain and its development from birth to adulthood,
(E) Neuroscientists have amassed, over the past
twenty years, a wealth of knowledge about the
brain and its development from birth to adulthood,
721. According to a recent study of consumer spending on
prescription medications, increases in the sales of the
50 drugs that were advertised most heavily accounts
for almost half of the $20.8 billion increase in drug
spending last year, the remainder of which came
from sales of the 9,850 prescription medicines that
companies did not advertise or advertised very little.
(A) heavily accounts for almost half of the $20.8
billion increase in drug spending last year, the
remainder of which came
(B) heavily were what accounted for almost half of
the $20.8 billion increase in drug spending last
year; the remainder of the increase coming
(C) heavily accounted for almost half of the $20.8
billion increase in drug spending last year, the
remainder of the increase coming
(D) heavily, accounting for almost half of the $20.8
billion increase in drug spending last year, while
the remainder of the increase came
(E) heavily, which accounted for almost half of the
$20.8 billion increase in drug spending last year,
with the remainder of it coming
722. Along the major rivers that traverse the deserts of
northeast Africa, the Middle East, and northwest India,
the combination of a reliable supply of water and good
growing conditions both encouraged farming traditions
that, in places, endure in at least 6,000 years.
(A) good growing conditions both encouraged
farming traditions that, in places, endure in
(B) good growing conditions encouraged farming
traditions that have, in places, endured for
(C) of good growing conditions have encouraged
farming traditions that, in places, endured for
(D) of good growing conditions both encouraged
farming traditions that have, in places, endured
(E) of good growing conditions encouraged farming
traditions that have, in places, been enduring
for
723. Despite its covering the entire planet, Earth has a
crust that is not seamless or stationary, rather it is
fragmented into mobile semirigid plates.
(A) Despite its covering the entire planet, Earth has
a crust that is not seamless or stationary, rather
it is
(B) Despite the fact that it covers the entire planet,
Earth’s crust is neither seamless nor is it
stationary, but is
(C) Despite covering the entire planet, Earth’s crust
is neither seamless nor is it stationary, but
rather
(D) Although it covers the entire planet, Earth’s
crust is neither seamless nor stationary, but
rather
(E) Although covering the entire planet, Earth has a
crust that is not seamless or stationary, but
724. Emily Dickinson’s letters to Susan Huntington Dickinson
were written over a period beginning a few years
before Susan’s marriage to Emily’s brother and ending
shortly before Emily’s death in 1886, outnumbering her
letters to anyone else.
(A) Dickinson were written over a period beginning
a few years before Susan’s marriage to Emily’s
brother and ending shortly before Emily’s death
in 1886, outnumbering
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(B) Dickinson were written over a period that begins
a few years before Susan’s marriage to Emily’s
brother and ended shortly before Emily’s death in
1886, outnumber
(C) Dickinson, written over a period beginning a few
years before Susan’s marriage to Emily’s brother
and that ends shortly before Emily’s death in
1886 and outnumbering
(D) Dickinson, which were written over a period
beginning a few years before Susan’s marriage
to Emily’s brother, ending shortly before Emily’s
death in 1886, and outnumbering
(E) Dickinson, which were written over a period
beginning a few years before Susan’s marriage
to Emily’s brother and ending shortly before
Emily’s death in 1886, outnumber
725. At the end of 2001, motion picture industry
representatives said that there were about a million
copies of Hollywood movies available online and
expected piracy to increase with high‐speed Internet
connections that become more widely available .
(A) online and expected piracy to increase with high‐
speed Internet connections that become more
widely available
(B) online and expect the increase of piracy with
the wider availability of high‐speed Internet
connections
(C) online, and they expect more piracy to increase
with the wider availability of high‐speed Internet
connections
(D) online, and that they expected the increase of
piracy as high‐speed Internet connections would
become more widely available
(E) online, and that they expected piracy to increase
as high‐speed Internet connections became
more widely available
726. Making things even more dif cult has been general
market inactivity lately, if not paralysis, which has
provided little in the way of pricing guidance.
(A) has been general market inactivity lately, if not
paralysis, which has provided
(B) there is general market inactivity, if not paralysis,
lately it has provided
(C) general market inactivity, if not paralysis, has
lately provided
(D) lately, general market inactivity, if not paralysis,
has provided
(E) is that lately general market inactivity, if not
paralysis, which provides
727. Unlike the conviction held by many of her colleagues
that genes were relatively simple and static, Barbara
McClintock adhered to her own more complicated
ideas about how genes might operate, and in 1983,
at the age of 81, was awarded a Nobel Prize for her
discovery that the genes in corn are capable of moving
from one chromosomal site to another.
(A) Unlike the conviction held by many of her
colleagues that genes were
(B) Although many of her colleagues were of the
conviction of genes being
(C) Contrary to many of her colleagues being
convinced that genes were
(D) Even though many of her colleagues were
convinced that genes were
(E) Even with many of her colleagues convinced of
genes being
728. Ry–
u nosuke Akutagawa’s knowledge of the literatures of
Europe, China, and that of Japan were instrumental in
his development as a writer, informing his literary style
as much as the content of his ction.
(A) that of Japan were instrumental in his
development as a writer, informing his literary
style as much as
(B) that of Japan was instrumental in his
development as a writer, and it informed both his
literary style as well as
(C) Japan was instrumental in his development as a
writer, informing both his literary style and
(D) Japan was instrumental in his development as a
writer, as it informed his literary style as much
as
(E) Japan were instrumental in his development as a
writer, informing both his literary style in addition
to
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729. According to scientists who monitored its path,
an expanding cloud of energized particles ejected
from the Sun recently triggered a large storm in the
magnetic eld that surrounds Earth, which brightened
the Northern Lights and also possibly knocking out a
communications satellite.
(A) an expanding cloud of energized particles
ejected from the Sun recently triggered a large
storm in the magnetic eld that surrounds Earth,
which brightened the Northern Lights and also
possibly knocking
(B) an expanding cloud of energized particles
ejected from the Sun was what recently
triggered a large storm in the magnetic eld that
surrounds Earth, and it brightened the Northern
Lights and also possibly knocked
(C) an expanding cloud of energized particles
ejected from the Sun recently triggered a large
storm in the magnetic eld that surrounds Earth,
brightening the Northern Lights and possibly
knocking
(D) a large storm in the magnetic eld that surrounds
Earth, recently triggered by an expanding cloud
of energized particles, brightened the Northern
Lights and it possibly knocked
(E) a large storm in the magnetic eld surrounding
Earth was recently triggered by an expanding
cloud of energized particles, brightening the
Northern Lights and it possibly knocked
730. In 1850, Lucretia Mott published her Discourse on
Women , arguing in a treatise for women to have equal
political and legal rights and for changes in the married
women’s property laws.
(A) arguing in a treatise for women to have equal
political and legal rights
(B) arguing in a treatise for equal political and legal
rights for women
(C) a treatise that advocates women’s equal political
and legal rights
(D) a treatise advocating women’s equal political and
legal rights
(E) a treatise that argued for equal political and legal
rights for women
731. To develop more accurate population forecasts,
demographers have to know a great deal more than now
about the social and economic determinants of fertility.
(A) have to know a great deal more than now about
the social and economic
(B) have to know a great deal more than they do
now about the social and economical
(C) would have to know a great deal more than they
do now about the social and economical
(D) would have to know a great deal more than they
do now about the social and economic
(E) would have to know a great deal more than now
about the social and economic
732. Laos has a land area about the same as Great Britain
but only four million in population, where many are
members of hill tribes ensconced in the virtually
inaccessible mountain valleys of the north.
(A) about the same as Great Britain but only four
million in population, where many
(B) of about the same size as Great Britain is, but
in Laos there is a population of only four million,
and many
(C) that is about the same size as Great Britain’s
land area, but in Laos with a population of only
four million people, many of them
(D) comparable to the size of Great Britain, but only
four million in population, and many
(E) comparable to that of Great Britain but a
population of only four million people, many of
whom
733. Having been named for a mythological nymph who
cared for the infant Jupiter, the asteroid named Ida, in
the middle of the belt of asteroids that orbit the Sun
between Mars and Jupiter, was discovered in 1884.
(A) Having been named for a mythological nymph
who cared for the infant Jupiter, the asteroid
named Ida, in the middle of the belt of asteroids
that orbit the Sun between Mars and Jupiter, was
discovered in 1884.
(B) Discovered in 1884, the asteroid Ida, named for
a mythological nymph who cared for the infant
Jupiter, is in the middle of the belt of asteroids
that orbit the Sun between Mars and Jupiter.
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(C) In the middle of the belt of asteroids that orbit the
Sun between Mars and Jupiter, the asteroid Ida,
discovered in 1884 and named for a mythological
nymph who cared for the infant Jupiter.
(D) The asteroid Ida, named for a mythological
nymph who cared for the infant Jupiter and
discovered in 1884, is in the middle of the belt
of asteroids to orbit the Sun between Mars and
Jupiter.
(E) Ida, an asteroid discovered in 1884 and which
was named for a mythological nymph who cared
for the infant Jupiter, is in the middle of the belt
of asteroids to orbit the Sun between Mars and
Jupiter.
734. In ancient Thailand, much of the local artisans’ creative
energy was expended for the creation of Buddha
images and when they constructed and decorated the
temples that enshrined them.
(A) much of the local artisans’ creative energy was
expended for the creation of Buddha images
and when they constructed and decorated the
temples that enshrined them
(B) much of the local artisans’ creative energy was
expended on the creation of Buddha images and
on construction and decoration of the temples in
which they were enshrined
(C) much of the local artisans’ creative energy was
expended on the creation of Buddha images
as well as constructing and decoration of the
temples in which they were enshrined
(D) creating images of Buddha accounted for
much of the local artisans’ creative energy, and
also constructing and decorating the temples
enshrining them
(E) the creation of Buddha images accounted for
much of the local artisans’ creative energy
as well as construction and decoration of the
temples that enshrined them
735. The English physician Edward Jenner found that if
experimental subjects were deliberately infected with
cowpox, which caused only a mild illness, they are
immune from smallpox.
(A) which caused only a mild illness, they are
immune from
(B) causing only a mild illness, they become immune
from
(C) which causes only a mild illness, they are
immune to
(D) causing only a mild illness, they became immune
from
(E) which caused only a mild illness, they would
become immune to
736. Covering 71 percent of Earth’s surface, the oceans
play an essential role in maintaining the conditions for
human existence on land, moderating temperature
by the absorption of heat and carbon dioxide, and
giving pure water back to the atmosphere through
evaporation.
(A) Covering 71 percent of Earth’s surface, the
oceans play an essential role in maintaining
the conditions for human existence on land,
moderating
(B) Covering 71 percent of Earth’s surface and
playing an essential role in maintaining the
conditions for human existence on land, the
oceans moderate
(C) The oceans cover 71 percent of Earth’s
surface and play an essential role in maintaining
conditions for human existence on land, and by
moderating
(D) The oceans cover 71 percent of Earth’s
surface, play an essential role in maintaining
the conditions for human existence on land, and
moderate
(E) The oceans cover 71 percent of Earth’s surface,
playing an essential role in maintaining the
conditions for human existence on land, and they
moderate
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737. Some anthropologists believe that the genetic
homogeneity evident in the world’s people is the result
of a “population bottleneck”—at some time in the past
our ancestors suffered an event, greatly reducing their
numbers and thus our genetic variation.
(A) at some time in the past our ancestors suffered
an event, greatly reducing their numbers
(B) that at some time in the past our ancestors
suffered an event that greatly reduced their
numbers
(C) that some time in the past our ancestors
suffered an event so that their numbers were
greatly reduced,
(D) some time in the past our ancestors suffered
an event from which their numbers were greatly
reduced
(E) some time in the past, that our ancestors
suffered an event so as to reduce their numbers
greatly,
738. Foraging at all times of the day and night, but
interspersing their feeding with periods of rest that last
between one and eight hours, a sperm whale could eat
so much as a ton of squid a day.
(A) between one and eight hours, a sperm whale
could eat so
(B) between one and eight hours, sperm whales can
eat as
(C) between one to eight hours, sperm whales could
eat as
(D) from one to eight hours, sperm whales could eat
so
(E) from one to eight hours, a sperm whale can eat
so
739. In some types of pine tree, a thick layer of needles
protects the buds from which new growth proceeds;
consequently they are able to withstand forest res
relatively well .
(A) a thick layer of needles protects the buds from
which new growth proceeds; consequently they
are able to withstand forest res relatively well
(B) a thick needle layer protects buds from where
new growth proceeds, so that they can withstand
forest res relatively well
(C) a thick layer of needles protect the buds from
which new growth proceeds; thus, they are able
to withstand relatively well any forest res
(D) since the buds from which new growth
proceeds are protected by a thick needle layer,
consequently they can therefore withstand forest
res relatively well
(E) because the buds where new growth happens
are protected by a thick layer of needles, they
are able to withstand forest res relatively easily
as a result
740. The tourism commission has conducted surveys of
hotels in the most popular resorts, with the ultimate
goal of reducing the guests who end up expressing
overall dissatisfaction with the service in the hotels .
(A) with the ultimate goal of reducing the guests who
end up expressing overall dissatisfaction with the
service in the hotels
(B) with the goal to ultimately reduce the number
of guests who end up expressing overall
dissatisfaction with the hotels’ service
(C) ultimately with the goal to reduce expressions
of overall dissatisfaction by the guests with the
hotel service
(D) in an ultimate attempt to reduce the number
of guests that ends up expressing overall
dissatisfaction with the hotels’ service
(E) with the ultimate goal of reducing the number of
guests who express overall dissatisfaction with
the hotels’ service
741. A new study suggests that the conversational pace of
everyday life may be so brisk it hampers the ability of
some children for distinguishing discrete sounds and
words and, the result is, to make sense of speech.
(A) it hampers the ability of some children for
distinguishing discrete sounds and words and,
the result is, to make
(B) that it hampers the ability of some children to
distinguish discrete sounds and words and, as a
result, to make
(C) that it hampers the ability of some children to
distinguish discrete sounds and words and, the
result of this, they are unable to make
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(D) that it hampers the ability of some children to
distinguish discrete sounds and words, and
results in not making
(E) as to hamper the ability of some children for
distinguishing discrete sounds and words,
resulting in being unable to make
742. The nineteenth‐century chemist Humphry Davy
presented the results of his early experiments in his
“Essay on Heat and Light,” a critique of all chemistry
since Robert Boyle as well as a vision of a new
chemistry that Davy hoped to found.
(A) a critique of all chemistry since Robert Boyle as
well as a vision of a
(B) a critique of all chemistry following Robert Boyle
and also his envisioning of a
(C) a critique of all chemistry after Robert Boyle and
envisioning as well
(D) critiquing all chemistry from Robert Boyle
forward and also a vision of
(E) critiquing all the chemistry done since Robert
Boyle as well as his own envisioning of
743. To attract the most talented workers, some companies
are offering a wider range of bene ts, letting
employees pick those most important to them.
(A) bene ts, letting employees pick those most
important to them
(B) bene ts, letting employees pick the most
important of them to themselves
(C) bene ts and letting employees pick the most
important to themselves
(D) bene ts and let employees pick the most
important to them
(E) bene ts and let employees pick those that are
most important to themselves
744. Many of the earliest known images of Hindu deities
in India date from the time of the Kushan Empire,
fashioned either from the spotted sandstone of
Mathura or Gandharan grey schist.
(A) Empire, fashioned either from the spotted
sandstone of Mathura or
(B) Empire, fashioned from either the spotted
sandstone of Mathura or from
(C) Empire, either fashioned from the spotted
sandstone of Mathura or
(D) Empire and either fashioned from the spotted
sandstone of Mathura or from
(E) Empire and were fashioned either from the
spotted sandstone of Mathura or from
745. Tides typically range from three to six feet, but while
some places show no tides at all, some others, such
as the Bay of Fundy, have tides of at least thirty feet
and more.
(A) some others, such as the Bay of Fundy, have
tides of at least thirty feet and more
(B) the others, such as the Bay of Fundy, that have
tides of more than thirty feet
(C) others, such as the Bay of Fundy, have tides of
more than thirty feet
(D) those at the Bay of Fundy, which has tides of
more than thirty feet
(E) the ones at the Bay of Fundy have tides of at
least thirty feet and more
746. A leading gure in the Scottish Enlightenment, Adam
Smith’s two major books are to democratic capitalism
what Marx’s Das Kapital is to socialism.
(A) Adam Smith’s two major books are to
democratic capitalism what
(B) Adam Smith’s two major books are to
democratic capitalism like
(C) Adam Smith’s two major books are to
democratic capitalism just as
(D) Adam Smith wrote two major books that are to
democratic capitalism similar to
(E) Adam Smith wrote two major books that are to
democratic capitalism what
9.6 Sentence Correction Practice Questions
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747. Researchers studying the brain scans of volunteers
who pondered ethical dilemmas have found that the
basis for making tough moral judgments is emotion,
not logic or analytical reasoning.
(A) the brain scans of volunteers who pondered
ethical dilemmas have found that the basis for
making tough moral judgments is
(B) the brain scans of volunteers who pondered
ethical dilemmas and found the basis to make
tough moral decisions to be
(C) the brain scans of volunteers pondering ethical
dilemmas and found that the basis for making
tough moral decisions is
(D) volunteers’ brain scans while pondering ethical
dilemmas have found the basis to make tough
moral judgments to be
(E) volunteers’ brain scans while they pondered
ethical dilemmas have found that the basis for
making tough moral judgments is
748. Rivaling the pyramids of Egypt or even the ancient
cities of the Maya as an achievement, the army of
terra‐cotta warriors created to protect Qin Shi Huang,
China’s rst emperor, in his afterlife is more than 2,000
years old and took 700,000 artisans more than 36
years to complete.
(A) the army of terra‐cotta warriors created to protect
Qin Shi Huang, China’s rst emperor, in his afterlife
is more than 2,000 years old and took 700,000
artisans more than 36 years to complete
(B) Qin Shi Huang, China’s rst emperor, was
protected in his afterlife by an army of terra-
cotta warriors that was created more than
2,000years ago by 700,000 artisans who took
more than 36 years to complete it
(C) it took 700,000 artisans more than 36 years
to create an army of terra‐cotta warriors more
than 2,000 years ago that would protect
Qin Shi Huang, China’s rst emperor, in his afterlife
(D) more than 2,000 years ago, 700,000 artisans
worked more than 36 years to create an army
of terra‐cotta warriors to protect Qin Shi Huang,
China’s rst emperor, in his afterlife
(E) more than 36 years were needed to complete
the army of terra‐cotta warriors that 700,000
artisans created 2,000 years ago to protect Qin
Shi Huang, China’s rst emperor, in his afterlife
749. In California, a lack of genetic variation in the Argentine
ant has allowed the species to spread widely; due to
their being so genetically similar to one another, the ants
consider all their fellows to be a close relative and thus
do not engage in the kind of erce intercolony struggles
that limits the spread of this species in its native Argentina.
(A) due to their being so genetically similar to one
another, the ants consider all their fellows to be
a close relative and thus do not engage in the
kind of erce intercolony struggles that limits
(B) due to its being so genetically similar, the ant
considers all its fellows to be a close relative
and thus does not engage in the kind of erce
intercolony struggles that limit
(C) because it is so genetically similar, the ant
considers all its fellows to be close relatives
and thus does not engage in the kind of erce
intercolony struggles that limits
(D) because they are so genetically similar to one
another, the ants consider all their fellows to be
close relatives and thus do not engage in the
kind of erce intercolony struggles that limit
(E) because of being so genetically similar to one
another, the ants consider all their fellows to be
a close relative and thus do not engage in the
kind of erce intercolony struggles that limits
750. Next month, state wildlife of cials are scheduled to
take over the job of increasing the wolf population in
the federally designated recovery area, the number
of which will however ultimately be dictated by the
number of prey in the area.
(A) area, the number of which will however
(B) area; the size of the population, however, will
(C) area, however the number of wolves will
(D) area; the number of which will, however,
(E) area, when the size of the population will, however,
751. About 5 million acres in the United States have been
invaded by leafy spurge, a herbaceous plant from
Eurasia with milky sap that gives mouth sores to cattle,
displacing grasses and other cattle food and rendering
rangeland worthless.
(A) States have been invaded by leafy spurge, a
herbaceous plant from Eurasia with milky sap
that gives mouth sores to cattle, displacing
grasses and other cattle food and rendering
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(B) States have been invaded by leafy spurge, a
herbaceous plant from Eurasia, with milky sap,
that gives mouth sores to cattle and displaces
grasses and other cattle food, rendering
(C) States have been invaded by leafy spurge, a
herbaceous plant from Eurasia having milky sap
that gives mouth sores to cattle and displacing
grasses and other cattle food, rendering
(D) States, having been invaded by leafy spurge,
a herbaceous plant from Eurasia with milky
sap that gives mouth sores to cattle, displaces
grasses and other cattle food, and renders
(E) States, having been invaded by leafy spurge, a
herbaceous plant from Eurasia that has milky
sap giving mouth sores to cattle and displacing
grasses and other cattle food, rendering
752. While it costs about the same to run nuclear plants as
other types of power plants, it is the xed costs that
stem from building nuclear plants that makes it more
expensive for them to generate electricity.
(A) While it costs about the same to run nuclear plants
as other types of power plants, it is the xed costs
that stem from building nuclear plants that makes it
more expensive for them to generate electricity.
(B) While the cost of running nuclear plants is about the
same as for other types of power plants, the xed
costs that stem from building nuclear plants make
the electricity they generate more expensive.
(C) Even though it costs about the same to run
nuclear plants as for other types of power
plants, it is the xed costs that stem from
building nuclear plants that makes the electricity
they generate more expensive.
(D) It costs about the same to run nuclear plants as for
other types of power plants, whereas the electricity
they generate is more expensive, stemming from
the xed costs of building nuclear plants.
(E) The cost of running nuclear plants is about the
same as other types of power plants, but the
electricity they generate is made more expensive
because of the xed costs stemming from
building nuclear plants.
753. The 32 species that make up the dolphin family are
closely related to whales and in fact include the animal
known as the killer whale, which can grow to be 30
feet long and is famous for its aggressive hunting
pods.
(A) include the animal known as the killer whale,
which can grow to be 30 feet long and is
(B) include the animal known as the killer whale,
growing as big as 30 feet long and
(C) include the animal known as the killer whale,
growing up to 30 feet long and being
(D) includes the animal known as the killer whale,
which can grow as big as 30 feet long and is
(E) includes the animal known as the killer whale,
which can grow to be 30 feet long and it is
754. The rst trenches that were cut into a 500‐acre site
at Tell Hamoukar, Syria, have yielded strong evidence
for centrally administered complex societies in
northern regions of the Middle East that were arising
simultaneously with but independently of the more
celebrated city‐states of southern Mesopotamia, in
what is now southern Iraq.
(A) that were cut into a 500‐acre site at Tell
Hamoukar, Syria, have yielded strong evidence
for centrally administered complex societies in
northern regions of the Middle East that were
arising simultaneously with but
(B) that were cut into a 500‐acre site at Tell
Hamoukar, Syria, yields strong evidence that
centrally administered complex societies in
northern regions of the Middle East were arising
simultaneously with but also
(C) having been cut into a 500‐acre site at Tell
Hamoukar, Syria, have yielded strong evidence
that centrally administered complex societies in
northern regions of the Middle East were arising
simultaneously but
(D) cut into a 500‐acre site at Tell Hamoukar, Syria,
yields strong evidence of centrally administered
complex societies in northern regions of the
Middle East arising simultaneously but also
(E) cut into a 500‐acre site at Tell Hamoukar, Syria,
have yielded strong evidence that centrally
administered complex societies in northern
regions of the Middle East arose simultaneously
with but
9.6 Sentence Correction Practice Questions
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755. Companies are relying more and more on networked
computers for such critical tasks as inventory
management, electronic funds transfer, and electronic
data interchange, in which standard business
transactions are handled via computer rather than on
paper.
(A) in which standard business transactions are
handled via computer rather than on paper
(B) where computers handle standard business
transactions rather than on paper
(C) in which computers handle standard business
transactions instead of on paper
(D) where standard business transactions are
handled, not with paper, but instead via
computer
(E) in which standard business transactions are being
handled via computer, in place of on paper
756. Combining enormous physical strength with higher
intelligence, the Neanderthals appear as equipped for
facing any obstacle the environment could put in their
path, but their relatively sudden disappearance during
the Paleolithic era indicates that an inability to adapt to
some environmental change led to their extinction.
(A) appear as equipped for facing any obstacle the
environment could put in their path,
(B) appear to have been equipped to face any
obstacle the environment could put in their path,
(C) appear as equipped to face any obstacle the
environment could put in their paths,
(D) appeared as equipped to face any obstacle the
environment could put in their paths,
(E) appeared to have been equipped for facing any
obstacle the environment could put in their path,
757. To map Earth’s interior, geologists use a network of
seismometers to chart seismic waves that originate
in the earth’s crust and ricochet around its interior,
most rapidly traveling through cold, dense regions and
slower through hotter rocks.
(A) interior, most rapidly traveling through cold,
dense regions and slower
(B) interior, which travel most rapidly through cold,
dense regions, and more slowly
(C) interior, traveling most rapidly through cold,
dense regions and more slowly
(D) interior and most rapidly travel through cold,
dense regions, and slower
(E) interior and that travel most rapidly through cold,
dense regions and slower
758. Prices at the producer level are only 1.3 percent
higher now than a year ago and are going down,
even though oods in the Midwest and drought in the
South are hurting crops and therefore raised corn and
soybean prices.
(A) than a year ago and are going down, even
though oods in the Midwest and drought in the
South are hurting crops and therefore raised
(B) than those of a year ago and are going down,
even though oods in the Midwest and drought in
the South are hurting crops and therefore raising
(C) than a year ago and are going down, despite
oods in the Midwest and drought in the South,
and are hurting crops and therefore raising
(D) as those of a year ago and are going down, even
though oods in the Midwest and drought in the
South hurt crops and therefore raise
(E) as they were a year ago and are going down,
despite oods in the Midwest and drought in
the South, and are hurting crops and therefore
raising
759. Fossils of the arm of a sloth found in Puerto Rico in
1991, and dated at 34 million years old, made it the
earliest known mammal of the Greater Antilles Islands.
(A) sloth found in Puerto Rico in 1991, and dated at
34 million years old, made it the earliest known
mammal of
(B) sloth, that they found in Puerto Rico in 1991, has
been dated at 34 million years old, thus making
it the earliest mammal known on
(C) sloth that was found in Puerto Rico in 1991, was
dated at 34 million years old, making this the
earliest known mammal of
(D) sloth, found in Puerto Rico in 1991, have been
dated at 34 million years old, making the sloth
the earliest known mammal on
(E) sloth which, found in Puerto Rico in 1991, was
dated at 34 million years old, made the sloth the
earliest known mammal of
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760. Recently physicians have determined that stomach
ulcers are not caused by stress, alcohol, or rich foods,
but a bacterium that dwells in the mucous lining of the
stomach.
(A) not caused by stress, alcohol, or rich foods, but
(B) not caused by stress, alcohol, or rich foods, but
are by
(C) caused not by stress, alcohol, or rich foods, but
by
(D) caused not by stress, alcohol, and rich foods, but
(E) caused not by stress, alcohol, and rich foods,
but are by
761. The eyes of the elephant seal adapt to darkness more
quickly than any other animal yet tested, thus allowing
it to hunt ef ciently under the gloomy conditions at its
feeding depth of between 300 and 700 meters.
(A) The eyes of the elephant seal adapt to darkness
more quickly than any other animal yet tested,
thus allowing it
(B) The eyes of the elephant seal adapt to darkness
more quickly than does any other animal yet
tested, allowing them
(C) The eyes of the elephant seal adapt to darkness
more quickly than do those of any other animal
yet tested, allowing it
(D) Because they adapt to darkness more quickly
than any other animal yet tested, the eyes of the
elephant seal allow it
(E) Because the eyes of the elephant seal adapt
to darkness more quickly than do those of any
other animal yet tested, it allows them
762. A mutual fund having billions of dollars in assets will
typically invest that money in hundreds of companies,
rarely holding more than one percent of the shares of
any particular corporation.
(A) companies, rarely holding more than one percent
(B) companies, and it is rare to hold at least one
percent or more
(C) companies and rarely do they hold more than
one percent
(D) companies, so that they rarely hold more than
one percent
(E) companies; rarely do they hold one percent or
more
763. Positing an enormous volcanic explosion at the end
of the Permian period would explain the presence of a
buried crater, account for the presence of the element
iridium (originating deep within the earth), and the
presence of quartz having been shattered by high-
impact shock waves.
(A) account for the presence of the element iridium
(originating deep within the earth), and the
presence of quartz having been
(B) of the element iridium (originating deep within the
earth), and of quartz
(C) the element iridium (originating deep within the
earth), and explain the presence of quartz having
been
(D) the presence of the element iridium (originating
deep within the earth), and explain the presence
of quartz
(E) explain the element iridium (originating deep
within the earth), and the presence of quartz
764. The 19‐year‐old pianist and composer performed his
most recent work all over Europe, Asia, and North
America last year, winning prestigious awards in both
London as well as Tokyo for his achievement at so
young an age, and he is hoping to continue composing
now that he has returned to Chicago.
(A) winning prestigious awards in both London as
well as Tokyo for his achievement at so young an
age, and he is hoping
(B) winning prestigious awards both in London and
Tokyo for his achievement at such a young age,
and hoping
(C) having won prestigious awards both in London
and Tokyo for his achievement at so young an
age, hoping
(D) winning prestigious awards in both London and
Tokyo for his achievement at such a young age,
and he hopes
(E) having won prestigious awards both in London as
well as Tokyo for his achievement at so young an
age, and he hopes
9.6 Sentence Correction Practice Questions
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765. Star sh, with anywhere from ve to eight arms,
have a strong regenerative ability, and if one arm is
lost it quickly replaces it, sometimes by the animal
overcompensating and growing an extra one or two.
(A) one arm is lost it quickly replaces it, sometimes
by the animal overcompensating and
(B) one arm is lost it is quickly replaced, with the
animal sometimes overcompensating and
(C) they lose one arm they quickly replace it,
sometimes by the animal overcompensating,
(D) they lose one arm they are quickly replaced, with
the animal sometimes overcompensating,
(E) they lose one arm it is quickly replaced,
sometimes with the animal overcompensating,
766. In 2000, a mere two dozen products accounted for
half the increase in spending on prescription drugs,
a phenomenon that is explained not just because of
more expensive drugs but by the fact that doctors are
writing many more prescriptions for higher‐cost drugs.
(A) a phenomenon that is explained not just because
of more expensive drugs but by the fact that
doctors are writing
(B) a phenomenon that is explained not just by the
fact that drugs are becoming more expensive
but also by the fact that doctors are writing
(C) a phenomenon occurring not just because of
drugs that are becoming more expensive but
because of doctors having also written
(D) which occurred not just because drugs are
becoming more expensive but doctors are also
writing
(E) which occurred not just because of more expensive
drugs but because doctors have also written
767. Similar to other early Mississippi Delta blues singers,
the music of Robert Johnson arose from an oral
tradition beginning with a mixture of chants, ddle
tunes, and religious music and only gradually evolved
into the blues.
(A) Similar to other early Mississippi Delta blues
singers, the music of Robert Johnson arose from
an oral tradition beginning with
(B) Similar to that of other early Mississippi Delta
blues singers, Robert Johnson made music that
arose from an oral tradition that began with
(C) As with other early Mississippi Delta blues
singers, Robert Johnson made music that arose
from an oral tradition beginning as
(D) Like other early Mississippi Delta blues singers,
Robert Johnson’s music arose from an oral
tradition beginning with
(E) Like the music of other early Mississippi Delta
blues singers, the music of Robert Johnson
arose from an oral tradition that began as
768. Thelonious Monk, who was a jazz pianist and
composer, produced a body of work both rooted in
the stride‐piano tradition of Willie (The Lion) Smith and
Duke Ellington, yet in many ways he stood apart from
the mainstream jazz repertory.
(A) Thelonious Monk, who was a jazz pianist and
composer, produced a body of work both rooted
(B) Thelonious Monk, the jazz pianist and composer,
produced a body of work that was rooted both
(C) Jazz pianist and composer Thelonious Monk,
who produced a body of work rooted
(D) Jazz pianist and composer Thelonious Monk
produced a body of work that was rooted
(E) Jazz pianist and composer Thelonious Monk
produced a body of work rooted both
769. Nobody knows exactly how many languages there
are in the world, partly because of the dif culty
of distinguishing between a language and the
sublanguages or dialects within it, but those who
have tried to count typically have found about ve
thousand.
(A) and the sublanguages or dialects within it, but
those who have tried to count typically have
found
(B) and the sublanguages or dialects within them,
with those who have tried counting typically
nding
(C) and the sublanguages or dialects within it, but
those who have tried counting it typically nd
(D) or the sublanguages or dialects within them, but
those who tried to count them typically found
(E) or the sublanguages or dialects within them, with
those who have tried to count typically nding
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770. Although a number of excellent studies narrate
the development of domestic technology and
its impact on housewifery, these works do not
discuss the contributions of the women employed
by manufacturers and utility companies as product
demonstrators and publicists, who initially promoted
new and unfamiliar technology to female consumers.
(A) by manufacturers and utility companies as
product demonstrators and publicists,
(B) to be product demonstrators and publicists by
manufacturers and utility companies,
(C) to demonstrate and publicize their products by
manufacturers and utility companies
(D) by manufacturers and utility companies to be
demonstrators and publicists of their products
(E) by manufacturers and utility companies to
demonstrate and publicize their products
771. The absence from business and nancial records of
the nineteenth century of statistics about women leave
us with no record of the jobs that were performed by
women and how they survived economically.
(A) from business and nancial records of the
nineteenth century of statistics about women
leave us with no record of the jobs that were
performed by women and
(B) from business and nancial records of statistics
about women from the nineteenth century leave us
with no record of what jobs women performed or
(C) of statistics for women from business and
nancial records in the nineteenth century leaves
us with no record of either the jobs that women
were performing and of
(D) of statistics on women from business and nancial
records in the nineteenth century leave us with no
record of the jobs that women performed or of
(E) of statistics about women from business and
nancial records of the nineteenth century leaves
us with no record of either what jobs women
performed or
772. Heating‐oil prices are expected to be higher this year
than last because re ners are paying about $5 a barrel
more for crude oil than they were last year.
(A) Heating‐oil prices are expected to be higher this
year than last because re ners are paying about
$5 a barrel more for crude oil than they were
(B) Heating‐oil prices are expected to rise higher this
year over last because re ners pay about $5 a
barrel for crude oil more than they did
(C) Expectations are for heating‐oil prices to be
higher this year than last year’s because re ners
are paying about $5 a barrel for crude oil more
than they did
(D) It is the expectation that heating‐oil prices will be
higher for this year over last because re ners
are paying about $5 a barrel more for crude oil
now than what they were
(E) It is expected that heating‐oil prices will rise higher
this year than last year’s because re ners pay
about $5 a barrel for crude oil more than they did
773. Even though Clovis points, spear points with
longitudinal grooves chipped onto their faces, have
been found all over North America, they are named for
the New Mexico site where they were rst discovered
in 1932.
(A) Even though Clovis points, spear points with
longitudinal grooves chipped onto their faces,
have been found all over North America, they are
named for the New Mexico site where they were
rst discovered in 1932.
(B) Although named for the New Mexico site where
rst discovered in 1932, Clovis points are spear
points of longitudinal grooves chipped onto
their faces and have been found all over North
America.
(C) Named for the New Mexico site where they have
been rst discovered in 1932, Clovis points,
spear points of longitudinal grooves chipped
onto the faces, have been found all over North
America.
(D) Spear points with longitudinal grooves that are
chipped onto the faces, Clovis points, even
though named for the New Mexico site where
rst discovered in 1932, but were found all over
North America.
(E) While Clovis points are spear points whose faces
have longitudinal grooves chipped into them,
they have been found all over North America,
and named for the New Mexico site where they
have been rst discovered in 1932.
9.6 Sentence Correction Practice Questions
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702
GMAT® Offi cial Guide 2018
774. Heavy commitment by an executive to a course of
action, especially if it has worked well in the past,
makes it likely to miss signs of incipient trouble or
misinterpret them when they do appear.
(A) Heavy commitment by an executive to a course
of action, especially if it has worked well in the
past, makes it likely to miss signs of incipient
trouble or misinterpret them when they do
appear.
(B) An executive who is heavily committed to a
course of action, especially one that worked well
in the past, makes missing signs of incipient
trouble or misinterpreting ones likely when they
do appear.
(C) An executive who is heavily committed to a
course of action is likely to miss or misinterpret
signs of incipient trouble when they do appear,
especially if it has worked well in the past.
(D) Executives’ being heavily committed to a course
of action, especially if it has worked well in the
past, makes them likely to miss signs of incipient
trouble or misinterpreting them when they do
appear.
(E) Being heavily committed to a course of action,
especially one that has worked well in the past,
is likely to make an executive miss signs of
incipient trouble or misinterpret them when they
do appear.
775. According to recent studies comparing the nutritional
value of meat from wild animals and meat from
domesticated animals, wild animals have less total fat
than do livestock fed on grain and more of a kind of fat
they think is good for cardiac health.
(A) wild animals have less total fat than do livestock
fed on grain and more of a kind of fat they think
is
(B) wild animals have less total fat than livestock fed
on grain and more of a kind of fat thought to be
(C) wild animals have less total fat than that of
livestock fed on grain and have more fat of a
kind thought to be
(D) total fat of wild animals is less than livestock
fed on grain and they have more fat of a kind
thought to be
(E) total fat is less in wild animals than that of
livestock fed on grain and more of their fat is of
a kind they think is
776. Yellow jackets number among the 900 or so species
of the world’s social wasps, wasps living in a highly
cooperative and organized society where they consist
almost entirely of females—the queen and her sterile
female workers.
(A) wasps living in a highly cooperative and
organized society where they consist almost
entirely of
(B) wasps that live in a highly cooperative and
organized society consisting almost entirely of
(C) which means they live in a highly cooperative and
organized society, almost all
(D) which means that their society is highly
cooperative, organized, and it is almost entirely
(E) living in a society that is highly cooperative,
organized, and it consists of almost all
777. Before 1988, insurance companies in California were
free to charge whatever rates the market would bear,
needing no approval from regulators before raising
rates.
(A) needing no approval from regulators before
raising
(B) and it needed no approval by regulators before
raising
(C) and needing no approval from regulators before
they raised
(D) with approval not needed by regulators before
they raised
(E) with no approval needed from regulators before
the raising of
778. Marconi’s conception of the radio was as a substitute
for the telephone, a tool for private conversation;
instead, it is precisely the opposite, a tool for
communicating with a large, public audience.
(A) Marconi’s conception of the radio was as a
substitute for the telephone, a tool for private
conversation; instead, it is
(B) Marconi conceived of the radio as a substitute
for the telephone, a tool for private conversation,
but which is
(C) Marconi conceived of the radio as a tool for
private conversation that could substitute for the
telephone; instead, it has become
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703
(D) Marconi conceived of the radio to be a tool
for private conversation, a substitute for the
telephone, which has become
(E) Marconi conceived of the radio to be a substitute
for the telephone, a tool for private conversation,
other than what it is,
779. Because there are provisions of the new maritime code
that provide that even tiny islets can be the basis for
claims to the sheries and oil elds of large sea areas,
they have already stimulated international disputes
over uninhabited islands.
(A) Because there are provisions of the new
maritime code that provide that even tiny islets
can be the basis for claims to the sheries and
oil elds of large sea areas, they have already
stimulated
(B) Because the new maritime code provides that
even tiny islets can be the basis for claims to the
sheries and oil elds of large sea areas, it has
already stimulated
(C) Even tiny islets can be the basis for claims to the
sheries and oil elds of large sea areas under
provisions of the new maritime code, already
stimulating
(D) Because even tiny islets can be the basis for
claims to the sheries and oil elds of large
sea areas under provisions of the new maritime
code, this has already stimulated
(E) Because even tiny islets can be the basis for
claims to the sheries and oil elds of large
sea areas under provisions of the new maritime
code, which is already stimulating
780. Unlike the automobile company, whose research was
based on crashes involving sport utility vehicles, the
research conducted by the insurance company took
into account such factors as a driver’s age, sex, and
previous driving record.
(A) company, whose research was based on
(B) company, which researched
(C) company, in its research of
(D) company’s research, having been based on
(E) company’s research on
781. Gusty westerly winds will continue to usher in a
seasonably cool air mass into the region, as a broad
area of high pressure will build and bring fair and dry
weather for several days.
(A) to usher in a seasonably cool air mass into the
region, as a broad area of high pressure will
build and
(B) ushering in a seasonably cool air mass into the
region and a broad area of high pressure will
build that
(C) to usher in a seasonably cool air mass to the
region, a broad area of high pressure building,
and
(D) ushering a seasonably cool air mass in the
region, with a broad area of high pressure
building and
(E) to usher a seasonably cool air mass into the
region while a broad area of high pressure
builds, which will
782. With the patience of its customers and with its network
strained to the breaking point, the on-line service
company announced a series of new initiatives trying
to relieve the congestion that has led to at least four
class-action lawsuits and thousands of complaints from
frustrated customers.
(A) the patience of its customers and with its
network strained to the breaking point, the on-
line service company announced a series of new
initiatives trying to relieve
(B) the patience of its customers and its network
strained to the breaking point, the on-line service
company announced a series of new initiatives
that try to relieve
(C) its network and the patience of its customers
strained to the breaking point, the on-line service
company announced a series of new initiatives to
try to relieve
(D) its network and with the patience of its
customers strained to the breaking point, the
on-line service company announced a series of
initiatives to try relieving
(E) its network and its customers’ patience strained
to the breaking point, the on-line service
company announced a series of new initiatives to
try relieving
9.6 Sentence Correction Practice Questions
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704
GMAT® Offi cial Guide 2018
783. November is traditionally the strongest month for sales
of light trucks, but sales this past November, even when
compared with sales in previous Novembers, accounted
for a remarkably large share of total vehicle sales.
(A) but sales this past November, even when
compared with sales in previous Novembers,
(B) but even when it is compared with previous
Novembers, this past November’s sales
(C) but even when they are compared with previous
Novembers, sales of light trucks this past
November
(D) so that compared with previous Novembers,
sales of light trucks this past November
(E) so that this past November’s sales, even
compared with previous Novembers’ sales,
784. Most of the country’s biggest daily newspapers had
lower circulation in the six months from October 1995
through March 1996 than a similar period a year earlier.
(A) a similar period
(B) a similar period’s
(C) in a similar period
(D) that in a similar period
(E) that of a similar period
785. Mauritius was a British colony for almost 200 years,
excepting for the domains of administration and
teaching, the English language was never really spoken
on the island.
(A) excepting for
(B) except in
(C) but except in
(D) but excepting for
(E) with the exception of
786. Although appearing less appetizing than most of
their round and red supermarket cousins, heirloom
tomatoes, grown from seeds saved during the previous
year—they are often green and striped, or have plenty
of bumps and bruises—heirlooms are more avorful
and thus in increasing demand.
(A) Although appearing less appetizing than most
of their round and red supermarket cousins,
heirloom tomatoes, grown from seeds saved
during the previous year
(B) Although heirloom tomatoes, grown from seeds
saved during the previous year, appear less
appetizing than most of their round and red
supermarket cousins
(C) Although they appear less appetizing than most
of their round and red supermarket cousins,
heirloom tomatoes, grown from seeds saved
during the previous year
(D) Grown from seeds saved during the previous
year, heirloom tomatoes appear less appetizing
than most of their round and red supermarket
cousins
(E) Heirloom tomatoes, grown from seeds saved
during the previous year, although they appear
less appetizing than most of their round and red
supermarket cousins
787. The World Wildlife Fund has declared that global
warming, a phenomenon most scientists agree to be
caused by human beings in burning fossil fuels, will
create havoc among migratory birds by altering the
environment in ways harmful to their habitats.
(A) a phenomenon most scientists agree to be
caused by human beings in burning fossil fuels,
(B) a phenomenon most scientists agree that is
caused by fossil fuels burned by human beings,
(C) a phenomenon that most scientists agree is
caused by human beings’ burning of fossil fuels,
(D) which most scientists agree on as a
phenomenon caused by human beings who burn
fossil fuels,
(E) which most scientists agree to be a phenomenon
caused by fossil fuels burned by human beings,
788. The largest of all the planets, not only is Jupiter three
times so massive as Saturn, the next larger planet, but
also possesses four of the largest satellites, or moons,
in our solar system.
(A) not only is Jupiter three times so massive as
Saturn, the next larger
(B) not only is Jupiter three times as massive as
Saturn, the next largest
(C) Jupiter, not only three times as massive as
Saturn, the next largest
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705
(D) Jupiter not only is three times as massive as
Saturn, the next largest
(E) Jupiter is not only three times so massive as
Saturn, the next larger
789. While many of the dinosaur fossils found recently
in northeast China seem to provide evidence of the
kinship between dinosaurs and birds, the wealth of
enigmatic fossils seem more likely at this stage that
they will in ame debates over the origin of birds rather
than settle them.
(A) seem more likely at this stage that they will in ame
debates over the origin of birds rather than
(B) seem more likely that it will in ame debates over
the origin of birds at this stage than
(C) seems more likely to in ame debates on the
origin of birds at this stage rather than
(D) seems more likely at this stage to in ame
debates over the origin of birds than to
(E) seems more likely that it will in ame debates on
the origin of birds at this stage than to
790. Found only in the Western Hemisphere and surviving
through extremes of climate, hummingbirds’ range
extends from Alaska to Tierra del Fuego, from sea‐level
rain forests to the edges of Andean snow elds and ice
elds at altitudes of 15,000 feet.
(A) Found only in the Western Hemisphere
and surviving through extremes of climate,
hummingbirds’ range extends
(B) Found only in the Western Hemisphere,
hummingbirds survive through extremes of
climate, their range extending
(C) Hummingbirds, found only in the Western
Hemisphere and surviving through extremes of
climate, with their range extending
(D) Hummingbirds, found only in the Western
Hemisphere and surviving through extremes of
climate, their range extends
(E) Hummingbirds are found only in the Western
Hemisphere, survive through extremes of
climate, and their range extends
791. She was less successful after she had emigrated
to New York compared to her native Germany,
photographer Lotte Jacobi nevertheless earned a small
group of discerning admirers, and her photographs
were eventually exhibited in prestigious galleries
across the United States.
(A) She was less successful after she had emigrated
to New York compared to
(B) Being less successful after she had emigrated to
New York as compared to
(C) Less successful after she emigrated to New York
than she had been in
(D) Although she was less successful after
emigrating to New York when compared to
(E) She had been less successful after emigrating to
New York than in
792. Scientists have recently found evidence that black
holes—regions of space in which matter is so
concentrated and the pull of gravity so powerful that
nothing, not even light, can emerge from them—probably
exist at the core of nearly all galaxies and the mass of
each black hole is proportional to its host galaxy.
(A) exist at the core of nearly all galaxies and the
mass of each black hole is proportional to
(B) exist at the core of nearly all galaxies and that the
mass of each black hole is proportional to that of
(C) exist at the core of nearly all galaxies, and that
the mass of each black hole is proportional to
(D) exists at the core of nearly all galaxies, and that the
mass of each black hole is proportional to that of
(E) exists at the core of nearly all galaxies and the
mass of each black hole is proportional to that of
793. The use of lie detectors is based on the assumption that
lying produces emotional reactions in an individual that,
in turn, create unconscious physiological responses.
(A) that, in turn, create unconscious physiological
responses
(B) that creates unconscious physiological
responses in turn
(C) creating, in turn, unconscious physiological
responses
(D) to create, in turn, physiological responses that
are unconscious
(E) who creates unconscious physiological
responses in turn
9.6 Sentence Correction Practice Questions
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706
GMAT® Offi cial Guide 2018
794. Australian embryologists have found evidence that
suggests that the elephant is descended from an
aquatic animal, and its trunk originally evolving as a
kind of snorkel.
(A) that suggests that the elephant is descended from
an aquatic animal, and its trunk originally evolving
(B) that has suggested the elephant descended from
an aquatic animal, its trunk originally evolving
(C) suggesting that the elephant had descended from
an aquatic animal with its trunk originally evolved
(D) to suggest that the elephant had descended
from an aquatic animal and its trunk originally
evolved
(E) to suggest that the elephant is descended from an
aquatic animal and that its trunk originally evolved
795. Most efforts to combat such mosquito‐borne diseases
like malaria and dengue have focused either on the
vaccination of humans or on exterminating mosquitoes
with pesticides.
(A) like malaria and dengue have focused either on
the vaccination of humans or on exterminating
(B) like malaria and dengue have focused either on
vaccinating of humans or on the extermination of
(C) as malaria and dengue have focused on either
vaccinating humans or on exterminating
(D) as malaria and dengue have focused on either
vaccinating of humans or on extermination of
(E) as malaria and dengue have focused on either
vaccinating humans or exterminating
796. Among the Tsonga, a Bantu-speaking group of tribes
in southeastern Africa, dance teams represent
their own chief at the court of each other, providing
entertainment in return for food, drink, and lodging.
(A) the court of each other, providing entertainment
in return for
(B) the court of another and provide entertainment in
return for
(C) the court of the other, so as to provide
entertainment as a return on
(D) each other’s court, entertainment being provided
in return for
(E) another’s court and provide entertainment as a
return on
797. Almost like clones in their similarity to one another, the
cheetah species’ homogeneity makes them especially
vulnerable to disease.
(A) the cheetah species’ homogeneity makes them
especially vulnerable to disease
(B) the cheetah species is especially vulnerable to
disease because of its homogeneity
(C) the homogeneity of the cheetah species makes it
especially vulnerable to disease
(D) homogeneity makes members of the cheetah
species especially vulnerable to disease
(E) members of the cheetah species are especially
vulnerable to disease because of their
homogeneity
798. As sources of electrical power, windmills now account
for only about 2,500 megawatts nationwide, but
production is almost expected to double by the end
of the year, which would provide enough electricity for
1.3 million households.
(A) almost expected to double by the end of the
year, which would provide
(B) almost expected that it will double by the end of
the year, thus providing
(C) expected that it will almost double by the end of
the year to provide
(D) expected almost to double by the end of the
year and thus to provide
(E) expected almost to double by the end of the
year, which would thus be providing
799. While most of the earliest known ball courts in
Mesoamerica date to 900–400 B.C., waterlogged
latex balls found at El Manati and representations of
ballplayers painted on ceramics found at San Lorenzo
attest to the fact that the Mesoamerican ballgame was
well established by the mid-thirteenth century B.C.
(A) waterlogged latex balls found at El Manati
and representations of ballplayers painted on
ceramics found at San Lorenzo attest
(B) waterlogged latex balls found at El Manati and
the painting of representations of ballplayers on
ceramics found at San Lorenzo attests
(C) waterlogged latex balls found at El Manati
and ceramics painted with representations of
ballplayers found at San Lorenzo attests
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707
(D) the nding of waterlogged latex balls at El Manati
and the painting of representations of ballplayers
on ceramics found at San Lorenzo attests
(E) the nding of waterlogged latex balls at El Manati
and of representations of ballplayers painted on
ceramics at San Lorenzo attest
800. As criminal activity on the Internet becomes more and
more sophisticated, not only are thieves able to divert
cash from company bank accounts, they can also pilfer
valuable information such as business development
strategies, new product speci cations, and contract
bidding plans, and sell the data to competitors.
(A) they can also pilfer valuable information such as
business development strategies, new product
speci cations, and contract bidding plans, and
sell
(B) they can also pilfer valuable information that
includes business development strategies, new
product speci cations, and contract bidding
plans, and selling
(C) also pilfering valuable information including
business development strategies, new product
speci cations, and contract bidding plans, selling
(D) but also pilfer valuable information such as
business development strategies, new product
speci cations, and contract bidding plans to sell
(E) but also pilfering valuable information such as
business development strategies, new product
speci cations, and contract bidding plans and
selling
801. Last week local shrimpers held a news conference to
take some credit for the resurgence of the rare Kemp’s
ridley turtle, saying that their compliance with laws
requiring that turtle‐excluder devices be on shrimp nets
protect adult sea turtles.
(A) requiring that turtle‐excluder devices be on
shrimp nets protect
(B) requiring turtle‐excluder devices on shrimp nets
is protecting
(C) that require turtle‐excluder devices on shrimp
nets protect
(D) to require turtle‐excluder devices on shrimp nets
are protecting
(E) to require turtle‐excluder devices on shrimp nets
is protecting
802. A ruined structure found at Aqaba, Jordan, was
probably a church, as indicated in its eastward
orientation and by its overall plan, as well as artifacts,
such as glass oil‐lamp fragments, found at the site.
(A) A ruined structure found at Aqaba, Jordan, was
probably a church, as indicated in its eastward
orientation and by its overall plan, as well as
(B) A ruined structure found at Aqaba, Jordan, once
probably being a church, was indicated by its
eastward orientation, overall plan, and
(C) Indicating that a ruined structure found at Aqaba,
Jordan, was probably a church were its eastward
orientation and overall plan, but also the
(D) A ruined structure found at Aqaba, Jordan, was
probably a church, as indicates its eastward
orientation and overall plan, as well as the
(E) That a ruined structure found at Aqaba, Jordan,
was probably a church is indicated by its
eastward orientation and overall plan, as well as
by the
803. In the major cities of industrialized countries at the
end of the nineteenth century, important public places
such as theaters, restaurants, shops, and banks had
installed electric lighting, but electricity was in less
than 1 percent of homes, where lighting was still
provided mainly by candles or gas.
(A) electricity was in less than 1 percent of homes,
where lighting was still
(B) electricity was in less than 1 percent of homes
and lighting still
(C) there had been less than 1 percent of homes
with electricity, where lighting was still being
(D) there was less than 1 percent of homes that had
electricity, having lighting that was still
(E) less than 1 percent of homes had electricity,
where lighting had still been
9.6 Sentence Correction Practice Questions
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708
GMAT® Offi cial Guide 2018
804. By 1999, astronomers had discovered 17 nearby stars
that are orbited by planets about the size of Jupiter.
(A) had discovered 17 nearby stars that are orbited
by planets
(B) had discovered 17 nearby stars with planets
orbiting them that were
(C) had discovered that there were 17 nearby stars
that were orbited by planets
(D) have discovered 17 nearby stars with planets
orbiting them that are
(E) have discovered that 17 nearby stars are orbited
by planets
805. Although she was considered among her
contemporaries to be the better poet than her
husband, later Elizabeth Barrett Browning was
overshadowed by his success.
(A) Although she was considered among her
contemporaries to be the better poet than her
husband, later Elizabeth Barrett Browning was
overshadowed by his success.
(B) Although Elizabeth Barrett Browning was
considered among her contemporaries as a
better poet than her husband, she was later
overshadowed by his success.
(C) Later overshadowed by the success of her
husband, Elizabeth Barrett Browning’s poetry had
been considered among her contemporaries to
be better than that of her husband.
(D) Although Elizabeth Barrett Browning’s success
was later overshadowed by that of her husband,
among her contemporaries she was considered
the better poet.
(E) Elizabeth Barrett Browning’s poetry was
considered among her contemporaries as better
than her husband, but her success was later
overshadowed by his.
806. In no other historical sighting did Halley’s Comet
causesuch a worldwide sensation as did its return in
1910–1911.
(A) did its return in 1910–1911
(B) had its 1910–1911 return
(C) in its return of 1910–1911
(D) its return of 1910–1911 did
(E) its return in 1910–1911
807. Rock samples taken from the remains of an asteroid
about twice the size of the 6‐mile‐wide asteroid that
eradicated the dinosaurs has been dated to be 3.47
billion years old and thus is evidence of the earliest
known asteroid impact on Earth.
(A) has been dated to be 3.47 billion years old and
thus is
(B) has been dated at 3.47 billion years old and thus
(C) have been dated to be 3.47 billion years old and
thus are
(D) have been dated as being 3.47 billion years old
and thus
(E) have been dated at 3.47 billion years old and
thus are
709
668. E
669. D
670. B
671. C
672. B
673. C
674. D
675. D
676. D
677. E
678. B
679. B
680. D
681. C
682. D
683. B
684. A
685. D
686. E
687. C
688. B
689. C
690. D
691. E
692. B
693. C
694. A
695. C
696. E
697. B
698. E
699. C
700. D
701. A
702. A
703. B
704. E
705. C
706. B
707. D
708. E
709. E
710. D
711. A
712. B
713. E
714. D
715. E
716. C
717. D
718. D
719. C
720. A
721. C
722. B
723. D
724. E
725. E
726. D
727. D
728. C
729. C
730. E
731. D
732. E
733. B
734. B
735. E
736. A
737. B
738. B
739. A
740. E
741. B
742. A
743. A
744. E
745. C
746. E
747. A
748. A
749. D
750. B
751. B
752. B
753. A
754. E
755. A
756. B
757. C
758. B
759. D
760. C
761. C
762. A
763. B
764. D
765. B
766. B
767. E
768. D
769. A
770. A
771. E
772. A
773. A
774. E
775. B
776. B
777. A
778. C
779. B
780. E
781. E
782. C
783. A
784. C
785. C
786. B
787. C
788. D
789. D
790. B
791. C
792. B
793. A
794. E
795. E
796. B
797. E
798. D
799. A
800. A
801. B
802. E
803. A
804. A
805. D
806. C
807. E
9.7 Answer Key
9.7 Sentence Correction Answer Key
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GMAT® Offi cial Guide 2018
668. In a review of 2,000 studies of human behavior that
date back to the 1940s, two Swiss psychologists,
declaring that since most of the studies had failed to
control for such variables as social class and family
size, none could be taken seriously.
(A) psychologists, declaring that since most of the
studies had failed to control for such variables as
social class and family size,
(B) psychologists, declaring that most of the studies
failed in not controlling for such variables like
social class and family size, and
(C) psychologists declared that since most of
the studies, having failed to control for such
variables as social class and family size,
(D) psychologists declared that since most of the
studies fail in controlling for such variables like
social class and family size,
(E) psychologists declared that since most of the
studies had failed to control for variables such as
social class and family size,
Verb form; Diction
e subject of the sentence, two Swiss
psychologists, needs a main verb. e ‐ ing verb
form declaring cannot, on its own, be the main
verb of a correct English sentence. Furthermore,
the clause that addresses the reason for not taking
the studies also seriously needs a subject ( most of
the studies ) and a verb ( had failed ).
A e sentence needs a verb form that agrees
in person and number with the subject
two Swiss psychologists and that is in the
appropriate tense.
B In addition to the problem with declaring ,
explained above, in this version of the
sentence the phrase failed in not controlling
for is awkward and does not mean the
same thing as failed to control for . Also,
the expression such X like Y is incorrect in
English; the correct usage is such X as Y .
C e correct form for the sentence’s main
verb declared is used here, but having failed is
a participial form and as such cannot be the
main verb in the clause.
D English has a rule of sequence of tenses:
once a verb form is marked for past tense,
the following verb forms that describe
the same object or event have to be in the
past tense as well. us, fail is the wrong
verb form. e expression such X like Y is
incorrect in English; the correct usage is
such X as Y .
E Correct. e subject two Swiss psychologists
is followed by a verb in the past tense
( declared ); the dependent clause since …
family size also has the correct verb form
( had failed ).
e correct answer is E.
669. In her presentation, the head of the Better Business
Bureau emphasized that companies should think of the
cost of conventions and other similar gatherings as not
an expense, but as an investment in networking that
will pay dividends.
(A) as not an expense, but as
(B) as not expense but
(C) not an expense, rather
(D) not as an expense, but as
(E) not in terms of expense, but
Parallelism; Idiom
is sentence is constructed around not as X,
but as Y , which must start with the word not
in accordance with this idiomatic pattern, and
express both parts in a parallel way.
A is sentence improperly places as before not .
B is sentence improperly places as before not .
9.8 Answer Explanations
The following discussion of sentence correction is intended to familiarize you with the most efficient
and effective approaches to these kinds of questions. The particular questions in this chapter are
generally representative of the kinds of sentence correction questions you will encounter on the
GMAT exam.
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C is version lacks the required words as and
but .
D Correct. e idiom has all of its parts and
expresses the two opposed concepts in
parallel terms.
E Although in terms of is an acceptable
substitute for as, the construction is no
longer parallel due to the lack of a second in
terms of (or as ) after but .
e correct answer is D.
670. Recent interdisciplinary studies advance the argument
that emotions, including those deemed personal
or private is a social phenomenon, though one
inseparable from bodily response.
(A) private is a social phenomenon, though one
inseparable
(B) private, are social phenomena that are
inseparable
(C) private are a social phenomenon but are not
those separable
(D) private—are social phenomena but not separable
(E) also as private emotions, are social phenomena
not inseparable
Agreement; Rhetorical construction
e main problem is one of agreement: in the
subordinate clause starting with that , the subject
is the plural emotions , which demands the verb
are , not is . Also, the phrase starting with including
is a parenthetical expression that needs to be
set o from the rest of the clause, with some
punctuation to indicate a pause at its end (after
private ).
A e verb form is is incorrect, and should
instead be are ; the parenthetical expression
is not separated at its end from the rest of
the clause.
B Correct. Are is the correct agreeing verb
form, and the comma after private correctly
sets o the parenthetical expression.
C Are is correct, but nothing after private sets
o the parenthetical expression from the
subsequent material. In addition, not those
separable is awkwardly phrased; it would be
better as not separable or inseparable as in the
correct answer choice B.
D e dash would be correct to set o the
parenthetical expression only if including
had been immediately preceded by a dash;
otherwise a comma is needed. e phrase
not separable is awkward; it would be better
as are not separable or are inseparable.
E e phrase also as private emotions is
wordy and unidiomatic. e phrase social
phenomena not inseparable not only does
not express the intended meaning, but is
also awkward without a verb and a relative
pronoun such as that : a better phrasing is
social phenomena that are not separable .
e correct answer is B.
671. Manufacturers rate batteries in watt‐hours; if they rate
the watt‐hour higher, the longer the battery can be
expected to last.
(A) if they rate the watt‐hour higher, the longer
(B) rating the watt‐hour higher, it is that much longer
(C) the higher the watt‐hour rating, the longer
(D) the higher the watt‐hour rating, it is that much
longer that
(E) when the watt‐hour rating is higher, the longer it is
Logical predication; Grammatical
construction; Parallelism
ere is a cause‐and‐e ect connection between
the watt‐hour rating and the battery life; therefore,
the phrases describing the cause and e ect have
to be expressed in two parallel grammatical
constructions using the two comparative forms of
the modi ers higher and longer .
A Because of the way this version is
constructed, the pronoun they, referring to
manufacturers, illogically suggests that the
manufacturers can make the batteries last
longer simply by rating them higher. e
cause and e ect is also unparallel.
B Rating the watt‐hour higher needs a subject;
this faulty construction is known as a
dangling modi er. It is possible to construe
it as referring to manufacturers, which would
be confusing. See explanation of (A) above.
C Correct. is version uses the correct logical
and grammatical structure the higher X, …
the longer Y .
9.8 Sentence Correction Answer Explanations
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D is version is unparallel and
ungrammatical. e correct form is the
higher X, the longer Y.
E is version is unparallel and
ungrammatical. e correct form is the
higher X, the longer Y .
e correct answer is C.
672. At the end of the 1930s, Duke Ellington was looking for
a composer to assist him—someone not only who could
arrange music for his successful big band, but mirroring
his eccentric writing style as well in order to nish the
many pieces he had started but never completed.
(A) someone not only who could arrange music
for his successful big band, but mirroring his
eccentric writing style as well in order to nish
(B) someone who could not only arrange music
for his successful big band, but also mirror his
eccentric writing style in order to nish
(C) someone who not only could arrange music for
his successful big band, but also to mirror his
eccentric writing style in nishing
(D) that being someone who could not only arrange
music for his successful big band, but mirroring
his eccentric writing style for nishing
(E) being someone not only who could arrange
music for his successful big band, but mirror his
eccentric writing style as well, nishing
Rhetorical construction; Parallelism
In describing the qualities Duke Ellington sought
in a composer, the sentence uses the construction
not only … but also.… In this construction the
clauses need to be parallel—for example, not only
subject verb, but also subject verb .
A is version is wordy, awkward, and
unparallel. Furthermore, the two verbs in
the not only … but also… construction have
to be in the same form, while here we have
arrange and mirroring .
B Correct. is version exempli es a truly
parallel construction. Here, not only and
but also are directly in front of the verbs
they introduce. e verbs denoting the two
qualities in the sought‐after composer are
the same form: arrange, mirror .
C is version is awkward and unparallel.
e two verbs have to be in the same
form, while here we have arrange and to
mirror. Finally, the best way to express the
causal relationship between the composer’s
qualities and nishing Ellington’s pieces is
to use the conjunction in order to.
D Instead of the shorter and clearer someone
who , this version uses the longer phrase that
being someone who , which is overly wordy.
Furthermore, the verbs are not in the same
form and so the construction is unparallel.
Finally, the best way to express the causal
relationship between the composer’s
qualities and nishing Ellington’s pieces is
to use the conjunction in order to.
E Placing being in front of someone is
potentially misleading; it could illogically
refer to Ellington himself. e not only …
but also … construction is also unparallel.
Finally, the best way to express the causal
relationship between this composer’s
qualities and nishing Ellington’s pieces is
to use the conjunction in order to.
e correct answer is B.
673. While Noble Sissle may be best known for his
collaboration with Eubie Blake, as both a vaudeville
performer and as a lyricist for songs and Broadway
musicals, also enjoying an independent career as a
singer with such groups as Hahn’s Jubilee Singers.
(A) and as a lyricist for songs and Broadway
musicals, also enjoying
(B) and writing lyrics for songs and Broadway
musicals, also enjoying
(C) and a lyricist for songs and Broadway musicals,
he also enjoyed
(D) as well as writing lyrics for songs and Broadway
musicals, he also enjoyed
(E) as well as a lyricist for songs and Broadway
musicals, he had also enjoyed
Grammatical construction; Idiom; Parallelism
As worded, this sentence opens with a dependent
clause (a clause that cannot stand on its own),
which requires a main clause (also known as an
independent clause) to complete the sentence;
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however, there is no main clause. Also, given the
placement of as before both , the as before a lyricist
is incorrect. It would be acceptable to write as both
a vaudeville performer and a lyricist or to write both
as a vaudeville performer and as a lyricist ; it is not
acceptable to mix the two forms, as is done here.
A e dependent clause, While . . . Broadway
musicals , is followed by a participial phrase
rather than a main clause and is therefore
ungrammatical. Furthermore, the word as
before a lyricist violates the parallel structure
required by the phrase both . . . and .
B e construction as both a performer and
writing lyrics is incorrect. Also, like (A), this
version of the sentence does not supply a
main clause.
C Correct. Unlike (A) and (B), this version
has a main clause. Also, unlike the other
version, it correctly uses the both x and
y form.
D Although this version does supply the main
clause anticipated by While . . ., its use as
both a vaudeville performer as well as writing
lyrics is incorrect.
E is version’s use of both x as well as y
instead of both x and y is incorrect. It also
introduces an inexplicable past perfect verb,
had . . . enjoyed , in the main clause.
e correct answer is C.
674. Air traf c routes over the North Pole are currently used
by only two or three planes a day, but it was found
by a joint Canadian–Russian study to be both feasible
as well as desirable if those routes are opened to
thousands more commercial planes a year.
(A) Air traf c routes over the North Pole are
currently used by only two or three planes a day,
but it was found by a joint Canadian–Russian
study to be both feasible as well as desirable
if those routes are opened to thousands more
commercial planes a year.
(B) Currently used by only two or three planes a day,
a joint Canadian–Russian study has found that if
air traf c routes over the North Pole are opened
to thousands more commercial planes a year, it
would be both feasible and desirable.
(C) A joint Canadian–Russian study, nding it to be
both feasible as well as desirable to open air
traf c routes over the North Pole, which are
currently used by only two or three planes a day,
to thousands more commercial planes a year.
(D) Although air traf c routes over the North Pole
are currently used by only two or three planes a
day, a joint Canadian–Russian study has found
that opening those routes to thousands more
commercial planes a year is both feasible and
desirable.
(E) With air traf c routes over the North Pole
currently used by only two or three planes a
day, opening those routes to thousands more
commercial planes a year has been found by a
joint Canadian—Russian study as both feasible
and desirable.
Rhetorical construction; Verb form; Logical
predication
e point of the sentence is to share the results
of a study about air routes over the North Pole,
but the wording is confusing and verbose. e
passive construction it was found by a joint
Canadian–Russian study to be could be expressed
more directly and clearly in active voice: a joint
Canadian–Russian study has found.
A e passive construction it was found by a
joint Canadian–Russian study to be, especially
followed by the conditional if, is wordy,
awkward, and unclear.
B Used by only two or three planes illogically
modi es a joint Canadian–Russian study; the
pronoun it has no clear antecedent.
C e subject A joint Canadian–Russian study
has no verb; to thousands more commercial
planes is located too far away from to open,
which it is intended to modify.
D Correct. e sentence uses correctly placed
modi ers and the active voice to explain
clearly what a joint Canadian–Russian study
has found.
E e passive construction opening those routes
... has been found by a joint Canadian–
Russian study as both is wordy and
unidiomatic.
e correct answer is D.
9.8 Sentence Correction Answer Explanations
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675. From an experiment using special extrasensory
perception cards, each bearing one of a set of
symbols, parapsychologist Joseph Banks Rhine claimed
statistical proof for subjects who could use thought
transference to identify a card in the dealer’s hand.
(A) for subjects who could use thought transference
to identify a card in the dealer’s hand
(B) for a card in the dealer’s hand to be identi ed by
subjects with thought transference
(C) of subjects able to identify with thought
transference a card in the dealer’s hand
(D) that subjects could identify a card in the dealer’s
hand by using thought transference
(E) that subjects are capable to use thought
transference for identifying a card in the dealer’s
hand
Idiom; Rhetorical construction
is sentence is meant to indicate that Joseph
Banks Rhine claimed that a certain experiment
statistically proved that subjects could identify
what symbol was on a card in a dealer’s hand by
using thought transference. e present version
of the sentence does not convey the intended
meaning well, however. What should follow proof
is a statement of the assertion that Rhine claims
the experiment has statistically proved, linked
to the word proof by the word that . Instead proof
is followed by a prepositional phrase for subjects
who. . . .
A is version of the sentence inappropriately
attempts to describe the claim by using a
prepositional phrase, for subjects who. . . .
B Like (A), this version of the sentence
inappropriately attempts to describe the
claim by using a prepositional phrase, for a
card in. . . .
C Like (A) and (B), this version of the sentence
inappropriately attempts to describe the
claim by using a prepositional phrase. While
proof might reasonably be followed by of ,
the phrase that follows the preposition is
ungrammatical, requiring a participle to
modify subjects , such as being able to. . . .
D Correct. is version correctly uses the
idiom proof that followed by an assertion.
E While this version of the sentence correctly
follows proof with that followed by an
assertion, it fails to use the appropriate
idiom with capable ; instead of capable to use ,
it should have capable of using .
e correct answer is D.
676. A long‐term study of some 1,000 physicians indicates
that the more coffee these doctors drank, the more
they had a likelihood of coronary disease.
(A) more they had a likelihood of coronary disease
(B) more was their likelihood of having coronary
disease
(C) more they would have a likelihood to have
coronary disease
(D) greater was their likelihood of having coronary
disease
(E) greater was coronary disease likely
Idiom; Rhetorical construction
is sentence describes the results of a study in
which researchers found a correlation between
the amounts of co ee that people drank and their
likelihood of coronary disease. It most eloquently
expresses this correlation as a comparison of
parallel forms, using the idiom the + comparative
adjective phrase . . . the + comparative adjective
phrase . e two adjective phrases should have the
same grammatical form.
A is version obscures the intended
correlation between co ee and likelihood . e
phrase the more they had a likelihood somewhat
illogically indicates that the research subjects
had likelihood to a greater degree rather than
that their likelihood was greater.
B Although the adverb more is used to
indicate a greater degree or extent in phrases
such as more likely , the adjective more
normally indicates greater quantity. us,
the use of more as an adjective modifying
their likelihood is nonstandard. Di erences in
a particular type of likelihood are normally
thought of as matters of degree, not of
quantity. Greater is the preferred adjective
for indicating such di erences.
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C e conditional verb phrase would have a
likelihood to have is redundant, wordy, and not
comparable to the simple past tense drank .
D Correct. is version uses proper wording
and is clear and concise.
E is completion of the comparison is not
idiomatic; moreover, it is ungrammatical,
attempting to use an adjective greater to
describe an adverb, likely .
e correct answer is D.
677. The intricate structure of the compound insect eye,
having hundreds of miniature eyes called ommatidia,
help explain why scientists have assumed that it
evolved independently of the vertebrate eye.
(A) having hundreds of miniature eyes called
ommatidia, help explain why scientists have
assumed that it
(B) having hundreds of miniature eyes that are called
ommatidia, helps explain why scientists have
assumed that they
(C) with its hundreds of miniature eyes that are
called ommatidia, helps explain scientists’
assuming that they
(D) with its hundreds of miniature eyes called
ommatidia, help explain scientists’ assuming that it
(E) with its hundreds of miniature eyes called
ommatidia, helps explain why scientists have
assumed that it
Agreement; Logical predication
is sentence addresses why scientists have
decided that the vertebrate eye and the insect
eye evolved independently of each other. e
insect eye is much more intricate, with hundreds
of miniature eyes. e sentence needs to be
clear as to what has hundreds of miniature eyes .
e structure or the insect eye ? Furthermore, the
singular subject intricate structure requires the
singular verb helps .
A is wording misleadingly suggests that the
intricate structure has miniature eyes , while
the correct subject of the predicate having
is the compound insect eye . Subject‐verb
agreement is violated.
B is wording misleads as in (A).
Furthermore, the pronoun at the end of the
underlined part of the sentence should refer
back to the compound insect eye , so it cannot
be plural.
C e phrase helps explain scientists’ assuming
correctly agrees with the subject structure .
However, it is nonstandard and awkward;
the use of assuming with the possessive is
unwarranted. Finally, the pronoun at the
end of the underlined part of the sentence
should refer back to the compound insect eye ,
so it cannot be plural.
D e subject structure and the verb help
do not agree in number. As in (C),
explain scientists’ assuming is verbose and
awkward, and the use of the assuming with
the possessive makes the construction
unnecessarily complex.
E Correct. e phrase with its hundreds
correctly refers back to the compound insect
eye . e verb helps correctly agrees with
the subject structure . Finally, the pronoun
it correctly refers to the singular noun the
compound insect eye .
e correct answer is E.
678. In 1979 lack of rain reduced India’s rice production
to about 41 million tons, nearly 25 percent less than
those of the 1978 harvest.
(A) less than those of the 1978 harvest
(B) less than the 1978 harvest
(C) less than 1978
(D) fewer than 1978
(E) fewer than that of India’s 1978 harvest
Logical predication; Diction
e crucial part of this sentence is the latter part,
where India’s 1979 production of 41 million
tons of rice is compared to the production of the
previous year. What was produced in 1979 was
25 percent less than what was produced in 1978.
e grammatical means of comparison have to
express correctly this relationship between the
two harvests. It helps if you think of 41 million
tons of rice as the collective equivalent of the
1979 harvest.
9.8 Sentence Correction Answer Explanations
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A is version exhibits redundant word choice.
e pronoun those refers to the tons of the
1978 harvest. Both harvests are measured
in tons, and it is clearer and simpler to
compare with the harvest itself, not with the
tons of the harvest.
B Correct. is version correctly compares the
1978 harvest with the 1979 harvest.
C is version is illogical. It compares rice
production in tons with a year, 1978.
D In addition to the problem described in
(C) above, this version uses the wrong
comparative adjective. Fewer refers to
countable nouns, while less refers to
quantities. Since the comparative adjective
should refer to rice production, fewer is not
appropriate.
E Since the comparative adjective should refer
to rice production, fewer is not appropriate.
Furthermore, the pronoun that refers back
to India’s rice production [ fewer than the
rice production of India’s 1978 harvest ] and
is redundant. e word harvest is su cient
here to express the comparison.
e correct answer is B.
679. Hurricanes at rst begin traveling from east to west,
because that direction is the way the prevailing winds
in the tropics blow, but they then veer off toward
higher latitudes, in many cases changing direction
toward the east before dissipating over the colder,
more northerly waters or over land.
(A) Hurricanes at rst begin traveling from east
to west, because that direction is the way the
prevailing winds in the tropics blow, but
(B) At rst, hurricanes travel from east to west,
because that is the direction of the prevailing
winds in the tropics, but
(C) While hurricanes travel from east to west at rst,
the direction of the prevailing winds blowing in
the tropics, and
(D) Because hurricanes at rst travel from east to
west, since it is the direction of the prevailing
winds in the tropics,
(E) Hurricanes, beginning by traveling from east
to west, because this is the direction of the
prevailing winds in the tropics,
Rhetorical construction; Grammatical
construction
Hurricanes at rst begin traveling is redundant.
e sentence could start with At rst, hurricanes
travel or with Hurricanes begin traveling ; there is
no need to have both at rst and begin . A concise
version of the sentence would also avoid that
direction is the way the prevailing winds in the
tropics blow . e meaning of way here is already
conveyed by direction .
A At rst and begin are redundant. Also, that
direction is the way the prevailing winds blow
is unnecessarily wordy.
B Correct. is version of the sentence is
grammatically correct and lacks redundancy.
C is sentence begins with a dependent
clause (that is, a clause that cannot stand
on its own), anticipating a main clause
(also known as an independent clause) to
complete the sentence; a main clause does
follow, but it is connected to the initial
dependent clause by the coordinating
conjunction and , which would be
appropriate here only if the initial clause
was of the same grammatical type (that is,
was also a main clause).
D e causal conjunction Because suggests that
the direction in which hurricanes initially
travel causes them later to veer o to the
north, but this make little logical sense.
E is sentence opens with a main subject,
Hurricanes , but this subject has no verb. e
sentence’s main verb, veer , has as a subject
they .
e correct answer is B.
680. Unlike the virginal, whose single set of strings runs
parallel to the front edge of the instrument, the
harpsichord’s several sets of strings are placed at right
angles to its front edge.
(A) whose single set of strings runs parallel to the
front edge of the instrument, the harpsichord’s
several sets of strings are
(B) with a single set of strings running parallel to the
front edge of the instrument, the several sets of
strings of the harpsichord are
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(C) which has a single set of strings that runs parallel
to the front edge of the instrument, in the case of
the harpsichord, several sets of strings are
(D) which has a single set of strings that run
parallel to the front edge of the instrument, the
harpsichord has several sets of strings
(E) in which a single set of strings run parallel to the
front edge of the instrument, the harpsichord’s
several sets of strings are
Parallelism; Agreement
e point of the sentence is to contrast two
instruments, but the sentence has been written to
contrast the virginal with the sets of strings on the
harpsichord. e proper contrast is between the
virginal and the harpsichord.
A e virginal is illogically contrasted with
the sets of strings on the harpsichord. Note
the possessive form harpsichord’s in contrast
to virginal.
B e virginal is illogically contrasted with
the sets of strings on the harpsichord.
C In the case of the harpsichord is not parallel to
the virginal.
D Correct. e contrast is properly drawn
between the virginal and the harpsichord.
E e virginal is illogically contrasted with
the sets of strings on the harpsichord; the
verb run does not agree with the singular
subject set.
e correct answer is D.
681. Although Alice Walker published a number of essays,
poetry collections, and stories during the 1970s, her
third novel, The Color Purple , which was published in
1982, brought her the widest acclaim in that it won both
the National Book Award as well as the Pulitzer Prize.
(A) which was published in 1982, brought her the
widest acclaim in that it won both the National
Book Award as well as the Pulitzer Prize
(B) published in 1982, bringing her the widest
acclaim by winning both the National Book Award
and the Pulitzer Prize
(C) published in 1982, brought her the widest
acclaim, winning both the National Book Award
and the Pulitzer Prize
(D) was published in 1982 and which, winning both
the National Book Award and the Pulitzer Prize,
brought her the widest acclaim
(E) was published in 1982, winning both the National
Book Award as well as the Pulitzer Prize, and
bringing her the widest acclaim
Idiom; Grammatical construction
is sentence claims that the 1982 novel e
Color Purple brought Alice Walker more acclaim
than her many publications in the 1970s.
A e construction both the American Book
Award as well as the Pulitzer Prize is
unidiomatic; the correct idiomatic form is
both x and y .
B Because this sentence uses only participial
phrases in the clause following the initial,
dependent clause, the sentence lacks a main
verb and is therefore ungrammatical.
C Correct. is version correctly uses the
form both x and y and is grammatically
correct.
D e use of which is inappropriate here;
although it would still be rhetorically
inferior to the correct answer (C), this
version would be acceptable if the word
which were deleted.
E Like (A), this version of the sentence uses
the unidiomatic form both x as well as y .
e correct answer is C.
682. Many experts regarded the large increase in credit
card borrowing in March not as a sign that households
were pressed for cash and forced to borrow, rather
a sign of con dence by households that they could
safely handle new debt.
(A) rather a sign of con dence by households that
they could safely
(B) yet as a sign of households’ con dence that it
was safe for them to
(C) but a sign of con dence by households that they
could safely
(D) but as a sign that households were con dent
they could safely
(E) but also as a sign that households were
con dent in their ability safely to
9.8 Sentence Correction Answer Explanations
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Idiom; Logical predication; Parallelism
e structure of this sentence expresses negation
and a rmation: Many experts regarded X not as a
sign that Y, but as a sign of Z . e idiomatic choice
of words for this construction should involve
two clauses introduced by not as … but as…. It is
also important to connect logically the adjective
con dent with the noun it describes, that is,
households. If the adjective con dent or its equivalent
noun con dence is related to other words in the
sentence, the message loses clarity and power.
A e idiomatic choice of words to express the
negation of one clause and the a rmation
of another is not as … but as…. e a rmed
clause is incorrectly introduced by rather.
Furthermore, the preposition by does
not express the idea that households are
con dent. e placement of the restrictive
clause that they could safely handle new debt
after households could also cause confusion.
B e idiomatic choice of words to express the
negation of one clause and the a rmation
of another is not as … but as…. e a rmed
clause is incorrectly introduced by yet as.
e wording it was safe for them [households]
to handle new debt changes the intended
meaning, making the households less clearly
an agent in the handling.
C e idiomatic choice of words to express the
negation of one clause and the a rmation
of another is not as … but as…. e a rmed
clause is incorrectly introduced by but
without the as . Furthermore, the preposition
by does not express the idea that households
are con dent.
D Correct.
is version provides the correct
logical structure. It also expresses the
con dence of households using the most
succinct and direct wording.
E e use of the word also is misleading here.
If the rst embedded clause is negated, the
a rmed second clause cannot also be true.
In addition, in their ability , while expressing
the same idea as could, is redundant and
safely to handle is awkward; the wording in
(D) is superior.
e correct answer is D.
683. A pioneer journalist, Nellie Bly’s exploits included
circling the globe faster than Jules Verne’s ctional
Phileas Fogg.
(A) A pioneer journalist, Nellie Bly’s exploits included
(B) The exploits of Nellie Bly, a pioneer journalist,
included
(C) Nellie Bly was a pioneer journalist including in her
exploits the
(D) Included in the pioneer journalist Nellie Bly’s
exploits are
(E) The pioneer journalist’s exploits of Nellie Bly
included
Logical predication; Modifi cation
is sentence intends to discuss Nellie Bly, a
pioneer journalist who counts among her exploits
a very fast trip around the globe. e current
construction is misleading because it suggests
that Bly’s exploits, not Bly herself, were a pioneer
journalist.
A In this answer choice, a pioneer journalist
incorrectly modi es exploits , rather than
Nellie Bly .
B Correct. is version correctly attributes the
modi er a pioneer journalist to Nellie Bly .
C e wording of this version is illogical
because it makes Nellie Bly the subject of the
verb including .
D Since this event clearly happened in the
past, the tense of the verb are is wrong.
Piling on too many descriptive words for
the noun exploits ( the pioneer journalist Nellie
Bly’s exploits ) makes the phrase unwieldy and
awkward.
E is version can be construed as entailing
that the pioneer journalist and Nellie Bly are
two di erent people, one exploiting the other.
e correct answer is B.
684. In 1913, the largely self-taught Indian mathematician
Srinivasa Ramanujan mailed 120 of his theorems to
three different British mathematicians; only one, G. H.
Hardy, recognized the brilliance of these theorems,
but thanks to Hardy’s recognition, Ramanujan was
eventually elected to the Royal Society of London.
(A) only one, G. H. Hardy, recognized the brilliance
of these theorems, but
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(B) they were brilliant, G. H. Hardy alone recognized,
but
(C) these theorems were brilliant, but only one, G. H.
Hardy recognized;
(D) but, only one, G. H. Hardy, recognizing their
brilliance,
(E) only one G. H. Hardy recognized, but these
theorems were brilliant
Logical predication; Grammatical
construction
e point of the sentence is that only one of the
British mathematicians with whom Srinivasa
Ramanujan initially shared his theorems
recognized their brilliance, but that recognition
was su cient to earn Ramanujan acclaim. e
sentence has been correctly constructed, with
the phrase only one referring clearly to British
mathematicians and the noun theorems repeated to
avoid confusion.
A Correct. e phrase only one refers clearly
to British mathematicians, and the noun
theorems is repeated to avoid confusion.
B ey is intended to refer to theorems but
instead refers to mathematicians, causing
confusion.
C Structured in this way, the sentence does
not make sense. Only one is intended to refer
to G. H. Hardy but instead seems to refer
to theorems, causing confusion. If only one is
taken to refer to G. H. Hardy, the absence of
a comma after the name and the absence of
an object for recognized make the sentence
ungrammatical.
D e sentence is ungrammatical because
G. H. Hardy serves as the subject of a clause
but is not paired with a verb.
E Only one G. H. Hardy recognized incorrectly
implies (in an awkwardly inverted wording
structure) that Hardy recognized only one
theorem; these theorems were brilliant thanks
to Hardy’s recognition illogically suggests
that Hardy’s recognition is what made the
theorems brilliant.
e correct answer is A.
685. Cost cutting and restructuring has allowed the
manufacturing company to lower its projected losses
for the second quarter, and they are forecasting a
pro t before the end of the year.
(A) has allowed the manufacturing company to lower
its projected losses for the second quarter, and
they are forecasting
(B) has allowed for the manufacturing company to
lower its projected losses in the second quarter
and to forecast
(C) have allowed that the manufacturing company
can lower the projected losses for the second
quarter, and to forecast
(D) have allowed the manufacturing company to
lower its projected second-quarter losses and to
forecast
(E) have allowed for the manufacturing company to
lower the projected losses in the second quarter,
as well as forecasting
Agreement; Idiom; Verb form
e point of the sentence is to explain the
two main e ects of the changes made by
the company. However, the singular verb has
allowed does not agree with the compound
subject cost cutting and restructuring, which are
far more plausibly understood as two actions
rather than as two facets of a single action. In
principle, the manufacturing company could be
construed as plural (referring collectively to
the decision makers and spokespeople who are
projecting losses and forecasting a pro t), but
the plural pronoun they does not agree with
the earlier its, which treats the antecedent as
singular.
A e singular verb has allowed does not agree
with the compound subject cost cutting
and restructuring; the plural pronoun they
does not agree with the intended singular
antecedent company.
B e singular verb has allowed does not agree
with the compound subject cost cutting and
restructuring; allowed for is not the correct
idiom.
C Allowed that is not the correct idiom; can
lower and to forecast are not grammatically
parallel.
9.8 Sentence Correction Answer Explanations
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D Correct. e sentence uses the correct
subject–verb combination cost cutting
and restructuring have allowed; the two
occurrences of the pronoun its agree with
each other in treating their antecedent
company as singular; and the two e ects
to lower and to forecast are parallel and
idiomatic.
E Allowed for is not the correct idiom; to lower
and as well as forecasting are not parallel.
e correct answer is D.
686. The Life and Casualty Company hopes that by
increasing its environmental fund reserves to $1.2
billion, that it has set aside enough to pay for
environmental claims and no longer has to use its
pro ts and capital to pay those claims bit by bit, year
by year.
(A) that it has set aside enough to pay for
environmental claims and no longer has
(B) enough has been set aside with which
environmental claims can be paid and it will have
no longer
(C) it has set aside enough for payment of
environmental claims and thus no longer
having
(D) enough has been set aside to pay for
environmental claims, thus no longer having
(E) it has set aside enough to pay for environmental
claims and will no longer have
Grammatical construction; Logical
predication
All predicates need a proper logical subject. Here,
the relevant predicates are the verbs increase ,
set aside , and have. With it as the subject for set
aside —referring back to the Life and Casualty
Company — all three verbs should have this
as their understood subject. With a di erent
subject for set aside , at least one of the other
verbs lacks a proper logical subject. Also, this
sentence uses the word that after hope to start
the subordinate clause, but then incorrectly
repeats the that after the initial adverbial phrase
( by increasing . . . billion ). Only the rst that is
grammatically correct.
A e additional that makes the sentence
ungrammatical. Also, because in this context
the hope is forward‐looking ( bit by bit, year
by year) , it would be preferable to use the
future tense, will no longer have to , instead of
the present no longer has to .
B With enough as the subject of set aside , the
next subject ( it ) is naturally interpreted as
enough , but this is not a logical choice for
the subject of use .
C e phrase no longer having is
ungrammatical when connected to the
rest of the sentence by and , which should
connect two regular clauses; no longer
having . . . is a mere phrase, not a clause,
and no longer has would be correct.
D For no longer having , illogically, the implied
subject is enough ; the implied subject,
instead, should be the company referred to
at the beginning of the sentence.
E Correct. ere is only one that , and will
no longer have to use has its proper logical
subject ( it ) from the clause preceding it.
e correct answer is E.
687. Like ancient Egyptian architectural materials that
were recycled in the construction of ancient Greek
Alexandria, so ancient Greek materials from the
construction of that city were reused in subsequent
centuries by Roman, Muslim, and modern builders.
(A) Like ancient Egyptian architectural materials that
were recycled in the construction of
(B) Like recycling ancient Egyptian architectural
materials to construct
(C) Just as ancient Egyptian architectural materials
were recycled in the construction of
(D) Just as they recycled ancient Egyptian
architectural materials in constructing
(E) Just like ancient Egyptian architectural materials
that were recycled in constructing
Diction; Parallelism
When two situations are asserted to be similar,
the proper way to express this is with the paired
expressions just as . . . so . . ., not like . . . so .
Moreover, the two compared situations should
be expressed as clauses, not as noun phrases. us
the clause ancient Egyptian architectural materials
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were recycled . . . is correct, as opposed to a noun
phrase like ancient Egyptian architectural materials
that were recycled . . .
A Just as and a following clause with a passive
verb are preferred, but instead this option
has like and a following noun phrase ( ancient
Egyptian materials . . . ). It appears, somewhat
implausibly, to say that the ancient Greek
materials were similar to the earlier ancient
Egyptian ones in that both were used by
Roman, Muslim, and modern builders.
B Just as and a following clause with a passive
verb are preferred, but instead this option
has like and a following noun phrase
( recycling ancient Egyptian materials . . . ).
It appears illogically to say that the action
of recycling was similar to the ancient
Greek materials in that both were reused in
subsequent centuries.
C Correct. e expressions just as and so are
paired to link the two clauses in parallel, and
both clauses use the passive construction.
D Just as is used to connect two clauses, which
is good, but the rst clause employs the
active construction rather than the preferred
passive, so there is a failure of parallelism.
Also, it is unclear what they refers to. e
sentence appears to say illogically that some
unidenti ed group’s action of recycling was
similar to the ancient Greek materials’ being
reused.
E Just as introducing a clause with a passive
verb is preferable, but this sentence uses
like and a following noun phrase ( ancient
Egyptian materials . . . ). It appears, somewhat
implausibly, to say that the ancient Greek
materials were similar to the earlier ancient
Egyptian ones in that both were used by
Roman, Muslim, and modern builders.
e correct answer is C.
688. Especially in the early years, new entrepreneurs may
need to nd resourceful ways, like renting temporary
of ce space or using answering services, that make
their company seem large and more rmly established
than they may actually be.
(A) that make their company seem large
(B) to make their companies seem larger
(C) thus making their companies seem larger
(D) so that the companies seem larger
(E) of making their company seem large
Grammatical construction; Diction
e clause beginning with that suggests that a
company can be made to seem better than it
actually is. e comparison signaled by than appears
to be intended to apply to both the size of the
company and the degree to which the company is
rmly established. In that case, it is a mistake to use
large instead of larger . If, on the other hand, large is
not intended to be part of the comparison, it would
be better to clarify this by separating the two topics
in a construction such as make their company seem
large and also make it seem more rmly established. .
. . e phrase resourceful ways suggests purpose, so
ways should connect with to or of, rather than a that
clause to capture the intended meaning.
A Large is the incorrect form to express
comparison; it should be larger ; the that
clause does not adequately capture the idea
of purpose implicit in ways . e singular
company does not agree with the plural
pronoun they . us, the sentence either
commits an agreement mistake or illogically
says that entrepreneurs need to nd ways
to make themselves seem large and more
rmly established.
B Correct. Larger is the correct form to
express the comparative meaning, and to
correctly follows way . Companies agrees with
the plural they .
C e phrase beginning thus making does not
capture the idea of purpose implicit in ways .
D Clauses beginning so that can express purpose,
but do not t with ways in the manner
required here: to
or of is needed after ways .
E Large is the incorrect form to express
comparison; it should be larger . e singular
company does not agree with the plural
pronoun they . us, the sentence either
commits an agreement mistake or illogically
says that entrepreneurs need to nd ways
to make themselves seem large and more
rmly established.
e correct answer is B.
9.8 Sentence Correction Answer Explanations
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689. Unlike the nests of leaf cutters and most other ants,
situated underground or in pieces of wood, raider
ants make a portable nest by entwining their long
legs to form “curtains” of ants that hang from logs or
boulders, providing protection for the queen and the
colony larvae and pupae.
(A) the nests of leaf cutters and most other ants,
(B) the nests of leaf cutters and most other ants,
which are
(C) leaf cutters and most other ants, whose nests
are
(D) leaf cutters and most other ants in having nests
(E) those of leaf cutters and most other ants with
nests
Logical predication
As worded, this sentence draws a contrast
between raider ants and the nests of leaf cutters
and most other ants. e appropriate contrast
would be with leaf cutters and most other ants
themselves, not their nests.
A As indicated above, the appropriate contrast
is between raider ants and other kinds of
ants (namely leaf cutters and most ants). As
worded, this version of the sentence says
something obviously true: of course the
nests of leaf cutters and most other ants do
not make portable nests.
B Like (A), this sentence compares nests with
raider ants. Also, the referent of the relative
pronoun which is ambiguous, possibly
modifying ants , and possibly modifying nests .
C Correct. is version correctly draws the
contrast between raider ants and other kinds
of ants. Furthermore, unlike in (B) and (D),
it is clear here that situated underground or
in pieces of wood applies to the nests of leaf
cutters and most other ants.
D is sentence correctly compares leaf cutters
and other ants with raider ants, but the
prepositional phrase in having nests suggests
that it is raider ants, not leaf cutters and
most other ants, that have nests situated
underground or in pieces of wood; however,
the rest of the sentence indicates that in fact
raider ants’ nests are not situated in such
locations.
E e referent of those is unclear; presumably
it refers to nests , but grammatically it has
no clear antecedent. If it is taken to refer to
nests, those creates an illogical comparison
with raider ant s.
e correct answer is C.
690. Turtles, like other reptiles, can endure long fasts,
in their ability to survive on weekly or even monthly
feedings; however, when food is readily available, they
may eat frequently and grow very fat.
(A) fasts, in their ability to survive
(B) fasts, having their ability to survive
(C) fasts, due to having the ability of surviving
(D) fasts because they are able to survive
(E) fasts because of having the ability of surviving
Idiom; Diction
To express why turtles can endure long fasts—
their ability to survive on only occasional
feedings—it is clearer and more idiomatic to use
because than to use in or having . Also, the noun
ability here requires to introducing a noun phrase
denoting the nature of the ability.
A In does not express the causal relationship
clearly, whereas because does.
B Having does not express the causal
relationship clearly.
C Ability of is incorrect; ability must be followed
by to in order to express the intended
meaning. Due to having the ability is awkward,
nonstandard, and unnecessarily wordy.
D Correct. is option uses because to express
the causal relation and uses to after ability .
E Ability of is incorrect; ability must be
followed by to in order to express the
intended meaning. Because of having the
ability is awkward, nonstandard, and
unnecessarily wordy.
e correct answer is D.
691. Thai village crafts, as with other cultures, have
developed through the principle that form follows
function and incorporate readily available materials
fashioned using traditional skills.
(A) as with
(B) as did those of
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(C) as they have in
(D) like in
(E) like those of
Logical predication; Diction; Verb form
e phrase as with other cultures is initially
confusing given that no culture has been
speci cally mentioned; ai village culture is
indirectly referenced by the mention of ai village
crafts , so perhaps that is what is meant. But then,
looking at the phrase in context, it becomes clear
that the sentence is intended to indicate that the
crafts of other cultures are similar in certain ways
to ai village crafts. us, the sentence should say
those of other cultures . Furthermore, the use here of
as with is questionable. To do the job it is supposed
to do here (to indicate that the crafts of ai
villages are like the crafts of other cultures in a
particular way), as with should be at the beginning
of the sentence: As with the crafts of other cultures,
ai village crafts have developed. . . . Alternatively,
like could be used here instead of as with .
A e appropriate comparison is between ai
village crafts and those (i.e., crafts) of other
cultures, not the other cultures themselves.
Additionally, like would be more appropriate
here than as with .
B e verb form here is incorrect. [ D ] id is not
parallel to have later in the sentence. e
phrase as have those of other cultures would be
parallel, but it is in the wrong position. To be
correct, it would need to occur after the main
verb is introduced: ai village crafts have
developed, as have those of other cultures, . . .
C e use of the pronoun they is inaccurate;
the reader is likely to take its antecedent
to be ai village crafts , not crafts .
Furthermore, even if the pronoun here
were not problematic, if the construction as
they have in other cultures is used, it should
occur after the main verb ( have developed )
is introduced.
D e comparative term like
compares two
nouns or noun phrases, but in this version
of the sentence, like compares a noun
( crafts ) with a prepositional phrase ( in other
cultures ).
E Correct. [ T ] hose of other cultures clearly
refers to the crafts of other cultures; like
is appropriate for making a comparison
between two sorts of things ( crafts ).
e correct answer is E.
692. Tropical bats play important roles in the rain forest
ecosystem, aiding in the dispersal of cashew, date,
and g seeds; pollinating banana, breadfruit, and
mango trees; and indirectly help produce tequila by
pollinating agave plants.
(A) pollinating banana, breadfruit, and mango trees;
and indirectly help produce
(B) pollinating banana, breadfruit, and mango trees;
and indirectly helping to produce
(C) pollinating banana, breadfruit, and mango trees;
and they indirectly help to produce
(D) they pollinate banana, breadfruit, and mango
trees; and indirectly help producing
(E) they pollinate banana, breadfruit, and mango
trees; indirectly helping the producing of
Logical predication; Parallelism
is sentence expresses a list of the roles tropical
bats play in the rain forest ecosystem. Since
these roles are enumerated in a list, and since
the rst member of the list is already provided,
it is necessary to maintain the same structure
for the rest of the members of the list in order
to maintain parallelism and clarity. Note that
semicolons separate the members of the list,
leaving the commas to mark series of items
within each member of the list.
A In this version, the third member of the list
does not maintain the ‐ ing verb form that
the two previous members use.
B Correct. is version correctly maintains
the parallel structure ( aiding in …;
pollinating …; and helping … ).
C In this version, the third member of the
list does not maintain the ‐ ing verb form
of the two previous members of the list. In
addition, this member of the list includes a
subject ( they ) while the other members do
not, again violating parallelism.
9.8 Sentence Correction Answer Explanations
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D In order to maintain parallelism the verb
that is the member of the list has to be in
the ‐ ing form, not its complement. us,
the ‐ ing has to be on the verb help , not on
produce .
E Although this version maintains parallelism
throughout, the phrase helping the producing
is an incorrect construction in English.
e correct answer is B.
693. Discussion of greenhouse effects have usually had as
a focus the possibility of Earth growing warmer and to
what extent it might, but climatologists have indicated
all along that precipitation, storminess, and temperature
extremes are likely to have the greatest impact on people.
(A) Discussion of greenhouse effects have usually
had as a focus the possibility of Earth growing
warmer and to what extent it might,
(B) Discussion of greenhouse effects has usually
had as its focus whether Earth would get warmer
and what the extent would be,
(C) Discussion of greenhouse effects has usually
focused on whether Earth would grow warmer
and to what extent,
(D) The discussion of greenhouse effects have
usually focused on the possibility of Earth getting
warmer and to what extent it might,
(E) The discussion of greenhouse effects has usually
focused on whether Earth would grow warmer
and the extent that is,
Agreement; Parallelism
e sentence contrasts climatologists’ views
concerning greenhouse e ects with other views
that emphasize global warming. e main subject
of the sentence is discussion . . ., which is singular,
so the main verb should be singular. e two
things that are said to be the focus of discussion
should be in parallel form.
A e plural verb have . . . had does not agree
with the singular subject discussion . e
phrases the possibility . . . warmer and to what
. . . might are not parallel.
B e verb form has had as its focus is
unnecessarily wordy; the noun clauses are
parallel in form, but it is not clear what the
extent refers to.
C Correct. is has correct subject‐verb
agreement, eliminates the wordiness of the
original sentence, and the phrases whether . . .
warmer and to what extent are parallel.
D e singular subject discussion does not agree
with the plural verb have focused . e possibility
of . . . is not parallel with to what extent. . . .
E e two phrases following on are not in
parallel form. What that refers to in the
extent that is is unclear.
e correct answer is C.
694. In the seventh century B.C., the Roman alphabet
was adapted from the Etruscan alphabet, which
in turn had been adapted in the previous century
from a western Greek alphabet, which itself had
been adapted earlier in the same century from the
Phoenician alphabet.
(A) which itself had been adapted earlier
(B) adapting itself earlier
(C) itself being adapted earlier
(D) having been earlier adapted itself
(E) earlier itself having been adapted
Rhetorical construction; Verb form; Logical
predication
is sentence describes a string of adaptations of
the alphabet, tracing back from the seventh century
BC through two points in the eighth century
BC. Because the latest of the three adaptations is
temporally located in past tense, earlier adaptations
should be located in the past perfect tense.
A Correct. is sentence is properly
constructed and uses the appropriate verb
forms for the relationships among the
events that it describes.
B It is unclear what the participial phrase
adapting itself earlier . . . refers to. e
present participle could be used for an
event that was simultaneous with, or
part of, the event mentioned before
the underlined portion. However, it is
inappropriate for describing an event
that took place even earlier than the
seventh century BC, which has already
been designated in the sentence as past
tense. e re exive form adapting itself is
nonsensical in this sentence.
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C e present tense of the re exive participial
phrase is inappropriate for describing an
event prior to the seventh century BC, given
that the seventh century BC has already
been designated in the sentence as past
tense.
D Without commas around itself , the pronoun
appears to be re exive. e combination of
passive and re exive then makes no sense.
If itself is intended simply for emphasis,
rather than as a re exive pronoun, it would
be preferable, in this context, to set it o
with commas. But if it were intended in that
way, it would seem to refer to the Roman
alphabet, and the claim made in the sentence
would be confusing and nearly nonsensical.
is modi er is confusingly placed before
the designation of time ( in the same century )
and source ( from the Phoenician alphabet ).
E e adverb earlier is misplaced before the
pronoun itself ; it should be immediately
before the phrase in the same century .
e correct answer is A.
695. With corn, soybean, and wheat reserves being
low enough so a poor harvest would send prices
skyrocketing, grain futures brokers and their clients are
especially interested in weather that could affect crops.
(A) being low enough so
(B) so low such that
(C) so low that
(D) that are low enough so
(E) that are so low such that
Idiom; Rhetorical construction
is sentence opens with a long participial
phrase ( With . . . skyrocketing ) that describes
conditions within which the action of the main
clause ( grain futures brokers . . . crops ) occurs.
e opening phrase compares one economic
condition (grain reserve levels) with another
(prices) using the idiomatic expression so low that.
Some of the phrases used in expressing this kind
of comparison are wordy and indirect ( being low
enough so ). us, they are not standard in written
English, even though they may be accepted in
some informal speaking contexts.
A is phrase is wordy and unidiomatic.
B is phrase combines two idioms ( so . . . that
and such that ) in a way that does not clearly
make sense. It is wordy and redundant; both
so . . . that and such signal comparison.
C Correct. is wording is standard, clear, and
direct.
D e relative clause introduced by that are
makes this phrase unnecessarily wordy and
cumbersome; enough and so are redundant.
E is version of the phrase is the most
redundant of all—piling comparative terms
one upon the other ( that are so and such ).
e repetition obscures instead of develops
meaning.
e correct answer is C.
696. By 1940, the pilot Jacqueline Cochran held seventeen
of cial national and international speed records,
and she earned them at a time when aviation was
still so new for many of the planes she ew to be of
dangerously experimental design.
(A) and she earned them at a time when aviation was
still so new for many of the planes she ew to be
(B) earning them at a time that aviation was still so
new for many of the planes she ew to be
(C) earning these at a time where aviation was still
so new that many of the planes she ew were
(D) earned at a time in which aviation was still so
new such that many of the planes she ew were
(E) earned at a time when aviation was still so new
that many of the planes she ew were
Rhetorical construction; Diction
Since this is a complex sentence with a lot of
elements, its rhetorical construction is crucial
in order to maintain e ective communication.
e underlined part emphasizes that on top
of earning seventeen speed records, the pilot
Jacqueline Cochran did so at a time when planes
were of dangerous experimental design because
aviation was still so new.
A is version is too wordy and does not
contribute to clarity. Economical, clear
expression connects earned directly with the
noun speed records , which it modi es.
9.8 Sentence Correction Answer Explanations
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B Here, the word earning takes the pilot
herself, not the records , as its subject.
However, earning is close to the records , not
to Jacqueline Cochran , making this sentence
hard to process. In addition, the causal
relationship between aviation being new and
planes being of experimental design is more
e ectively communicated by the structure so
new that many X were Y , not by the structure
so new for many X to be Y .
C e word earning takes the pilot herself, not
the records, as its subject. However, earning
is close to the records , not to Jacqueline
Cochran , making this sentence hard to
understand. Furthermore, the use of where to
modify time is wrong; where refers to place.
D e correct pronoun for time is when . e
word such is redundant within so new that
many X were Y .
E Correct. e word earned is close to the
noun it modi es, speed records. is version
uses the clearest expression of causal
relationship: so new that many X were Y.
e correct answer is E.
697. The foundation works to strengthen local and
regional agricultural markets and cooperating with
governments, improving access for farmers for
productive resources such as land and credit.
(A) cooperating with governments, improving access
for farmers for
(B) cooperates with governments to improve access
for farmers to
(C) cooperate with governments for improvements
of access for farmers to
(D) cooperate with governments and improve
accessibility for farmers for their
(E) in cooperation with governments to improve
access for farmers for
Parallelism; Rhetorical construction
As written, this sentence does not clearly
indicate whether and is intended to conjoin
two things that the foundation does (working
to strengthen markets and cooperating with
governments) or two things that the foundation
works to accomplish (strengthening markets and
cooperating with governments). e latter is less
plausible because of the redundancy of works to
cooperate . In the former, the proper verb form,
parallel with the present-tense works , would be
cooperates . In the latter, the proper verb form,
parallel with the in nitive to strengthen , would
be to cooperate or simply cooperate. Only one of
the answer choices resolves the uncertainty of
meaning in a coherent and well-formed way.
A Cooperating is incorrect, since it is not in the
same form as either works or to strengthen .
B Correct. is version correctly represents
the foundation’s two actions by putting
the verbs works and cooperates in parallel
form. Cooperates . . . to improve is the most
concise phrasing to express the purpose of
improving access.
C Cooperate . . . for improvements of access
for farmers is awkwardly phrased and
unnecessarily wordy.
D Cooperate . . . and improve accessibility
for farmers is awkwardly phrased and
unnecessarily wordy.
E In cooperation destroys the parallelism required
by works to : there should be a verb following
works to , not this prepositional phrase.
e correct answer is B.
698. A professor at the university has taken a sabbatical to
research on James Baldwin’s books that Baldwin wrote
in France while he was living there .
(A) on James Baldwin’s books that Baldwin wrote in
France while he was living there
(B) about the books James Baldwin wrote in France
(C) into James Baldwin’s books written while in France
(D) on the books of James Baldwin, written while he
lived in France
(E) the books James Baldwin wrote while he lived in
France
Diction; Rhetorical construction
e phrasing of this sentence is wordy and
redundant: books that Baldwin wrote in France
while he was living there could more concisely be
expressed with books James Baldwin wrote while
he lived in France . e verb research requires a
direct object, not a preposition followed by its
object.
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A On incorrectly follows to research , and books
that Baldwin wrote in France while he was
living there includes redundant information.
B About incorrectly follows to research .
C Into incorrectly follows to research . Given
this sentence structure, while in France
seems to say, illogically, that the books were
written while they were in France.
D On incorrectly follows to research ; also, there
is no need to make written while he lived in
France into an independent phrase instead
of a relative clause.
E Correct. Research takes a direct object,
which describes the books directly without
redundancy.
e correct answer is E.
699. Researchers now regard interferon as not a single
substance, but it is rather a biological family of
complex molecules that play an important, though not
entirely de ned, role in the immune system.
(A) as not a single substance, but it is rather a
biological family of complex molecules that play
(B) as not a single substance but as a biological
family of complex molecules playing
(C) not as a single substance but as a biological
family of complex molecules that play
(D) not to be a single substance but rather a
biological family of complex molecules playing
(E) not as a single substance but instead as being a
biological family of complex molecules that play
Parallelism; Rhetorical construction
is sentence draws a contrast between how
interferon is and is not regarded by researchers.
However, the two parts of the contrast are not
expressed in parallel form since the rst is a
prepositional phrase (as not a single substance),
and the second is a clause (it is rather a biological
family). Furthermore, the wording regard
interferon as not is awkward and confusing. For
clarity and proper parallelism, the contrast should
be constructed using the expression not as X but
as Y, where X and Y are both noun phrases.
A e contrast is not expressed using parallel
grammatical structure, and regard interferon
as not is awkward and confusing.
B e wording regard interferon as not is awkward
and confusing and violates proper parallelism.
C Correct. e contrast is expressed using the
parallel structure not as a single substance but
as a biological family.
D e main defect here is that regard interferon
not to be a single substance is unidiomatic; regard
... as ... is the correct form; and completing
the parallelism correctly would require the
repetition of as, in the phrase but rather as ...
E e contrast is not expressed using parallel
grammatical structure since a single substance
is a noun phrase, while being a biological
family is a participial phrase; omitting the
unnecessary words being and instead would
improve the sentence.
e correct answer is C.
700. The remarkable similarity of Thule artifacts throughout
a vast region can, in part, be explained as a very rapid
movement of people from one end of North America to
the other.
(A) The remarkable similarity of Thule artifacts
throughout a vast region can, in part, be
explained as
(B) Thule artifacts being remarkably similar
throughout a vast region, one explanation is
(C) That Thule artifacts are remarkably similar
throughout a vast region is, in part, explainable as
(D) One explanation for the remarkable similarity of
Thule artifacts throughout a vast region is that
there was
(E) Throughout a vast region Thule artifacts are
remarkably similar, with one explanation for this
being
Logical predication; Grammatical
construction; Rhetorical construction
e intended meaning of the sentence is that
the rapid movement of people across North
America is one explanation of the similarity of
ule artifacts throughout a vast region . As worded,
however, the sentence is illogical: e sentence
indicates that the similarity in artifacts was a
rapid movement of people, which makes no sense.
Instead of equating similarity with movement,
the sentence needs to identify this movement of
people as a cause of similarity among artifacts.
9.8 Sentence Correction Answer Explanations
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A As worded, this version of the sentence makes
the illogical statement that the similarity
among artifacts is explainable as a very rapid
movement . It should specify that the similarity
of artifacts may be a consequence of the rapid
population movement.
B is version of the sentence is syntactically
awkward, and leaves unclear what the main
subject, one explanation , is supposed to be an
explanation of.
C Like (A), this version of the sentence
equates the similarity of artifacts with
the movement of people, when a causal
connection is what is intended.
D Correct. is version adequately expresses
the intended causal connection.
E is version is awkward, introducing the
causal connection with the unnecessarily
wordy and indirect string of prepositional
phrases, with one explanation for this. . . .
e correct answer is D.
701. The widely accepted big bang theory holds that the
universe began in an explosive instant ten to twenty
billion years ago and has been expanding ever since.
(A) that the universe began in an explosive instant
ten to twenty billion years ago and has been
expanding
(B) that the universe had begun in an explosive
instant ten to twenty billion years ago and had
been expanding
(C) that the beginning of the universe was an
explosive instant ten to twenty billion years ago
that has expanded
(D) the beginning of the universe to have been an
explosive instant ten to twenty billion years ago
that is expanding
(E) the universe to have begun in an explosive
instant ten to twenty billion years ago and has
been expanding
Logical predication; Verb form
e sentence describes the central tenet of a
theory about how the universe began. e focus
of the second clause should be consistently on
the subject the universe , and all verbs in the clause
beginning with that must describe what the
universe did at the initial explosive moment.
A Correct. Both verbs in the second clause
correctly take universe as their subject.
B Had begun is the wrong tense because it
describes action that occurred farther in the
past than some other, speci ed past action.
C e relative clause that has expanded
describes instant , which makes no sense.
D e beginning of the universe to have been … is
unnecessarily indirect and wordy; illogically
suggests that beginning is expanding, not the
universe.
E e verb phrases to have begun and has been
expanding both reference the same subject
of the clause, universe , and therefore need to
be parallel.
e correct answer is A.
702. Between 14,000 and 8,000 B.C. the ice cap that
covered northern Asia, Europe, and America began
to melt, uncovering vast new areas that were to be
occupied by migrating peoples moving northward.
(A) began to melt, uncovering vast new areas that
were to be occupied
(B) began melting, to uncover vast new areas to be
occupied
(C) began, by melting, to uncover vast new areas for
occupation
(D) began, after melting, uncovering vast new areas
which are to be occupied
(E) would begin to uncover, through melting, vast
new areas for occupation
Verb form; Logical predication
e sentence explains what happened when
an ice cap began to melt. e participial phrase
uncovering vast new areas succinctly describes
the immediate e ects of the melting. e verb
form were to be occupied is used to indicate that
occupation would take place at a time in the
future from the time of the melting.
A Correct. e sentence succinctly expresses
immediate and future e ects of the melting
of an ice cap.
B e in nitive to uncover incorrectly implies
that the ice cap melted for the purpose of
uncovering new areas.
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C Since melting is what caused new areas to be
uncovered, that word should be part of the
main verb, not placed in the nonrestrictive
prepositional phrase by melting.
D It does not make sense to say that the ice
cap began ... uncovering new areas after it
had melted—since the ice cap no longer
existed in the areas where it had melted.
E Since melting is what caused new areas to be
uncovered, that word should be part of the
main verb, not placed in the nonrestrictive
prepositional phrase through melting.
e correct answer is A.
703. Bengal‐born writer, philosopher, and educator
Rabindranath Tagore had the greatest admiration
for Mohandas K. Gandhi the person and also as a
politician, but Tagore had been skeptical of Gandhi’s
form of nationalism and his conservative opinions
about India’s cultural traditions.
(A) for Mohandas K. Gandhi the person and also as
a politician, but Tagore had been
(B) for Mohandas K. Gandhi as a person and as a
politician, but Tagore was also
(C) for Mohandas K. Gandhi not only as a person
and as a politician, but Tagore was also
(D) of Mohandas K. Gandhi as a person and as also
a politician, but Tagore was
(E) of Mohandas K. Gandhi not only as a person and
as a politician, but Tagore had also been
Rhetorical construction; Parallelism
is sentence describes the writer and philosopher
Tagore’s two types of feelings for Gandhi. e
underlined part of the sentence has to express
correctly the time line of these two feelings (they
happened simultaneously). e underlined part
also has to express the correct relationship between
the complements of admiration and skepticism.
A To maintain parallelism, it is important for
two conjoined phrases to be of the same
grammatical type. us, it is appropriate to
conjoin Gandhi the person and the politician, or
Gandhi as a person and as a politician, but it is
nonstandard in English to mix and match. In
addition, the use of the past perfect tense had
been places the skepticism earlier on the time
line than the admiration, which is misleading.
B Correct. is version correctly conjoins two
parallel phrases, Gandhi as a person and as
a politician , and, in using two simple past
tenses to introduce the two emotions, marks
them as holding at the same time.
C e phrase not only X but also Y matches
the meaning of this sentence: Tagore had
not only admiration but also skepticism.
However not only has to precede admiration
for this rhetorical construction to be parallel.
D e noun admiration as it is positioned in
this sentence should take the preposition for ,
not of , since it refers to a person. e adverb
also is redundant because it expresses the
same meaning as the conjunction and .
E As in (D), the noun admiration should take
the preposition for . As in (C), the rhetorical
structure of not only X but also Y is violated.
Finally, the use of the past perfect tense had
been is misleading with respect to the time
line.
e correct answer is B.
704. Traf c safety of cials predict that drivers will be
equally likely to exceed the proposed speed limit as
the current one.
(A) equally likely to exceed the proposed speed limit
as
(B) equally likely to exceed the proposed speed limit
as they are
(C) equally likely that they will exceed the proposed
speed limit as
(D) as likely that they will exceed the proposed
speed limit as
(E) as likely to exceed the proposed speed limit as
they are
Idiom; Parallelism
is sentence reports on a prediction that compares
the likelihood of drivers exceeding a proposed new
speed limit with the likelihood of drivers exceeding
the current speed limit. e idiom as x as y , rather
than the incorrect form equally . . . as , should be
used to express the comparison.
9.8 Sentence Correction Answer Explanations
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A Equally likely . . . as is not an idiomatic form
of comparison.
B is also o ers a nonidiomatic form of
comparison.
C e comparison is expressed nonidiomatically.
Also, the drivers will be equally likely should
be followed by to exceed rather than by that
they will exceed . e resulting sentence is
wordy and structurally awed.
D e resulting sentence is wordy and
structurally awed. e idiomatic phrase
as x as y is somewhat in use, but as likely
that they is awkward, and the comparison is
unclear and not parallel.
E Correct. e idiomatic phrase as x as y is
properly used, and the comparison is clear
and parallel.
e correct answer is E.
705. Written early in the French Revolution, Mary
Wollstonecraft’s A Vindication of the Rights of Man
(1790) and A Vindication of the Rights of Woman
(1792) attributed Europe’s social and political ills to be
the result of the dominance of aristocratic values and
patriarchal hereditary privilege.
(A) Mary Wollstonecraft’s A Vindication of the Rights
of Man (1790) and A Vindication of the Rights
of Woman (1792) attributed Europe’s social and
political ills to be the result of
(B) Mary Wollstonecraft’s A Vindication of the Rights
of Man (1790) and A Vindication of the Rights
of Woman (1792) attributed Europe’s social and
political ills to result from
(C) Mary Wollstonecraft’s A Vindication of the Rights
of Man (1790) and A Vindication of the Rights
of Woman (1792) attributed Europe’s social and
political ills to
(D) in A Vindication of the Rights of Man (1790)
and A Vindication of the Rights of Woman
(1792), Mary Wollstonecraft attributed
Europe’s social and political ills to have been
the result of
(E) Mary Wollstonecraft, in A Vindication of the
Rights of Man (1790) and A Vindication of the
Rights of Woman (1792), attributed Europe’s
social and political ills to
Logical predication; Idiom
e phrase at the beginning needs a subject
for written ; most logically here it would
be the books mentioned written by Mary
Wollstonecraft; any other main‐clause subject
is therefore incorrect. e verb attribute
idiomatically requires the preposition to
followed by a noun phrase, not the in nitive
marker to followed by a verb.
A e main subject is correctly predicated of
written , but attribute is incorrectly followed
by the in nitive to plus a verb ( be ).
B e main subject is correctly predicated of
written , but attribute is incorrectly followed
by the in nitive to plus a verb ( result ).
C Correct. e main subject is correctly
predicated of written , and attribute is
correctly followed by the preposition to .
D e subject of the main clause is Mary
Wollstonecraft , and so this phrase is illogically
forced to be taken as the subject of written .
Also, attribute is incorrectly followed by to
plus a verb ( have been ).
E e subject of the main clause is Mary
Wollstonecraft , and so this phrase is
illogically forced to be taken as the subject
of written .
e correct answer is C.
706. Using study groups managed by the principal popular
organizations and political parties, the Swedish public
was informed by the government about energy and
nuclear power .
(A) the Swedish public was informed by the
government about energy and nuclear power
(B) the government informed the Swedish public
about energy and nuclear power
(C) energy and nuclear power information was given
to the Swedish public by the government
(D) information about energy and nuclear power was
given to the Swedish public by the government
(E) the public of Sweden was given energy and
nuclear power information by the government
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Logical predication; Rhetorical construction
is sentence tries to describe a situation in which
the government used study groups to inform the
Swedish public. erefore, it is incorrect to use
the Swedish public as the subject of inform in this
sentence, because doing so in this case illogically
makes the Swedish public the subject of using as
well. Additionally, inform is a more concise and
direct way to express the idea in give information .
A Using the Swedish public as the subject of the
main clause incorrectly makes it the subject
of using as well.
B Correct. Using the government as the
main subject correctly allows it to count
as the subject of using; inform is a concise
phrasing for the main action of the sentence.
C Energy and nuclear power information
does not work as the subject of the main
clause, since this also, illogically, makes it
the subject of using . Also, this phrase delays
the reader’s understanding of the important
noun information (a clearer phrasing is
information about energy and nuclear power )
and employs give information rather than
the more concise inform .
D Energy and nuclear power information does
not work as the main clause subject, since
this also, illogically, makes it the subject of
using . In addition, this version awkwardly
uses give information to instead of the more
concise inform .
E e public of Sweden is awkward compared
to the Swedish public , and in any case is
illogically taken as the subject of using;
given . . . information could be phrased more
concisely with inform.
e correct answer is B.
707. The use of the bar code, or Universal Product Code,
which was created in part to enable supermarkets to
process customers at a faster rate, has expanded
beyond supermarkets to other retail outlets and
have become readily accepted despite some initial
opposition when it was rst introduced in 1974 .
(A) have become readily accepted despite some
initial opposition when it was rst introduced
in 1974
(B) has become readily accepted despite some
initial opposition when they were rst introduced
in 1974
(C) have become readily accepted despite some
initial opposition when rst introduced in 1974
(D) has become readily accepted despite some
initial opposition when the bar code was rst
introduced in 1974
(E) bar codes have become readily accepted
despite some initial opposition when it was rst
introduced in 1974
Agreement; Rhetorical construction
e subject of this sentence is the use of the bar
code , the main noun of which is the singular use ;
thus, the corresponding main verb should be in
the singular form has , not the plural have . e
actual subject for this verb is merely understood,
but when it is present, any pronoun that refers
back to it must agree with it in number.
A e verb form have does not agree with
the sentence’s subject. e referent of it is
potentially unclear.
B Has is correct; however, the rest of its clause
is badly worded, because its subject they
does not clearly refer back to the singular
Universal Product Code (or bar code ); a better
choice is it .
C e plural have does not agree with the
singular subject use .
D Correct. e verb is in the correct form has ,
and using bar code as the last clause’s subject
avoids an agreement problem.
E Restating the subject as the plural bar codes
allows the following verb to be have , but it is
then incorrect to use it later in the sentence,
since it does not agree in number with bar
codes .
e correct answer is D.
708. The Organization of Petroleum Exporting Countries
(OPEC) had long been expected to announce a
reduction in output to bolster sagging oil prices, but
of cials of the organization just recently announced
that the group will pare daily production by 1.5 million
barrels by the beginning of next year, but only if non‐
OPEC nations, including Norway, Mexico, and Russia,
were to trim output by a total of 500,000 barrels a day.
9.8 Sentence Correction Answer Explanations
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(A) year, but only if non‐OPEC nations, including
Norway, Mexico, and Russia, were to trim output
(B) year, but only if the output of non‐OPEC nations,
which includes Norway, Mexico, and Russia, is
trimmed
(C) year only if the output of non‐OPEC nations,
including Norway, Mexico, and Russia, would be
trimmed
(D) year only if non‐OPEC nations, which includes
Norway, Mexico, and Russia, were trimming
output
(E) year only if non‐OPEC nations, including Norway,
Mexico, and Russia, trim output
Rhetorical construction; Logical predication
e underlined part of this sentence deals with
the conditions under which OPEC members
will lower their own oil production by 1.5
million barrels by the beginning of next year. e
important thing to notice here is the following
logical relation: X will do something only if Y does
something else .
A is version has redundant words, were to in
front of trim , that do not add anything more
in meaning. Furthermore, were to trim is
not the proper verb form to accompany will
pare . e addition of but before only is also
redundant.
B is version uses the passive construction in
the conditional clause only if the output … is
trimmed. is use of the passive voice makes
this sentence vague; it is now unclear who
needs to trim the output of non‐OPEC
nations. Finally, the addition of but before
only is redundant.
C As in (B), this version also introduces
vagueness by using the passive construction.
In addition, would in front of the passive
verb be trimmed is redundant.
D is version uses an active verb, but in the
past progressive form, were trimming . e
progressive tense denotes actions in progress,
so its use is not normally warranted in
conditional sentences such as this one.
E Correct. is version uses the correct and
most concise conditional structure, without
redundancies.
e correct answer is E.
709. Not trusting themselves to choose wisely among the
wide array of investment opportunities on the market,
stockbrokers are helping many people who turn to them
to buy stocks that could be easily bought directly.
(A) stockbrokers are helping many people who turn
to them to buy stocks that could be easily
(B) stockbrokers are helping many people who are
turning to them for help in buying stocks that
they could easily have
(C) many people are turning to stockbrokers for help
from them to buy stocks that could be easily
(D) many people are turning to stockbrokers for help
to buy stocks that easily could have been
(E) many people are turning to stockbrokers for help
in buying stocks that could easily be
Logical predication; Grammatical
construction; Verb form
is sentence is intended to be about people who,
because they do not trust themselves to make
wise investment decisions, turn to stockbrokers
for advice. As the sentence is worded, however,
it is stockbrokers who do not trust themselves to
choose wisely. e sentence is made even more
incomprehensible by the peculiar placement of the
adverbs in the phrase, could be easily bought directly .
A is version of the sentence incorrectly
identi es the subject described by the opening
modi er as stockbrokers ; the adverb easily is
misplaced in the phrase could be easily bought .
B As in (A), the opening clause illogically
modi es stockbrokers rather than many people .
e tense of the verb phrase could easily
have bought does not match the tense of are
helping earlier in the main clause.
C Although the opening modi er is correctly
attached to people rather than stockbrokers ,
the sentence is unnecessarily wordy ( for help
from them ).
D To buy is not idiomatic in this context— in
buying would be correct—and the tense
of the verb could have been does not match
the tense of the verb earlier in the clause;
the point is not that people are turning to
stockbrokers for help in buying stocks that
at some earlier time could have been bought
directly, but rather that the stocks could be
bought by the people directly at the very time
they are seeking help from the stockbrokers.
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E Correct. e opening clause correctly
modi es many people , and the adverb is
correctly placed.
e correct answer is E.
710. There are several ways to build solid walls using just
mud or clay, but the most extensively used method
has been the forming of bricks out of mud or clay, and,
after some preliminary air drying or sun drying, they
are laid in the wall in mud mortar.
(A) the forming of bricks out of mud or clay, and,
after some preliminary air drying or sun drying,
they are laid
(B) forming the mud or clay into bricks, and, after
some preliminary air drying or sun drying, to lay
them
(C) having bricks formed from mud or clay, and,
after some preliminary air drying or sun drying,
they were laid
(D) to form the mud or clay into bricks, and, after
some preliminary air drying or sun drying, to lay
them
(E) that bricks were formed from mud or clay, which,
after some preliminary air drying or sun drying,
were laid
Parallelism; Verb form
e purpose of the sentence is to describe the
historically most popular method of building
walls. e rst clause announces this topic and
the second clause describes the particular method.
e clearest, most e cient way to accomplish
these two pieces of business is to use a parallel
structure. e ways to build in the rst clause is
narrowed to the single way to form and to lay in
the second clause. ere is no need to alternate
the verb phrases between active and passive voice
or to shift tenses.
A e active gerund phrase the forming of
bricks does not t with the passive verb
phrase that follows ( they are laid ).
B e verb phrases forming the mud … and to
lay them are not parallel.
C In addition to faulty parallelism between
having bricks formed and they were laid , the
tense in the second half of the sentence
unaccountably shifts from present to past.
D Correct. e phrases to form and to lay in
the second clause are parallel to to build in
the rst clause.
E e relative clause beginning with which
apparently (but nonsensically) describes the
closest nouns, mud or clay , rather than bricks .
e correct answer is D.
711. A surge in new home sales and a drop in weekly
unemployment claims suggest that the economy might
not be as weak as some analysts previously thought.
(A) claims suggest that the economy might not be
as weak as some analysts previously thought
(B) claims suggests that the economy might not be
so weak as some analysts have previously thought
(C) claims suggest that the economy might not be
as weak as have been previously thought by
some analysts
(D) claims, suggesting about the economy that it
might not be so weak as previously thought by
some analysts
(E) claims, suggesting the economy might not be as
weak as previously thought to be by some analysts
Agreement; Grammatical construction
e plural subject of this sentence ( surge and
drop ) requires a plural verb, suggest . e object of
this verb, the clause beginning with that , should
be presented in as clear and direct a manner as
possible.
A Correct. e plural subject is matched with
a plural verb.
B e singular verb suggests does not match
the plural subject of the sentence.
C e sentence o ers no plural subject to t
the passive verb have been thought .
D is construction is awkward, wordy, and
imprecise; it also lacks a main verb; there is
no reason to use passive voice, and suggesting
about the economy that it might … introduces
extra words that contribute nothing to the
meaning of this sentence fragment.
E e passive construction makes this
unnecessarily wordy; the lack of a main verb
makes this a sentence fragment.
e correct answer is A.
9.8 Sentence Correction Answer Explanations
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712. Retail sales rose 0.8 of 1 percent in August,
intensifying expectations that personal spending in the
July–September quarter more than doubled that of the
1.4 percent growth rate in personal spending for the
previous quarter.
(A) that personal spending in the July–September
quarter more than doubled that of
(B) that personal spending in the July–September
quarter would more than double
(C) of personal spending in the July–September
quarter, that it more than doubled
(D) of personal spending in the July–September
quarter more than doubling that of
(E) of personal spending in the July–September
quarter, that it would more than double that of
Verb form; Logical predication
e sentence explains the expectations that resulted
from a past retail sales trend. Since expectations
look to the future but are not yet realized, the
relative clause explaining these expectations should
be conditional, employing the auxiliary verb would.
A e simple past‐tense verb form does
not express the forward‐looking sense of
expectations .
B Correct. By using the verb would double,
this concise sentence indicates that the
expectation has not yet been realized.
C is construction is awkward, announcing the
topic ( personal spending ) and then elaborating
in a relative clause that restates this topic as it .
D Although this option is not technically
wrong, it is less clear and graceful than (B).
E Like (C), this sentence is awkward and
unnecessarily wordy, announcing the topic
and then using an additional clause to
elaborate on it.
e correct answer is B.
713. In the early part of the twentieth century, many
vacationers found that driving automobiles and sleeping
in tents allowed them to enjoy nature close at hand and
tour at their own pace, with none of the restrictions of
passenger trains and railroad timetables or with the
formalities, expenses, and impersonality of hotels.
(A) with none of the restrictions of passenger trains
and railroad timetables or with the
(B) with none of the restrictions of passenger trains,
railroad timetables, nor
(C) without the restrictions of passenger trains and
railroad timetables nor
(D) without the restrictions of passenger trains and
railroad timetables or with the
(E) without the restrictions of passenger trains and
railroad timetables or the
Rhetorical construction; Diction
e sentence lays out some advantages that car
travel and tent camping were perceived to o er
over rail travel. e sentence attempts to describe
these advantages in terms of the absence of any of
a series of annoyances accompanying rail travel.
But the sentence fails because of the mismatch
between with none of . . . and or with. . . . One way
to successfully convey the intended meaning is to
use the preposition without governing all the items
in the series, expressed as nouns or noun phrases.
A By using none of . . . to introduce the rst
drawback of rail travel, and or to introduce
the rest of them, this sentence suggests that
the presence of drawbacks on the nal list is
an alternative to the absence of restrictions .
B With none . . . nor . . . is nonidiomatic (as
opposed to neither . . . nor . . . ).
C e structure without . . . nor . . . in the way
used here is nonidiomatic. e negative
without governs the whole list of drawbacks
at the end of the sentence.
D e coupling of without and or with is
confusing, suggesting, as in (A), that the
drawbacks on the nal list are an alternative
to the absence of restrictions .
E Correct. e sentence is unambiguous and
constructed in a way that without clearly
distributes over all the items in the series.
e correct answer is E.
714. Over the next few years, increasing demands on the
Chattahoochee River, which ows into the Apalachicola
River, could alter the saline content of Apalachicola
Bay, which would rob the oysters there of their avor,
and to make them decrease in size, less distinctive,
and less in demand.
(A) which would rob the oysters there of their avor,
and to make them decrease in size,
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(B) and it would rob the oysters there of their avor,
make them smaller,
(C) and rob the oysters there of their avor, making
them decrease in size,
(D) robbing the oysters there of their avor and
making them smaller,
(E) robbing the oysters there of their avor, and
making them decrease in size,
The sentence claims that demands for river water may
change the saline content of the bay, possibly altering
the avor and size of oysters there and diminishing the
oysters’ marketability. The sentence is not parallel. It
should read which would rob the oysters . . . and make
them decrease to be parallel and grammatical. The series
of three phrases after make them that describes what will
happen to the oysters also needs to be parallel.
A e referent of the relative pronoun, which ,
is ambiguous; the two e ects of altered
saline content are not expressed in parallel
form, with a relative clause expressing
the rst e ect, and an in nitive phrase
expressing the second.
B e referent of the pronoun it is ambiguous.
Also, the e ects of the bay’s altered saline
content are not expressed in parallel form—
the rst being an independent clause and
the second a verb phrase.
C e comma before the conjunction and
signals that an independent clause will
follow and , but a verb phrase follows
instead. e series of phrases following
making them lacks appropriate parallelism.
D Correct. e potential e ects on the oysters
are expressed by two parallel participial
phrases, the second of which lists three
adjectives correctly in a series.
E e series of phrases following making them
lacks appropriate parallelism.
e correct answer is D.
715. Elizabeth Barber, the author of both Prehistoric Textiles ,
a comprehensive work on cloth in the early cultures
of the Mediterranean, and also of Women’s Work , a
more general account of early cloth manufacture, is an
expert authority on textiles in ancient societies.
(A) also of Women’s Work , a more general account of
early cloth manufacture, is an expert authority on
(B) also Women’s Work , a more general account of
cloth manufacture, is an expert authority about
(C) of Women’s Work , a more general account about
early cloth manufacture, is an authority on
(D) of Women’s Work , a more general account about
early cloth manufacture, is an expert authority
about
(E) Women’s Work , a more general account of early
cloth manufacture, is an authority on
Rhetorical construction; Idiom; Parallelism
Using a lot of parenthetical elements, this
sentence communicates the main idea that
Elizabeth Barber is an authority on textiles in
ancient societies. It is the main rhetorical goal
of the sentence to position the parenthetical
elements so that they do not obscure the main
idea. e parenthetical descriptions need to be
streamlined enough to be informative, but not too
long. In addition, several versions repeat of before
the title Women’s Work and doing so makes the
sentence unparallel; the rst of comes before both
and so should distribute over both clauses.
A e use of also of before Women’s Work is
redundant and unparallel. It is su cient to
connect the two book titles like this: both X
and Y . e meanings of the two nouns expert
and authority largely overlap, so there is no
need to modify one with the other.
B e use of also before Women’s Work is
redundant. It is su cient to connect the
two book titles like this: both X and Y . e
meanings of the two nouns expert and
authority largely overlap, so there is no need to
modify one with the other. Finally, the noun
authority takes the preposition on , not about .
C As in (A), repeating the preposition of
before Women’s Work makes the sentence
unparallel. e noun account takes the
preposition of , not about .
D As in (A) and (C), repeating the preposition
of before Women’s Work makes the sentence
unparallel. e noun account takes the
preposition of , not about
. It is redundant to
modify authority with expert because they
express the same idea. Finally, the noun
authority takes the preposition on , not about .
9.8 Sentence Correction Answer Explanations
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E Correct. is version is parallel, uses the
most concise structure of the parenthetical
descriptions, eschews the redundant
modi cation of authority , and employs the
correct prepositions.
e correct answer is E.
716. Digging in sediments in northern China, evidence
has been gathered by scientists suggesting that
complex life‐forms emerged much earlier than they had
previously thought.
(A) evidence has been gathered by scientists
suggesting that complex life‐forms emerged
much earlier than they had
(B) evidence gathered by scientists suggests a
much earlier emergence of complex life‐forms
than had been
(C) scientists have gathered evidence suggesting
that complex life‐forms emerged much earlier
than
(D) scientists have gathered evidence that suggests
a much earlier emergence of complex life‐forms
than that which was
(E) scientists have gathered evidence which
suggests a much earlier emergence of complex
life‐forms than that
Logical predication; Modifi cation
In principle, the relationship described in the rst
part of the underlined portion could be expressed
with scientists as the subject ( scientists gathered
evidence ) or with evidence as the subject ( evidence
was gathered by scientists ). e latter construction
could be e ective in some contexts, but here its
relationship to the rest of the sentence appears to
commit the writer to the claim that the evidence
was digging in China.
A is version has a dangling participle,
digging. … Digging in sediments in northern
China must modify scientists , not evidence .
e passive structure of the main clause also
creates an inadvisable distance between the
words evidence and suggesting . Furthermore,
the dependent clause starting with
suggesting may be construed with either the
evidence or the scientists, which makes this
version unnecessarily ambiguous.
B is version has a dangling participle,
digging. … Digging in sediments in northern
China must modify scientists , not evidence .
C Correct. Choosing scientists as the subject
of gathered , this version corrects the
dangling participle. It also uses a parallel
active form of the verb emerge , and does not
use redundant material.
D In this context it would be preferable to use
a verb ( emerged ). e phrasing used here
( suggests a much earlier emergence of ) sounds
more stilted and is less clear and direct.
In addition, inserting that which before
previously thought is not only redundant but
incorrect English.
E e problems described in (D) above are
also in evidence here.
e correct answer is C.
717. Employing many different techniques throughout his
career, Michelangelo produced a great variety of art
works, including paintings, for example, in the Sistine
Chapel, to sculpture, for example, the statue of David.
(A) including paintings, for example, in the Sistine
Chapel, to sculpture, for example,
(B) including paintings, for example, in the Sistine
Chapel, to sculpture, like
(C) including paintings, such as those in the Sistine
Chapel, and sculpture, as
(D) ranging from paintings, such as those in the
Sistine Chapel, to sculpture, such as
(E) ranging from paintings, such as in the Sistine
Chapel, and sculpture, such as
Parallelism; Rhetorical construction
is sentence names painting and sculpture
as two of the many kinds of art created by
Michelangelo and provides examples of his work
in those two art forms. Although the two sets
of examples are expressed in parallel form, the
position of the phrase for example that introduces
them creates a choppy and awkward sentence
since it must be surrounded by commas. A more
concise way to construct parallel sets of examples
is to express each using a phrase introduced by
such as.
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A e sentence is choppy and awkward due
to the twofold use of the phrase for example,
which must be surrounded by commas. e
preposition to, in context, suggests a range,
but it would then be needed to be preceded
by from.
B e examples of art are not in parallel form
since the rst is introduced by for example
followed by the prepositional phrase in the
Sistine Chapel, and the second is introduced
by the prepositional phrase like... e
preposition to is unidiomatic and awkwardly
used here.
C e examples of art are not in parallel form
since the rst is introduced by such as, and
the second is introduced by as.
D Correct. e examples of art are in parallel
form, each introduced with the words such
as.
E Although the examples of art are both
introduced by such as, the form is not
parallel since the rst is a prepositional
phrase (in the Sistine Chapel) and the second
is a noun phrase (the statue of David).
e correct answer is D.
718. Outlining his strategy for nursing the troubled
conglomerate back to health, the chief executive’s
plans were announced on Wednesday for cutting the
company’s huge debt by selling nearly $12 billion in
assets over the next 18 months.
(A) executive’s plans were announced on Wednesday
for cutting the company’s huge debt by selling
nearly $12 billion in assets over the next
18 months
(B) executive’s plans, which are to cut the company’s
huge debt by selling nearly $12 billion in assets
over the next 18 months, were announced on
Wednesday
(C) executive’s plans for cutting the company’s huge
debt by selling nearly $12 billion in assets over the
next 18 months were announced on Wednesday
(D) executive announced plans Wednesday to cut the
company’s huge debt by selling nearly $12 billion
in assets over the next 18 months
(E) executive announced plans Wednesday that are
to cut the company’s huge debt by selling nearly
$12 billion in assets over the next 18 months
Logical predication; Verb form
In this sentence, the opening dependent clause
beginning Outlining his strategy is a dangling
modi er. Furthermore, the verb form for
announce should make it clear that the chief
executive is doing the announcing. In addition,
to cut is a clearer phrase than for cutting in this
sentence.
A e subject of the opening clause should be
executive , not plans . e passive verb form
were announced suggests that someone other
than the chief executive is outlining the
strategy. Putting the phrase were announced
between plans and for cutting makes it
somewhat unclear whether for cutting … is
intended to modify announced or plans .
B In addition to having a dangling modi er
and the wrong form of the verb announce ,
this sentence is made less clear by separating
the subject and verb with the long clause
beginning with which are .
C is version has the same issues as in (A)
and (B) and is made less clear by separating
the subject and verb with the long clause
beginning with for cutting .
D Correct. e opening clause properly
modi es chief executive and the verb form
announced makes it clear that the chief
executive is doing the announcing.
E Although the opening clause correctly
modi es chief executive in this version,
the words that are are extraneous and also
suggest that the plans themselves are doing
the cutting and selling.
e correct answer is D.
719. It is called a sea, but the landlocked Caspian is actually
the largest lake on Earth, which covers more than four
times the surface area of its closest rival in size, North
America’s Lake Superior.
(A) It is called a sea, but the landlocked Caspian is
actually the largest lake on Earth, which covers
(B) Although it is called a sea, actually the
landlocked Caspian is the largest lake on Earth,
which covers
(C) Though called a sea, the landlocked Caspian is
actually the largest lake on Earth, covering
9.8 Sentence Correction Answer Explanations
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(D) Though called a sea but it actually is the largest
lake on Earth, the landlocked Caspian covers
(E) Despite being called a sea, the largest lake
on Earth is actually the landlocked Caspian,
covering
Logical predication; Grammatical
construction
e topic of this sentence is a single large body
of water, the Caspian Sea. e wording needs to
make it clear that being the largest lake on Earth and
covering more than four times the surface area of …
Lake Superior are both predicated of this one subject.
A e referent of which is unclear.
Grammatically, its antecedent cannot be
the landlocked Caspian , so it must be either
Earth or the largest lake on Earth . e latter
is a little odd, because the sentence has
already said that the lake in question is the
Caspian, so one would expect and instead of
which . For these reasons and because Earth
immediately precedes which , the sentence
appears to say, illogically, that Earth covers
more than four times the surface area of
Lake Superior.
B As in (A), this appears to say, illogically,
that Earth covers more than four times the
surface area of Lake Superior.
C Correct. e wording is direct,
unambiguous, and grammatically correct.
D e structure here is grammatically incoherent.
E Despite being called a sea indicates, somewhat
illogically, that the largest lake being called a
sea would lead one to expect it not to be the
Caspian. is makes little sense, especially
to those who are familiar with the name
Caspian Sea .
e correct answer is C.
720. Neuroscientists, having amassed a wealth of
knowledge over the past twenty years about the brain
and its development from birth to adulthood, are now
drawing solid conclusions about how the human brain
grows and how babies acquire language.
(A) Neuroscientists, having amassed a wealth of
knowledge over the past twenty years about
the brain and its development from birth to
adulthood, are
(B) Neuroscientists, having amassed a wealth of
knowledge about the brain and its development
from birth to adulthood over the past twenty
years, and are
(C) Neuroscientists amassing a wealth of knowledge
about the brain and its development from birth to
adulthood over the past twenty years, and are
(D) Neuroscientists have amassed a wealth of
knowledge over the past twenty years about
the brain and its development from birth to
adulthood,
(E) Neuroscientists have amassed, over the past
twenty years, a wealth of knowledge about
the brain and its development from birth to
adulthood,
Grammatical construction; Logical
predication
is sentence introduces the subject
( Neuroscientists ), pauses to explain what
neuroscientists have accomplished in the past
twenty years, and then concludes by explaining
what neuroscientists are presently doing as
a result of their past accomplishments. e
second part of the sentence—the explanation—
interrupts the ow of the sentence from the
subject ( Neuroscientists ) to the predicate ( are
now drawing solid conclusions …); it should
therefore be bracketed by commas. e sentence
construction should provide a main verb for the
subject neuroscientists .
A Correct. e explanatory phrase between
the subject and predicate is set o by
commas, and the main clause contains
both a subject ( Neuroscientists ) and a
corresponding verb ( are now drawing ).
B And are indicates that are follows a previous
verb, but in fact the sentence has not yet
provided a rst main verb for the subject
Neuroscientists ; the sentence is therefore
incomplete; over the … years appears to be
modifying adulthood .
C Amassing, like having amassed , functions
as an adjective, not a verb; the sentence
therefore lacks the rst main verb implied
by the compound verb construction and are
now drawing. …
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D e nal descriptor in present tense, now
drawing conclusions … does not t the
opening clause, which is in present‐perfect
tense ( have amassed a wealth … ) and seems
to modify adulthood .
E Like (D), this sentence attempts to attach a
present‐tense descriptor to a present‐perfect
clause.
e correct answer is A.
721. According to a recent study of consumer spending on
prescription medications, increases in the sales of the
50 drugs that were advertised most heavily accounts
for almost half of the $20.8 billion increase in drug
spending last year, the remainder of which came
from sales of the 9,850 prescription medicines that
companies did not advertise or advertised very little.
(A) heavily accounts for almost half of the $20.8
billion increase in drug spending last year, the
remainder of which came
(B) heavily were what accounted for almost half of
the $20.8 billion increase in drug spending last
year; the remainder of the increase coming
(C) heavily accounted for almost half of the $20.8
billion increase in drug spending last year, the
remainder of the increase coming
(D) heavily, accounting for almost half of the $20.8
billion increase in drug spending last year, while
the remainder of the increase came
(E) heavily, which accounted for almost half of the
$20.8 billion increase in drug spending last year,
with the remainder of it coming
Grammatical construction; Verb form
e sentence indicates that according to research,
increases in sales of the relatively small number
of the most heavily advertised drugs accounted
for nearly half of last year’s total increase in drug
spending. e sentence is awed because of
subject‐verb disagreement, and an ambiguity in
the referent of which .
A e singular verb form accounts fails to agree
in number with the plural subject increases .
What the relative pronoun which refers to is
unclear; to make clear sense, it should refer
to the . . . increase .
B e phrase were what accounted is
unnecessarily wordy; the semicolon before
the remainder signals that a complete
clause will follow, but what follows is not a
complete clause.
C Correct. e sentence is clear and
grammatically correct. e subject and verb
agree.
D In the resulting sentence, no main verb
follows the main subject increases .
E e resulting sentence lacks a main verb for
the main subject increases .
e correct answer is C.
722. Along the major rivers that traverse the deserts of
northeast Africa, the Middle East, and northwest India,
the combination of a reliable supply of water and good
growing conditions both encouraged farming traditions
that, in places, endure in at least 6,000 years.
(A) good growing conditions both encouraged
farming traditions that, in places, endure in
(B) good growing conditions encouraged farming
traditions that have, in places, endured for
(C) of good growing conditions have encouraged
farming traditions that, in places, endured for
(D) of good growing conditions both encouraged
farming traditions that have, in places, endured
(E) of good growing conditions encouraged farming
traditions that have, in places, been enduring for
Logical predication; Rhetorical construction
e time line of this sentence, captured by the
use of verb tenses, is of utmost importance. A
combination of factors (in the past) encouraged
farming traditions that are still with us today. e
conditions for the use of the present perfect tense
have endured are in place.
A e word both repeats the meaning of
combination and is thus redundant. e use
of the present tense ( endure ) is not justi ed
by the time line of the whole sentence.
e correct preposition for this type of
construction is for (an amount of time), not in .
B Correct. is version correctly employs the
present perfect tense with the appropriate
adverbial for at least 6,000 years .
9.8 Sentence Correction Answer Explanations
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C e repetition of the preposition of before
good growing conditions makes no sense.
It seems to indicate that there is both a
combination of a reliable supply of water and
a combination of good growing conditions.
D e preposition of should not be repeated in
front of good growing conditions . e word
both repeats the meaning of combination and
is thus redundant.
E e preposition of should not be repeated
in front of good growing conditions . e use
of the present perfect progressive have been
enduring is not grammatically incorrect, but
it is rhetorically inappropriate and sounds
exaggerated.
e correct answer is B.
723. Despite its covering the entire planet, Earth has a
crust that is not seamless or stationary, rather it is
fragmented into mobile semirigid plates.
(A) Despite its covering the entire planet, Earth has
a crust that is not seamless or stationary, rather
it is
(B) Despite the fact that it covers the entire planet,
Earth’s crust is neither seamless nor is it
stationary, but is
(C) Despite covering the entire planet, Earth’s crust
is neither seamless nor is it stationary, but rather
(D) Although it covers the entire planet, Earth’s crust
is neither seamless nor stationary, but rather
(E) Although covering the entire planet, Earth has a
crust that is not seamless or stationary, but
Idiom; Parallelism; Logical predication
A dangling modi er is an error in sentence
structure whereby a participle is associated with
a word other than the one intended or with no
particular word at all. In this sentence, Earth is
the closest word to the participial clause, and so
the latter means that Earth is covering the entire
planet (itself ), which is a contradiction.
A is version has a dangling participle.
e addition of it is before fragmented
is unwarranted and makes the sentence
ungrammatical. Neither … nor … but rather
would make the intended relationship among
seamless , stationary , and fragmented clearer
and more precise than not … or … rather .
B Parallel structure is disrupted by the
addition of is it after nor and by the addition
of is after but .
C Parallel structure is disrupted by the
addition of is it after nor .
D Correct. Despite and although are very close
in meaning. However, despite is a preposition
and needs to be followed by a noun or noun
phrase, while although is a conjunction and
should be followed by a nite clause. is
version uses although correctly. e parallel
structure is also clear and correct.
E Although is a conjunction and should be
followed by a nite clause with a subject, not
by a participle. In addition, the rst clause
represents a dangling modi er. Omitting
rather from the parallel structure neither X
nor Y but rather Z is possible, but not optimal.
e correct answer is D.
724. Emily Dickinson’s letters to Susan Huntington Dickinson
were written over a period beginning a few years
before Susan’s marriage to Emily’s brother and ending
shortly before Emily’s death in 1886, outnumbering her
letters to anyone else.
(A) Dickinson were written over a period beginning
a few years before Susan’s marriage to Emily’s
brother and ending shortly before Emily’s death
in 1886, outnumbering
(B) Dickinson were written over a period that begins
a few years before Susan’s marriage to Emily’s
brother and ended shortly before Emily’s death in
1886, outnumber
(C) Dickinson, written over a period beginning a few
years before Susan’s marriage to Emily’s brother
and that ends shortly before Emily’s death in
1886 and outnumbering
(D) Dickinson, which were written over a period
beginning a few years before Susan’s marriage
to Emily’s brother, ending shortly before Emily’s
death in 1886, and outnumbering
(E) Dickinson, which were written over a period
beginning a few years before Susan’s marriage
to Emily’s brother and ending shortly before
Emily’s death in 1886, outnumber
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Parallelism; Grammatical construction
e main point of the sentence is that
Dickinson’s letters to her sister‐in‐law outnumber
her letters to anyone else. To emphasize this
point, outnumber should be the main verb, and the
description introduced by the passive verb were
written needs to be changed from a main clause
to an adjectival phrase.
A e long, wordy opening clause gives
too much emphasis to the period when
Dickinson’s letters were written; it is unclear
what outnumbering refers to.
B e verbs describing the letter‐writing
period ( begins and ended ) are not parallel.
C e verbs describing the letter‐writing
period need to be in parallel form and agree
in tense—e.g., beginning and ending or that
began and that ended ; this is a fragment
because it lacks a main verb for letters .
D e lack of a main verb for the subject of
the sentence, letters , makes this a fragment.
E Correct. e information about the period
when Dickinson’s letters were written is
contained in an adjectival phrase set o by
commas, and the main verb outnumber refers
clearly to letters .
e correct answer is E.
725. At the end of 2001, motion picture industry
representatives said that there were about a million
copies of Hollywood movies available online and
expected piracy to increase with high‐speed Internet
connections that become more widely available .
(A) online and expected piracy to increase with high‐
speed Internet connections that become more
widely available
(B) online and expect the increase of piracy with
the wider availability of high‐speed Internet
connections
(C) online, and they expect more piracy to increase
with the wider availability of high‐speed Internet
connections
(D) online, and that they expected the increase of
piracy as high‐speed Internet connections would
become more widely available
(E) online, and that they expected piracy to increase
as high‐speed Internet connections became
more widely available
Rhetorical construction; Grammatical
construction
Every clause needs a subject, either an overt
subject or an understood subject (whose
interpretation can come from a coordinated clause
or some other nearby clause). In this sentence, the
clause containing expected lacks a clear subject.
e intended subject is motion picture industry
representatives , but to clearly indicate that, the
subject should either be repeated or be replaced
with the pronoun they . Furthermore, piracy to
increase with high‐speed Internet connections that
become more widely available is awkward, and it
fails to clearly communicate the idea that piracy
will increase as a result of high‐speed Internet
connections becoming available.
A e second clause is awkward and unclear;
there is no clear subject for expected .
B ere is no clear subject for expect .
C It is redundant to use both more and increase .
D is wording makes the meaning very
unclear. ey expected the increase in
piracy appears to refer to a particular
(past) increase, but this does not clearly
make sense with the ensuing use of the
conditional verb form would become , which
is inappropriate here.
E Correct. In this version the verb expect
has an overt subject, and the following
phrasing clearly indicates that the expected
increase in piracy is the result of high‐speed
Internet connections becoming more widely
available.
e correct answer is E.
726. Making things even more dif cult has been general
market inactivity lately, if not paralysis, which has
provided little in the way of pricing guidance.
(A) has been general market inactivity lately, if not
paralysis, which has provided
(B) there is general market inactivity, if not paralysis,
lately it has provided
(C) general market inactivity, if not paralysis, has
lately provided
9.8 Sentence Correction Answer Explanations
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(D) lately, general market inactivity, if not paralysis,
has provided
(E) is that lately general market inactivity, if not
paralysis, which provides
Grammatical construction; Rhetorical
construction
is sentence uses a special inverted structure,
putting the predicate ( Making things even more
di cult ) before the verb ( has been ) and the
subject. In this construction, the subject ( general
market inactivity ) can be directly compared with
paralysis . Such contrasts are best made using
phrases that are adjacent, not separated by other
material (here, the adverb lately ). If a more
normal clause structure is used, making things
even more di cult becomes a modi er, not the
main predicate, so it should be clearly set o from
the rest of the clause with a comma.
A is inverted structure makes general market
activity the subject of Making things even
more di cult . is would be legitimate
by itself, but it requires general market
inactivity to be next to both if not paralysis
(for contrast) and which (marking a relative
clause modifying inactivity ). It cannot be
next to both of these simultaneously.
B is is a run‐on sentence, with two
independent clauses (Making things
even more di cult there is general market
inactivity, if not paralysis, and lately it has
provided little in the way of pricing guidance)
conjoined merely by a comma, rather than
by a coordinating conjunction, such as and.
Also, the initial topic phrase (Making things
even more di cult) is awkward without a
following comma.
C e initial topic phrase (Making things
even more di cult ) should be followed by a
comma.
D Correct. e topic phrase (Making things
even more di cult ) is properly separated
from the subject by a comma, and inactivity
and if not paralysis are adjacent for the
clearest connection between them.
E is is a sentence fragment.
e correct answer is D.
727. Unlike the conviction held by many of her colleagues
that genes were relatively simple and static, Barbara
McClintock adhered to her own more complicated
ideas about how genes might operate, and in 1983,
at the age of 81, was awarded a Nobel Prize for her
discovery that the genes in corn are capable of moving
from one chromosomal site to another.
(A) Unlike the conviction held by many of her
colleagues that genes were
(B) Although many of her colleagues were of the
conviction of genes being
(C) Contrary to many of her colleagues being
convinced that genes were
(D) Even though many of her colleagues were
convinced that genes were
(E) Even with many of her colleagues convinced of
genes being
Rhetorical construction; Idiom; Logical
predication
e sentence compares a widely held conviction
about genes with McClintock’s adherence to her
own ideas, then goes on to describe McClintock’s
accomplishments. e sentence must not compare
widespread convictions with McClintock herself.
e clearest and most e cient way to make
the comparison is to introduce McClintock’s
colleagues’ convictions in a dependent clause,
followed by a main clause that introduces
McClintock’s di erent way of doing things and
goes on to explain how successful she was.
A Incorrect comparison between conviction
and Barbara McClintock .
B Were of the conviction of genes being relatively
simple is wordy and awkward.
C Contrary to many of her colleagues being
convinced is wordy and awkward.
D Correct. A dependent clause describing
the beliefs of McClintock’s colleagues is
followed by the main clause presenting the
contrasting beliefs of McClintock.
E Even with many of her colleagues … is wordy
and indirect.
e correct answer is D.
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728. Ryu
–
nosuke Akutagawa’s knowledge of the literatures of
Europe, China, and that of Japan were instrumental in
his development as a writer, informing his literary style
as much as the content of his ction.
(A) that of Japan were instrumental in his development
as a writer, informing his literary style as much as
(B) that of Japan was instrumental in his
development as a writer, and it informed both his
literary style as well as
(C) Japan was instrumental in his development as a
writer, informing both his literary style and
(D) Japan was instrumental in his development as a
writer, as it informed his literary style as much as
(E) Japan were instrumental in his development
as a writer, informing both his literary style in
addition to
Logical predication; Agreement
When a verb follows a complex noun phrase made
up of several parts, it agrees with the rst noun in
the phrase. In this case, knowledge of the literatures
of Europe, China, and Japan is a singular noun and
the correct verb form is was , not were . e various
parts of an enumeration have to be alike: the
literatures of Europe, China, and Japan. e logical
relationship between the predicates is important.
A is version of the sentence violates the
correct subject‐verb agreement, and the
correct structure of enumeration is disrupted
by the addition of that of in front of Japan .
B e correct structure of enumeration is
disrupted by the addition of that of in front of
Japan . Both … as well as … is incorrect usage.
C Correct. e structure of the enumeration
( Europe, China, and Japan ) as well as the
conjunction structure ( both X and Y ) are
correct. e logical relationships among the
parts of the sentence are clearly expressed.
D is phrasing makes it unclear what the
writer is claiming. It appears to indicate that
the e ect of Akutagawa’s knowledge on his
development as a writer was due to the fact
that both of the aspects of his writing were
in uenced to the same extent. However, it is
implausible to suppose that this is what the
writer intends. Furthermore, the comparison
is ambiguous: did his knowledge inform his
style as much as it informed the content,
or did it inform his style as much as the
content informed his style?
E e subject‐verb agreement in this version is
incorrect. Both X in addition to Y is incorrect
usage.
e correct answer is C.
729. According to scientists who monitored its path,
an expanding cloud of energized particles ejected
from the Sun recently triggered a large storm in the
magnetic eld that surrounds Earth, which brightened
the Northern Lights and also possibly knocking out a
communications satellite.
(A) an expanding cloud of energized particles
ejected from the Sun recently triggered a large
storm in the magnetic eld that surrounds Earth,
which brightened the Northern Lights and also
possibly knocking
(B) an expanding cloud of energized particles
ejected from the Sun was what recently
triggered a large storm in the magnetic eld that
surrounds Earth, and it brightened the Northern
Lights and also possibly knocked
(C) an expanding cloud of energized particles
ejected from the Sun recently triggered a large
storm in the magnetic eld that surrounds Earth,
brightening the Northern Lights and possibly
knocking
(D) a large storm in the magnetic eld that surrounds
Earth, recently triggered by an expanding cloud
of energized particles, brightened the Northern
Lights and it possibly knocked
(E) a large storm in the magnetic eld surrounding
Earth was recently triggered by an expanding
cloud of energized particles, brightening the
Northern Lights and it possibly knocked
Logical predication; Rhetorical
construction; Verb form
e timing and logical relationships among the
events described in this sentence are of utmost
importance. e scientists monitored a cloud
ejected from the Sun. e cloud triggered a large
storm, whose consequences were the brightening
of the Northern Lights and the possible knocking
out of a satellite. e latter two events are in a
conjunction, so they should be represented by
similar verb forms.
9.8 Sentence Correction Answer Explanations
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GMAT® Offi cial Guide 2018
A In this context, the shift in verb form from
which brightened to and also possibly knocking
is ungrammatical. e two verbs should be in
the same verb form for parallel construction.
B X was what triggered Y is wordy and
awkward, and its meaning is unclear in
this context. Given the most plausible
intended meaning of the sentence, the two
conjunctions and … and … in the last clause
are redundant. e comma after Earth
turns the nal part of the sentence into an
independent clause, and it is unclear whether
this is part of what the scientists claimed or a
separate claim made by the writer.
C Correct. e conjoined elements are of
parallel forms, and the logical relations
between the events are clear and concisely
communicated.
D e wording in this answer choice makes
the intended meaning unclear. e
information that the cloud particles were
ejected from the Sun is lost. e sentence is
ungrammatical; the second conjoined main
verb, knocked , needs no pronoun subject it
because its subject is a large storm .
E e wording in this answer choice
makes the intended meaning unclear.
e information that the cloud particles
were ejected from the Sun is lost. e
two conjoined verbs are of di erent form;
the second conjoined verb includes an
unnecessary pronoun subject.
e correct answer is C.
730. In 1850, Lucretia Mott published her Discourse on
Women , arguing in a treatise for women to have equal
political and legal rights and for changes in the married
women’s property laws.
(A) arguing in a treatise for women to have equal
political and legal rights
(B) arguing in a treatise for equal political and legal
rights for women
(C) a treatise that advocates women’s equal political
and legal rights
(D) a treatise advocating women’s equal political and
legal rights
(E) a treatise that argued for equal political and legal
rights for women
Parallelism; Rhetorical construction
Mott’s Discourse was a treatise, and it is redundant
and confusing to present her as both publishing
her Discourse and arguing in a treatise, as though
they were two separate things. e verb arguing
must be followed by a prepositional phrase
beginning with for , but the verb advocating simply
takes a direct object.
A After published her Discourse … arguing in a
treatise is wordy and imprecise.
B Arguing in a treatise is redundant and awkward.
C e verb advocates does not work
idiomatically with the prepositional phrase
for changes. …
D e verbal advocating does not work
idiomatically with the prepositional phrase
for changes. …
E Correct. e title of Mott’s publication is
followed by a phrase describing the treatise,
and argued is followed by for.
e correct answer is E.
731. To develop more accurate population forecasts,
demographers have to know a great deal more than now
about the social and economic determinants of fertility.
(A) have to know a great deal more than now about
the social and economic
(B) have to know a great deal more than they do
now about the social and economical
(C) would have to know a great deal more than they
do now about the social and economical
(D) would have to know a great deal more than they
do now about the social and economic
(E) would have to know a great deal more than now
about the social and economic
Verb form; Logical predication
is sentence explains a hypothetical situation
and therefore calls for a conditional—or contrary‐
to‐fact—construction, because in order to more
accurately predict population, demographers
would have to know more than they presently
know. A present‐tense verb is required to describe
the current state of demographers’ knowledge, and
the comparison made by the sentence must be
between current and conditional knowledge, not
between knowledge and time of knowing ( now ).
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A Wrong comparison—between knowledge
and time ( now ); conditional verb is
needed.
B Conditional verb is needed; economical is the
wrong adjective.
C Economical is the wrong adjective.
D Correct. Conditional knowledge, indicated
by would have to know , is correctly compared
to current knowledge.
E Wrong comparison—between what
demographers need to know and now .
e correct answer is D.
732. Laos has a land area about the same as Great Britain
but only four million in population, where many are
members of hill tribes ensconced in the virtually
inaccessible mountain valleys of the north.
(A) about the same as Great Britain but only four
million in population, where many
(B) of about the same size as Great Britain is, but
in Laos there is a population of only four million,
and many
(C) that is about the same size as Great Britain’s
land area, but in Laos with a population of only
four million people, many of them
(D) comparable to the size of Great Britain, but only
four million in population, and many
(E) comparable to that of Great Britain but a
population of only four million people, many of
whom
Logical predication; Grammatical
construction
e comparison in this sentence is between the
land area of Laos and the land area of Great
Britain, not between the land area of Laos and
Great Britain. e phrase about the population
of Laos is most clearly and e ciently expressed
in an appositive using a relative pronoun
to refer back to people rather than the more
abstract population . Using this construction
keeps the appropriate emphasis on the two
main claims being made about Laos, one
describing its land area and the other its sparse
population.
A e comparison between land area and
Great Britain is incorrect; where is an
inappropriate referent to population , which
does not designate a place.
B Inappropriate comparison between land
area and Great Britain; the there is …
construction is wordy and imprecise.
C e reference of them is unclear and the
expression is generally awkward.
D e coordinating conjunction and gives
undue emphasis to the claim that many of
the people in Laos live in inaccessible places.
E Correct. e land area of Laos is correctly
compared to that of Great Britain; whom
refers appropriately to people.
e correct answer is E.
733. Having been named for a mythological nymph who
cared for the infant Jupiter, the asteroid named Ida, in
the middle of the belt of asteroids that orbit the Sun
between Mars and Jupiter, was discovered in 1884.
(A) Having been named for a mythological nymph
who cared for the infant Jupiter, the asteroid
named Ida, in the middle of the belt of asteroids
that orbit the Sun between Mars and Jupiter, was
discovered in 1884.
(B) Discovered in 1884, the asteroid Ida, named for
a mythological nymph who cared for the infant
Jupiter, is in the middle of the belt of asteroids
that orbit the Sun between Mars and Jupiter.
(C) In the middle of the belt of asteroids that orbit
the Sun between Mars and Jupiter, the asteroid
Ida, discovered in 1884 and named for a
mythological nymph who cared for the infant
Jupiter.
(D) The asteroid Ida, named for a mythological
nymph who cared for the infant Jupiter and
discovered in 1884, is in the middle of the belt
of asteroids to orbit the Sun between Mars and
Jupiter.
(E) Ida, an asteroid discovered in 1884 and which
was named for a mythological nymph who cared
for the infant Jupiter, is in the middle of the belt
of asteroids to orbit the Sun between Mars and
Jupiter
9.8 Sentence Correction Answer Explanations
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GMAT® Offi cial Guide 2018
Rhetorical construction; Logical
predication; Grammatical construction
is sentence describes a discovery that
occurred in 1884 and provides some additional
information about the object that was discovered.
e most e ectively worded answer choice opens
with a past‐participial phrase ( discovered . . . )
describing the subject of the sentence, the asteroid
Ida . Ida’s discovery is logically prior to its naming,
described in a second past, following the subject
( named . . .) . e sentence is then completed with
a present tense linking verb is + prepositional
phrase to explain Ida’s location.
A Opening with a past perfect passive verb,
Having been named, this version of the
sentence illogically suggests that being
named for a mythological nymph preceded
the discovery of Ida.
B Correct. is version is clear, logically
coherent, and grammatically correct.
C is version of the sentence is
ungrammatical; it has no main verb for the
subject the asteroid Ida .
D e sequence of events is obscured by the
placement of named before discovered in the
compound participial phrases. e in nitive
form to orbit is ungrammatical in place of
the relative clause.
E is sentence awkwardly attempts to use a
compound conjunction and to join the past
participial phrase discovered in 1884 with
the relative clause which was named. . . . e
in nitive form to orbit is ungrammatical in
place of the relative clause.
e correct answer is B.
734. In ancient Thailand, much of the local artisans’ creative
energy was expended for the creation of Buddha
images and when they constructed and decorated the
temples that enshrined them.
(A) much of the local artisans’ creative energy was
expended for the creation of Buddha images
and when they constructed and decorated the
temples that enshrined them
(B) much of the local artisans’ creative energy was
expended on the creation of Buddha images and
on construction and decoration of the temples in
which they were enshrined
(C) much of the local artisans’ creative energy was
expended on the creation of Buddha images
as well as constructing and decoration of the
temples in which they were enshrined
(D) creating images of Buddha accounted for much
of the local artisans’ creative energy, and also
constructing and decorating the temples enshrining
them
(E) the creation of Buddha images accounted for
much of the local artisans’ creative energy
as well as construction and decoration of the
temples that enshrined them
Idiom; Parallelism; Rhetorical construction
e main point of the sentence is that artisans
in ancient ailand spent most of their creative
energy on three tasks: creating Buddha images,
and constructing and decorating temples to
enshrine the Buddhas. ese three tasks must
be described in parallel forms. e verb expended
should be followed by the preposition on , not for.
A For is the wrong preposition; the and when
… clause introduces faulty parallelism; it is
unclear what they refers to.
B Correct. e three activities are presented
in parallel form: creation of Buddha images
and construction and decoration of the temples.
C Constructing violates the parallelism
otherwise maintained by creation and
decoration .
D e and also phrase is awkwardly set apart
from the main claim of the sentence—
which is that all three tasks consumed much
of the artisans’ energy.
E is construction is awkward and
unnecessarily wordy and says something
di erent—that the images accounted for the
construction and decoration of temples.
e correct answer is B.
735. The English physician Edward Jenner found that if
experimental subjects were deliberately infected with
cowpox, which caused only a mild illness, they are
immune from smallpox.
(A) which caused only a mild illness, they are
immune from
(B) causing only a mild illness, they become immune
from
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(C) which causes only a mild illness, they are
immune to
(D) causing only a mild illness, they became immune
from
(E) which caused only a mild illness, they would
become immune to
Verb form
is sentence describes the result of infecting
volunteers with cowpox. A conditional verb
form is used to describe the cowpox infection: if
experimental subjects were deliberately infected. e
sentence then incorrectly uses simple present tense
for the e ects of that infection: they are immune.
However, since the e ects are dependent on an
action that may or may not occur, the correct
way to express those e ects is by using another
conditional verb form: they would become immune.
A e e ects of a conditional situation are
incorrectly expressed using the simple
present tense verb are.
B e participle causing suggests that infecting
the subjects with cowpox caused a mild
illness only in some of the cases—but this
does not seem to be the intended meaning.
e e ects of a conditional situation are
incorrectly expressed using the simple present
tense verb become. e preposition from is
incorrect with immune; it should be to.
C e e ects of a conditional situation are
incorrectly expressed using the simple
present tense verb are.
D See above the comment on causing in (B).
e e ects of a conditional situation are
incorrectly expressed using the simple past
tense verb became. e preposition with
immune should be to.
E Correct. e e ects of a conditional situation
are correctly expressed using the conditional
verb would become. e preposition to (rather
than from) is correct with immune.
e correct answer is E.
736. Covering 71 percent of Earth’s surface, the oceans
play an essential role in maintaining the conditions for
human existence on land, moderating temperature
by the absorption of heat and carbon dioxide, and
giving pure water back to the atmosphere through
evaporation.
(A) Covering 71 percent of Earth’s surface, the
oceans play an essential role in maintaining
the conditions for human existence on land,
moderating
(B) Covering 71 percent of Earth’s surface and
playing an essential role in maintaining the
conditions for human existence on land, the
oceans moderate
(C) The oceans cover 71 percent of Earth’s surface
and play an essential role in maintaining conditions
for human existence on land, and by moderating
(D) The oceans cover 71 percent of Earth’s
surface, play an essential role in maintaining
the conditions for human existence on land, and
moderate
(E) The oceans cover 71 percent of Earth’s surface,
playing an essential role in maintaining the
conditions for human existence on land, and they
moderate
Parallelism; Rhetorical construction;
Grammatical construction
is sentence about the essential role oceans play
in maintaining conditions for human existence on
land begins with a participial phrase describing
the vastness of the oceans, followed by the
main clause ( oceans play an essential role . . . ). e
object, role , is modi ed by a prepositional phrase
that indicates what kind of role the oceans play
(it plays a role in maintaining the conditions for
human existence on land ). is statement about the
ocean’s role in maintaining terrestrial conditions
is elucidated by two parallel participial phrases
that describe the oceans, explaining how they
maintain conditions essential for human existence
on land ( moderating . . . and giving . . . ).
A Correct. is version of the sentence
e ectively conveys the means by which the
ocean plays an essential role in maintaining
the conditions for human existence on land,
using parallel verb forms.
B is version of the sentence is ungrammatical;
and giving . . . suggests that this is part of a
series of participial phrases, but it is not.
C e conjunction followed by a prepositional
phrase and by moderating . . . anticipates a
new subject—an agent that does something
by moderating—but this subject never
appears.
9.8 Sentence Correction Answer Explanations
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GMAT® Offi cial Guide 2018
D is version of the sentence is structured as a
series of verbs— cover, play , and moderate —all
describing things the oceans do; the nal
participial phrase giving . . . water . . . violates
the parallel structure set up in the sentence.
E is version of the sentence correctly makes
playing an essential role . . . a function of
the oceans’ coverage of Earth’s surface,
but the introduction of a new main verb
moderate fails to indicate that what follows
(moderating temperature and returning
pure water) identi es the role oceans play in
maintaining conditions for human existence
on land. Furthermore, the participial phrase
and giving pure water . . . violates the parallel
structure set up by the series of main verbs
that appear earlier in this version of the
sentence.
e correct answer is A.
737. Some anthropologists believe that the genetic
homogeneity evident in the world’s people is the result
of a “population bottleneck”—at some time in the past
our ancestors suffered an event, greatly reducing their
numbers and thus our genetic variation.
(A) at some time in the past our ancestors suffered
an event, greatly reducing their numbers
(B) that at some time in the past our ancestors
suffered an event that greatly reduced their
numbers
(C) that some time in the past our ancestors
suffered an event so that their numbers were
greatly reduced,
(D) some time in the past our ancestors suffered
an event from which their numbers were greatly
reduced
(E) some time in the past, that our ancestors
suffered an event so as to reduce their numbers
greatly,
Grammatical construction; Parallelism
e underlined part of this sentence is an
explanatory rewording of the clause that follows
believe . Scientists believe that X —[in other words,]
that Y . In this construction, X and Y are parallel
clauses.
A e omission of that after the dash makes
the function of the nal clause unclear.
e structure makes that clause appear to
be an awkward and rhetorically puzzling
separate assertion that the writer has
appended to the prior claim about what the
anthropologists believe. e agent or cause
of reducing is unclear.
B Correct. Repetition of that e ectively
signals the paraphrasing of the belief.
C e preposition at before some time is
missing; without at the adverb sometime
would be needed instead of this two‐word
noun phrase. e modi er of event is
expressed with a wordy passive construction,
which destroys the parallelism between it
and what follows.
D Repetition of that signals the paraphrasing
of the belief and is therefore needed. e
preposition at before some time is missing.
e modi er of event is expressed with a
wordy passive construction, which destroys
the parallelism between it and what
follows.
E at is repeated in the paraphrase, but in
the wrong place. A possible, and absurd,
reading of this version is that our ancestors
su ered an event in order to willfully
reduce their own numbers and thus our
genetic variation.
e correct answer is B.
738. Foraging at all times of the day and night, but
interspersing their feeding with periods of rest that last
between one and eight hours, a sperm whale could eat
so much as a ton of squid a day.
(A) between one and eight hours, a sperm whale
could eat so
(B) between one and eight hours, sperm whales can
eat as
(C) between one to eight hours, sperm whales could
eat as
(D) from one to eight hours, sperm whales could eat
so
(E) from one to eight hours, a sperm whale can
eat so
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749
Agreement; Diction
Although this sentence, as presented, uses the
conditional or past verb form could , it is more
plausibly intended to make a general statement
about the actual behavior of a species, a statement
that holds in the present day. For that purpose,
the present indicative can is preferable. So much
as is not the correct wording to express the upper
level of a variable amount; as much as should
be used instead. Also, although the singular a
sperm whale can be used to refer to sperm whales
generally, the plural their needs to refer to the
plural sperm whales .
A is sentence incorrectly uses so . Also, the
plural their does not agree with the singular
sperm whale .
B Correct. Both can and as are used; also,
sperm whales agrees with the plural their .
C To is the wrong word to use with between .
e proper construction would be between . . .
and or from . . . to .
D is sentence incorrectly uses so .
E So is not the correct form; also the use of the
singular a sperm whale does not agree with
the plural their .
e correct answer is B.
739. In some types of pine tree, a thick layer of needles
protects the buds from which new growth proceeds;
consequently they are able to withstand forest res
relatively well .
(A) a thick layer of needles protects the buds from
which new growth proceeds; consequently they
are able to withstand forest res relatively well
(B) a thick needle layer protects buds from where
new growth proceeds, so that they can withstand
forest res relatively well
(C) a thick layer of needles protect the buds from
which new growth proceeds; thus, they are able
to withstand relatively well any forest res
(D) since the buds from which new growth
proceeds are protected by a thick needle layer,
consequently they can therefore withstand forest
res relatively well
(E) because the buds where new growth happens are
protected by a thick layer of needles, they are able
to withstand forest res relatively easily as a result
Grammatical construction; Rhetorical
construction
is sentence is ne as written. It uses the
correct from which to introduce the relative clause
modifying buds and avoids redundant expressions
of causation, such as consequently . . . therefore, or
because . . . as a result .
A Correct. e relative clause starting with
from which is in the correct form, and the
causality is expressed e ciently and clearly
with one word, consequently .
B In this context, needle layer is less precise
than the more standard layer of needles ,
which makes it clear that the layer is
composed of needles rather than being, for
example, a layer of a needle. From where is
not the correct form, because it is redundant
in using two words that express the idea of
location ( from and where ) instead of one.
C e short direct object any forest res is
separated from its verb withstand by an
adverb phrase; this word order is awkward,
and is acceptable only with very long direct
objects and in some cases where there is no
other reasonable way to eliminate ambiguity.
D is version is unnecessarily redundant
in expressing causation, using all of since ,
consequently , and therefore . As in answer
choice B, layer of needles would be more
precise than needle layer .
E is version is unnecessarily redundant in
expressing causation, using both because and
as a result .
e correct answer is A.
740. The tourism commission has conducted surveys of
hotels in the most popular resorts, with the ultimate
goal of reducing the guests who end up expressing
overall dissatisfaction with the service in the hotels .
(A) with the ultimate goal of reducing the guests who
end up expressing overall dissatisfaction with the
service in the hotels
(B) with the goal to ultimately reduce the number
of guests who end up expressing overall
dissatisfaction with the hotels’ service
9.8 Sentence Correction Answer Explanations
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GMAT® Offi cial Guide 2018
(C) ultimately with the goal to reduce expressions
of overall dissatisfaction by the guests with the
hotel service
(D) in an ultimate attempt to reduce the number
of guests that ends up expressing overall
dissatisfaction with the hotels’ service
(E) with the ultimate goal of reducing the number of
guests who express overall dissatisfaction with
the hotels’ service
Verb form; Rhetorical construction
is sentence seems to be saying something
absurd: that the goal is to reduce the guests
themselves, instead of to reduce the number of
guests or the expressions of dissatisfaction. It is
also awkward in introducing the super uous end
up ; but at least, if it does so, the correct form to
agree with the subject guests is end up , not ends
up , which is used in answer choice D. In general,
direct modi ers (such as with the (hotel) service )
should not be separated from the word they
modify (such as dissatisfaction ) if possible.
A Reducing the guests is clearly not the intent
of the sentence; it should be phrased as
reducing the number of guests or the
expressions of dissatisfaction.
B With the goal to ultimately reduce is awkward
and unidiomatic.
C With the hotel service should be placed next
to dissatisfaction ; also, ultimately with the
goal is awkward, better phrased as with the
ultimate goal .
D e relative clause that ends up . . . modi es
the plural guests (not, in this context,
number ), so the correct verb form is end up.
E Correct. e with phrase is concise, and
it is the number of guests, not the guests
themselves, that is to be reduced. With the
hotel’s service is adjacent to dissatisfaction .
Also, in the relative clause starting with who ,
the implicit subject of express is guests , so
this verb correctly agrees with its subject.
e correct answer is E.
741. A new study suggests that the conversational pace
of everyday life may be so brisk it hampers the ability
of some children for distinguishing discrete sounds
and words and, the result is, to make sense of
speech.
(A) it hampers the ability of some children for
distinguishing discrete sounds and words and,
the result is, to make
(B) that it hampers the ability of some children to
distinguish discrete sounds and words and, as a
result, to make
(C) that it hampers the ability of some children to
distinguish discrete sounds and words and, the
result of this, they are unable to make
(D) that it hampers the ability of some children to
distinguish discrete sounds and words, and
results in not making
(E) as to hamper the ability of some children for
distinguishing discrete sounds and words,
resulting in being unable to make
Rhetorical construction; Parallelism;
Diction
e sentence describes a hypothesized causal
series: e fast conversational pace impairs
children’s ability to distinguish individual sounds
and words, and this, in turn, impairs their ability
to make sense of speech. ese two consequences,
both impaired abilities, are most clearly and
e ciently expressed in parallel in nitive phrases
( to distinguish and to make ). e explanatory
phrase as a result before the second in nitive
clari es the sequence. e term ability should be
followed by the preposition to , not for.
A For is the wrong preposition to follow
ability ; the phrase and, the result is ,
introduces a new clause which indicates
that children’s inability to distinguish
sounds enables them to make sense of
speech.
B Correct. e two abilities hampered by the
fast pace of conversation are described with
the parallel in nitive phrases to distinguish
and to make .
C e result of this is a new subject that
grammatically requires a new verb; the
phrase is wordy and unclear.
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D is version of the sentence nonsensically
suggests that the pace of speech results in
not making sense of speech, removing the
children from the picture as the ones who
are a ected.
E e phrase is awkward, wordy, and unclear;
for is the incorrect preposition to follow ability.
e correct answer is B.
742. The nineteenth‐century chemist Humphry Davy
presented the results of his early experiments in his
“Essay on Heat and Light,” a critique of all chemistry
since Robert Boyle as well as a vision of a new
chemistry that Davy hoped to found.
(A) a critique of all chemistry since Robert Boyle as
well as a vision of a
(B) a critique of all chemistry following Robert Boyle
and also his envisioning of a
(C) a critique of all chemistry after Robert Boyle and
envisioning as well
(D) critiquing all chemistry from Robert Boyle
forward and also a vision of
(E) critiquing all the chemistry done since Robert
Boyle as well as his own envisioning of
Parallelism; Rhetorical construction
e main objective of the sentence is to describe
“Essay on Heat and Light” as Davy’s presentation
of his own experiments and to further explain
that the essay served as both a critique of
previous chemistry and a vision of a new kind of
chemistry. e clearest, most e ective form for
providing this explanation of the essay’s function
is to make critique and vision both appositives of
“Essay on Heat and Light,” and to present them
in a parallel structure.
A Correct. e phrases describing the essay’s
function are presented in parallel form.
B Critique and his envisioning are not parallel;
the phrase and also his envisioning is
unnecessarily wordy; it is also unclear to
whom his refers.
C e two descriptors are not parallel.
D e two descriptors are not parallel.
E e meaning is confused in the assertion that
Davy critiqued his own vision of chemistry.
e correct answer is A.
743. To attract the most talented workers, some companies
are offering a wider range of bene ts, letting
employees pick those most important to them.
(A) bene ts, letting employees pick those most
important to them
(B) bene ts, letting employees pick the most
important of them to themselves
(C) bene ts and letting employees pick the most
important to themselves
(D) bene ts and let employees pick the most
important to them
(E) bene ts and let employees pick those that are
most important to themselves
Diction; Parallelism; Verb form
e sentence describes the bene t options o ered
by some companies, which allow employees
to pick those most important to them. Letting
maintains the progressive sense of are o ering;
those refers clearly and concisely to bene ts; and
them is the correct pronoun to serve as the object
of the preposition to.
A Correct. e sentence clearly and concisely
explains bene t options that allow
employees to pick those most important to
them.
B e most important of them to themselves
is wordy, and the function of themselves
is unclear. Normally, themselves would be
either re exive or emphatic, but in this
case it cannot reasonably be taken in either
of those ways. is nonstandard use of
the pronoun makes it unclear whether to
themselves is supposed to modify pick or most
important of them.
C e pronoun themselves is used incorrectly,
and its intended function is unclear.
Normally, themselves would be either
re exive or emphatic, but in this case it
cannot reasonably be taken in either of
those ways. is nonstandard use of the
pronoun makes it unclear whether to
themselves is supposed to modify pick or most
important of them.
D e present tense verb let incorrectly shifts
tense from the present progressive are
o ering.
9.8 Sentence Correction Answer Explanations
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GMAT® Offi cial Guide 2018
E e present tense verb let incorrectly
shifts tense from the present progressive
are o ering; the function of themselves is
unclear. Normally, themselves would be
either re exive or emphatic, but in this
case it cannot reasonably be taken in either
of those ways. is nonstandard use of
the pronoun makes it unclear whether to
themselves is supposed to modify pick or most
important of them.
e correct answer is A.
744. Many of the earliest known images of Hindu deities
in India date from the time of the Kushan Empire,
fashioned either from the spotted sandstone of
Mathura or Gandharan grey schist.
(A) Empire, fashioned either from the spotted
sandstone of Mathura or
(B) Empire, fashioned from either the spotted
sandstone of Mathura or from
(C) Empire, either fashioned from the spotted
sandstone of Mathura or
(D) Empire and either fashioned from the spotted
sandstone of Mathura or from
(E) Empire and were fashioned either from the
spotted sandstone of Mathura or from
Logical predication; Parallelism
e sentence makes two claims about the earliest
known images of Hindu deities in India: ey
date from the Kushan Empire, and they are
made from sandstone or schist. e clearest, most
e ective way to incorporate these two claims
into a single sentence is to provide two parallel
predicates for the single subject, the earliest known
images of Hindu deities in India. e two options
of media, presented as either/or choices, must
also be given in parallel structure: either from … or
from … or from either … or. …
A Placement of the modi er fashioned …
suggests that the Empire (the closest noun),
not the images of the deities, was fashioned
out of these materials; to parallel either
from , the preposition from should also
follow or .
B Parallelism requires that either precede the
rst appearance of from or that the second
appearance of from be eliminated.
C As in (A) and (B), the placement of the
modi er after Empire is misleading;
parallelism requires that the phrase fashioned
from , or another comparable verb and
preposition, follow or .
D Parallelism requires that a verb follow or ,
since a verb follows either .
E Correct. Two verbs, date and were fashioned ,
introduce parallel predicates for the subject,
earliest known images ; the choices of media
are correctly presented with the structure
either from … or from.
e correct answer is E.
745. Tides typically range from three to six feet, but while
some places show no tides at all, some others, such
as the Bay of Fundy, have tides of at least thirty feet
and more.
(A) some others, such as the Bay of Fundy, have
tides of at least thirty feet and more
(B) the others, such as the Bay of Fundy, that have
tides of more than thirty feet
(C) others, such as the Bay of Fundy, have tides of
more than thirty feet
(D) those at the Bay of Fundy, which has tides of
more than thirty feet
(E) the ones at the Bay of Fundy have tides of at
least thirty feet and more
Idiom; Grammatical construction
is sentence de nes typical tides and then draws
a contrast between locations with tides lower
than that norm and locations with tides higher
than the norm. e proper idiom for drawing this
contrast is some places and others—not some places
and some others as written. e height of tides
in places such as the Bay of Fundy is expressed
in a confusing manner since at least thirty feet
sets a lower limit on the height. is wording
is pointlessly redundant with the phrase and
more, which follows it. At least would normally
be used to indicate that the writer does not
know, or prefers not to say, whether the tides are
sometimes higher. And more rhetorically con icts
with this by signaling a de nite commitment
to the claim that they are (at least sometimes)
higher. A charitable reading suggests that tides of
more than thirty feet is the intended meaning.
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753
A e sentence contains repetitive and
redundant wording—some places and some
others, and at least thirty feet and more.
B e nal clause is incomplete because that
introduces a subordinate clause, leaving the
subject others with no main verb.
C Correct. A contrast is drawn between places
with low tides and places with high tides
using the expression some places and others,
and the height of the high tides is expressed
clearly and without redundancy.
D e pronoun those, which refers to places,
does not make sense along with at the Bay
of Fundy, which names a single place; the
nal clause is incomplete because which
introduces a subordinate clause, leaving the
subject those with no verb.
E e word ones, which refers to places, does
not make sense along with at the Bay of
Fundy, which names a single place; at
least thirty feet and more is redundant and
confusing.
e correct answer is C.
746. A leading gure in the Scottish Enlightenment, Adam
Smith’s two major books are to democratic capitalism
what Marx’s Das Kapital is to socialism.
(A) Adam Smith’s two major books are to
democratic capitalism what
(B) Adam Smith’s two major books are to
democratic capitalism like
(C) Adam Smith’s two major books are to
democratic capitalism just as
(D) Adam Smith wrote two major books that are to
democratic capitalism similar to
(E) Adam Smith wrote two major books that are to
democratic capitalism what
Idiom; Logical predication
A leading gure in the Scottish Enlightenment
describes Adam Smith, not his two books, so the
name of Adam Smith must immediately follow
the opening phrase. e comparison between
Smith’s books and Marx’s book is expressed as a
ratio, so the correct idiomatic expression is x is to
y what a is to b.
A e opening phrase is a dangling modi er
because it describes Smith, not his books.
B e opening phrase is a dangling modi er;
like is an incorrect word for making the
comparison.
C e opening phrase is a dangling modi er;
just as is an incorrect term for the
comparison.
D Similar to is an incorrect conclusion to the
comparison introduced by are to .
E Correct. e opening phrase is followed by
the subject that it modi es, Adam Smith,
and the comparison of the two men’s work
is presented idiomatically.
e correct answer is E.
747. Researchers studying the brain scans of volunteers
who pondered ethical dilemmas have found that the
basis for making tough moral judgments is emotion,
not logic or analytical reasoning.
(A) the brain scans of volunteers who pondered
ethical dilemmas have found that the basis for
making tough moral judgments is
(B) the brain scans of volunteers who pondered
ethical dilemmas and found the basis to make
tough moral decisions to be
(C) the brain scans of volunteers pondering ethical
dilemmas and found that the basis for making
tough moral decisions is
(D) volunteers’ brain scans while pondering ethical
dilemmas have found the basis to make tough
moral judgments to be
(E) volunteers’ brain scans while they pondered
ethical dilemmas have found that the basis for
making tough moral judgments is
Logical predication; Grammatical
construction
e sentence reports that researchers got volunteers
to ponder ethical dilemmas and make moral
judgments. Brain scans revealed that the volunteers’
judgments were based on emotion rather than
logical analysis. e main clause of this sentence
is Researchers . . . have found that . . .; embedded
within this sentence, the present participial phrase
studying . . . describes the researchers, the relative
clause who pondered . . . describes the volunteers,
and the object of the main verb appears as a noun
clause that the basis . . . is. . . .
9.8 Sentence Correction Answer Explanations
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GMAT® Offi cial Guide 2018
A Correct. e sentence is coherent and
grammatically correct.
B e use of the conjunction and immediately
before found indicates that the past tense
verbs pondered and found both have
volunteers as subject, but this changes the
original sentence, making it a long noun
phrase rather than a complete sentence.
C e conjunction and leaves the verb
found without a subject, and this changes
the original sentence into a sequence of
incoherently connected phrases rather than
a complete sentence.
D e phrase the basis to make is unidiomatic,
a su cient reason for rejecting this option.
e placement of the modi er while
pondering appears in a form parallel to
studying and means that the researchers,
not the volunteers, were pondering ethical
dilemmas. is does not make the sentence
incoherent, but creates a sentence that fails
to capture the meaning clearly intended in
the original sentence.
E Because the word volunteers’ is a possessive
form, and functions adjectivally as a
modi er of brain scans , they must refer back
to researchers rather than to volunteers’ . is
is not incorrect in itself, but, as with (D),
the resulting sentence fails to capture the
intended meaning of the original sentence.
e correct answer is A.
748. Rivaling the pyramids of Egypt or even the ancient
cities of the Maya as an achievement, the army of
terra‐cotta warriors created to protect Qin Shi Huang,
China’s rst emperor, in his afterlife is more than 2,000
years old and took 700,000 artisans more than 36
years to complete.
(A) the army of terra‐cotta warriors created to protect
Qin Shi Huang, China’s rst emperor, in his afterlife
is more than 2,000 years old and took 700,000
artisans more than 36 years to complete
(B) Qin Shi Huang, China’s rst emperor, was
protected in his afterlife by an army of terra-
cotta warriors that was created more than
2,000years ago by 700,000 artisans who took
more than 36 years to complete it
(C) it took 700,000 artisans more than 36 years to
create an army of terra‐cotta warriors more than
2,000 years ago that would protect Qin Shi Huang,
China’s rst emperor, in his afterlife
(D) more than 2,000 years ago, 700,000 artisans
worked more than 36 years to create an army
of terra‐cotta warriors to protect Qin Shi Huang,
China’s rst emperor, in his afterlife
(E) more than 36 years were needed to complete
the army of terra‐cotta warriors that 700,000
artisans created 2,000 years ago to protect
Qin Shi Huang, China’s rst emperor, in his
afterlife
Logical predication; Rhetorical
construction
e opening modi er, Rivaling the pyramids
… describes the army of terra‐cotta warriors ,
which must immediately follow the modi er.
e placement of the predicates that follow is
important; they must clarify two things about the
army of terra‐cotta warriors: how old it is and
how long it took to complete. e clearest and
most e ective way to express these two assertions
is as parallel verb phrases, is more than 2,000 years
old and took … more than 36 years to complete.
A Correct. e opening phrase correctly
modi es the subject, the army of terra‐cotta
warriors ; the placement of modi ers and
predicates in the main clause makes the
meaning of the sentence clear.
B Opening phrase is a dangling modi er
because it does not describe the subject
Qin Shi Huang ; in addition, the sentence is
awkward and unclear.
C Opening phrase is a dangling modi er
because it does not describe the subject it ;
the sequence of information presented is
confusing and unclear.
D Opening phrase is a dangling modi er
because it does not describe the subject
700,000 artisans .
E Opening phrase is a dangling modi er
because it does not describe the subject
more than 36 years .
e correct answer is A.
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755
749. In California, a lack of genetic variation in the Argentine
ant has allowed the species to spread widely; due to
their being so genetically similar to one another, the
ants consider all their fellows to be a close relative and
thus do not engage in the kind of erce intercolony
struggles that limits the spread of this species in its
native Argentina.
(A) due to their being so genetically similar to one
another, the ants consider all their fellows to be
a close relative and thus do not engage in the
kind of erce intercolony struggles that limits
(B) due to its being so genetically similar, the ant
considers all its fellows to be a close relative
and thus does not engage in the kind of erce
intercolony struggles that limit
(C) because it is so genetically similar, the ant
considers all its fellows to be close relatives
and thus does not engage in the kind of erce
intercolony struggles that limits
(D) because they are so genetically similar to one
another, the ants consider all their fellows to be
close relatives and thus do not engage in the
kind of erce intercolony struggles that limit
(E) because of being so genetically similar to one
another, the ants consider all their fellows to be
a close relative and thus do not engage in the
kind of erce intercolony struggles that limits
Diction; Agreement
Words that express comparisons, such as similar ,
require either a plural object, with an optional
expression of the entities being compared, or
a singular object, in which case this explicit
comparison is required. us its being so genetically
similar , without this explicit comparison, is
incorrect. Also, the two sides of the construction
consider . . . to be must agree in number ( fellows . . .
close relatives , not fellows . . . a close relative ).
A Consider all their fellows to be a close relative
shows incorrect agreement, with plural
fellows and singular a close relative .
B Its being so genetically similar is incorrect
because there is no explicit statement of what
the ant is similar to; also, the plural fellows
and singular a close relative do not agree.
C It is so genetically similar is incorrect because
there is no explicit statement of what the
ant is similar to.
D Correct . e clause with similar uses the
plural they and an explicit to one another , and
agreement is respected between ants and
fellows .
E e plural fellows and singular a close relative
do not agree.
e correct answer is D.
750. Next month, state wildlife of cials are scheduled to
take over the job of increasing the wolf population in
the federally designated recovery area, the number
of which will however ultimately be dictated by the
number of prey in the area.
(A) area, the number of which will however
(B) area; the size of the population, however, will
(C) area, however the number of wolves will
(D) area; the number of which will, however,
(E) area, when the size of the population will,
however,
Grammatical construction; Diction
e point of the sentence is that the ultimate
size of the wolf population will be determined
according to the number of prey in the area.
However, the phrase the number of which has
no referent since it cannot logically refer to the
noncount noun population or to the singular
wolf, which is used adjectivally here to modify
population. e idea can be expressed clearly by
making the size of the population the subject of a
new independent clause: the size of the population
will be dictated by the number of prey.
A e number of which cannot logically refer
to the noncount noun population or to the
singular wolf, which is used adjectivally here
to modify population.
B Correct. e idea is expressed clearly with an
independent clause: the size of the population
will be dictated by the number of prey.
C However is intended to serve as a
conjunctive adverb between the two
independent clauses, but the punctuation of
the sentence creates confusion by suggesting
that however is modifying are scheduled. A
semicolon after area and a comma after
however would make the intended function
of however clear.
9.8 Sentence Correction Answer Explanations
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GMAT® Offi cial Guide 2018
D e number of which cannot logically refer
to the noncount noun population; the
semicolon creates confusion since it is not
followed by an independent clause.
E When illogically suggests that the size of
the population will be determined at the
moment wildlife o cials take over the task.
is con icts with the ensuing claim that
the determination will ultimately depend on
a long-term condition (the number of prey in
the area).
e correct answer is B.
751. About 5 million acres in the United States have been
invaded by leafy spurge, a herbaceous plant from
Eurasia with milky sap that gives mouth sores to cattle,
displacing grasses and other cattle food and rendering
rangeland worthless.
(A) States have been invaded by leafy spurge, a
herbaceous plant from Eurasia with milky sap
that gives mouth sores to cattle, displacing
grasses and other cattle food and rendering
(B) States have been invaded by leafy spurge, a
herbaceous plant from Eurasia, with milky sap,
that gives mouth sores to cattle and displaces
grasses and other cattle food, rendering
(C) States have been invaded by leafy spurge, a
herbaceous plant from Eurasia having milky sap
that gives mouth sores to cattle and displacing
grasses and other cattle food, rendering
(D) States, having been invaded by leafy spurge,
a herbaceous plant from Eurasia with milky
sap that gives mouth sores to cattle, displaces
grasses and other cattle food, and renders
(E) States, having been invaded by leafy spurge, a
herbaceous plant from Eurasia that has milky
sap giving mouth sores to cattle and displacing
grasses and other cattle food, rendering
Logical predication; Grammatical
construction
e sentence explains that leafy spurge causes
mouth sores in cattle and also displaces other
plants eaten by cattle. However, the structure of
the sentence seems, illogically, to indicate that
displacing grasses modi es either the immediately
preceding phrase (that gives mouth sores to cattle)
or the main subject of the sentence (about 5
million acres in the United States). A clearer way
to express the e ects of the leafy spurge invasion
is with a compound predicate in the subordinate
clause: that gives mouth sores ... and displaces
grasses.
A Displacing grasses appears illogically to
modify either about 5 million acres in the
United States or that gives mouth sores to
cattle.
B Correct. e e ects of the leafy spurge
invasion are expressed clearly with a
compound predicate in the subordinate
clause: that gives mouth sores ... and
displaces grasses. e parenthetical commas
around with milky sap make it clear that the
entire phrase that gives ... and displaces
... rendering ... is intended to modify a
herbaceous plant from Eurasia. Although
the sap may well be the means by which
the plant gives mouth sores to cattle, the
sentence can be well formed and meaningful
without making a de nite commitment to
whether that is the case.
C Having and displacing should not be
expressed in parallel form since the rst is a
permanent characteristic of leafy spurge and
the second refers to an e ect of the plant’s
invasion.
D e subject of the sentence, 5 million acres is
not clearly paired with a verb. e structure
of the sentence suggests that 5 million acres
may be the intended subject of both displaces
and renders but it is illogical to say that
5million acres displaces grasses and renders
rangeland worthless.
E e subject of the sentence, 5 million acres is
not clearly paired with a verb. e structure
of the sentence suggests that 5 million acres
may be the intended subject of both displaces
and renders but it is illogical to say that
5million acres displaces grasses and renders
rangeland worthless.
e correct answer is B.
752. While it costs about the same to run nuclear plants as
other types of power plants, it is the xed costs that
stem from building nuclear plants that makes it more
expensive for them to generate electricity.
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757
(A) While it costs about the same to run nuclear
plants as other types of power plants, it is the
xed costs that stem from building nuclear
plants that makes it more expensive for them to
generate electricity.
(B) While the cost of running nuclear plants is about
the same as for other types of power plants,
the xed costs that stem from building nuclear
plants make the electricity they generate more
expensive.
(C) Even though it costs about the same to run
nuclear plants as for other types of power
plants, it is the xed costs that stem from
building nuclear plants that makes the electricity
they generate more expensive.
(D) It costs about the same to run nuclear plants
as for other types of power plants, whereas
the electricity they generate is more expensive,
stemming from the xed costs of building
nuclear plants.
(E) The cost of running nuclear plants is about the
same as other types of power plants, but the
electricity they generate is made more expensive
because of the xed costs stemming from
building nuclear plants.
Agreement; Logical predication
e emphatic construction it is X that does Y
(as in the phrase it is Jane who knows the answer )
should be used only when there is a compelling
reason to emphasize the doer of the action. In
this sentence, the emphatic construction is used
without good reason.
A is sentence uses the emphatic structure it
is … that without justi cation. e singular
verb makes violates the agreement within the
structure. e verb makes should agree with
the notional subject ( the xed costs ), not with
the pronoun it .
B Correct. is answer choice clearly and
succinctly compares the two types of costs.
C In addition to using the more cumbersome
emphatic structure, this version violates
the agreement within the structure. e
verb should agree with the notional subject
( the xed costs ), not with the pronoun it .
D e preposition for is redundant in
comparing the two objects of run . Since it is
not clear what stemming … refers to, this is a
dangling modi er.
E e passive construction electricity … is
made more expensive because of … is wordy
and cumbersome. e preposition for is
necessary in the comparison of the costs.
e correct answer is B.
753. The 32 species that make up the dolphin family are
closely related to whales and in fact include the animal
known as the killer whale, which can grow to be 30
feet long and is famous for its aggressive hunting
pods.
(A) include the animal known as the killer whale,
which can grow to be 30 feet long and is
(B) include the animal known as the killer whale,
growing as big as 30 feet long and
(C) include the animal known as the killer whale,
growing up to 30 feet long and being
(D) includes the animal known as the killer whale,
which can grow as big as 30 feet long and is
(E) includes the animal known as the killer whale,
which can grow to be 30 feet long and it is
Rhetorical construction; Agreement
e subject of the sentence is the 32 species that
make up the dolphin family , and the sentence
makes two claims about them: ey are closely
related, and they include the killer whale. e
relative pronoun which restates the object of the
second verb, reintroducing the animal known as
the killer whale as the subject of a relative clause
followed by two parallel verbs: can grow and is
famous.
A Correct. In this concise sentence, verbs
agree in number with their subjects and the
relative pronoun which indicates clearly that
the animal known as the killer whale is the
subject of the verbs in the dependent clause.
B Changing the verb to the participial growing
introduces ambiguity, because it could
refer back to the subject of the sentence
( 32 species ).
9.8 Sentence Correction Answer Explanations
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GMAT® Offi cial Guide 2018
C e participial growing might refer to
the 32 species ; the introduction of being is
unnecessarily wordy and adds nothing in
terms of meaning.
D as big as is an idiomatically incorrect
expression of the comparison; the plural
verb form include is needed to match the
plural subject the 32 species .
E It simply restates the subject of the previous
phrase, introducing more words but no
additional meaning; the singular verb form
includes should be the plural form include .
e correct answer is A.
754. The rst trenches that were cut into a 500‐acre site
at Tell Hamoukar, Syria, have yielded strong evidence
for centrally administered complex societies in
northern regions of the Middle East that were arising
simultaneously with but independently of the more
celebrated city‐states of southern Mesopotamia, in
what is now southern Iraq.
(A) that were cut into a 500‐acre site at Tell
Hamoukar, Syria, have yielded strong evidence
for centrally administered complex societies in
northern regions of the Middle East that were
arising simultaneously with but
(B) that were cut into a 500‐acre site at Tell
Hamoukar, Syria, yields strong evidence that
centrally administered complex societies in
northern regions of the Middle East were arising
simultaneously with but also
(C) having been cut into a 500‐acre site at Tell
Hamoukar, Syria, have yielded strong evidence
that centrally administered complex societies in
northern regions of the Middle East were arising
simultaneously but
(D) cut into a 500‐acre site at Tell Hamoukar, Syria,
yields strong evidence of centrally administered
complex societies in northern regions of the
Middle East arising simultaneously but also
(E) cut into a 500‐acre site at Tell Hamoukar, Syria,
have yielded strong evidence that centrally
administered complex societies in northern
regions of the Middle East arose simultaneously
with but
Rhetorical construction; Agreement;
Grammatical construction
is sentence, explaining interconnections among
a number of events, needs to be streamlined
as much as possible in order to become
understandable. To this end, unnecessary words
and structures should be eliminated. Prominent
among these are the relative clauses beginning
with that. Additionally, the subject of this
sentence is the plural trenches , which requires a
plural verb.
A at were cut … and that were arising …
are unnecessarily wordy and create an
unnecessarily complicated and confusing
sentence structure.
B In addition to the unnecessarily wordy
relative clauses, the singular verb yields does
not agree with the plural subject trenches .
C Having been cut … is unnecessarily wordy;
arising simultaneously must be followed by
the preposition with in order to make sense.
D e singular verb yields does not agree with
the plural subject trenches ; also adds no
meaning to the sentence.
E Correct. Unnecessary clauses and phrases
are avoided, and the subject and verb of the
main clause agree in number.
e correct answer is E.
755. Companies are relying more and more on networked
computers for such critical tasks as inventory
management, electronic funds transfer, and electronic
data interchange, in which standard business
transactions are handled via computer rather than on
paper.
(A) in which standard business transactions are
handled via computer rather than on paper
(B) where computers handle standard business
transactions rather than on paper
(C) in which computers handle standard business
transactions instead of on paper
(D) where standard business transactions are
handled, not with paper, but instead via
computer
(E) in which standard business transactions are
being handled via computer, in place of on paper
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759
Idiom; Logical predication; Rhetorical
construction
e concluding comparison in this sentence
uses the idiom rather than , which requires
parallel structures. In this sentence the
prepositional phrase via computer parallels on
paper . Substituting where for in which creates a
nonstandard idiom.
A Correct. is sentence uses standard
idiomatic constructions and avoids the
problems that are found in the other
versions.
B Where is a nonstandard way to refer to a
noun that does not name a location. If
electronic data interchange were a location,
this version would entail the odd claim that
on paper is an alternative location at which
computers would be expected to process
information.
C e comparison of the clause computers
handle . . . with the prepositional phrase on
paper illogically treats a location ( on paper )
as an alternative to an activity ( computers
handle ).
D As in (B), where is a nonstandard idiom.
e commas around not with paper appear
to make this phrase parenthetical; thus, it is
somewhat unclear what instead via computer
is contrasted with.
E e pile of prepositions in the phrase in
place of on paper is unnecessarily confusing
and wordy.
e correct answer is A.
756. Combining enormous physical strength with higher
intelligence, the Neanderthals appear as equipped for
facing any obstacle the environment could put in their
path, but their relatively sudden disappearance during
the Paleolithic era indicates that an inability to adapt to
some environmental change led to their extinction.
(A) appear as equipped for facing any obstacle the
environment could put in their path,
(B) appear to have been equipped to face any
obstacle the environment could put in their path,
(C) appear as equipped to face any obstacle the
environment could put in their paths,
(D) appeared as equipped to face any obstacle the
environment could put in their paths,
(E) appeared to have been equipped for facing any
obstacle the environment could put in their path,
Verb form; Diction
Because Neanderthals “disappeared,” the verb
describing their apparent abilities cannot be
present tense, so as equipped must be changed to to
have been equipped. e expression equipped to face
is clearer and more direct than equipped for facing.
A As equipped indicates that Neanderthals
still appear this way; equipped should be
followed by an in nitive form instead of a
prepositional phrase.
B Correct. e verb tense clearly indicates
that the current evidence is about
Neanderthals in the past.
C As equipped does not indicate that
Neanderthals appeared this way in the past;
while individual Neanderthals may well
have followed di erent paths, this sentence
is about the single evolutionary path taken
by Neanderthals as a species.
D Present‐tense appear is needed to parallel
present‐tense indicates and to reinforce that
this is current evidence about Neanderthals
in the past; as in (C), paths should be singular.
E For facing is an incorrect substitution of a
prepositional phrase for an in nitive.
e correct answer is B.
757. To map Earth’s interior, geologists use a network of
seismometers to chart seismic waves that originate
in the earth’s crust and ricochet around its interior,
most rapidly traveling through cold, dense regions and
slower through hotter rocks.
(A) interior, most rapidly traveling through cold,
dense regions and slower
(B) interior, which travel most rapidly through cold,
dense regions, and more slowly
(C) interior, traveling most rapidly through cold,
dense regions and more slowly
(D) interior and most rapidly travel through cold,
dense regions, and slower
(E) interior and that travel most rapidly through cold,
dense regions and slower
9.8 Sentence Correction Answer Explanations
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760
GMAT® Offi cial Guide 2018
Grammatical construction; Parallelism
is sentence explains in detail an activity of
geologists (using seismometers to chart waves),
focusing primarily on the object, seismic waves.
A description of these waves is developed
in a relative clause ( that originate . . . hotter
rocks ) that contains a compound verb phrase
( originate . . . ricochet . . . ). e action, ricochet ,
is further described in a participial phrase in
which traveling . . . is then further described in
a comparison of travel speeds in cold and hot
regions of Earth’s crust.
A e two expressions of comparison should
be parallel. Because most rapidly is placed
before the verb, it appears to modify the
entire ensuing phrase, including slower .
is and the contrast between the forms of
rapidly and slower make the comparisons
nonparallel. Some usage advisers consider
slower to be only an adjective. Although
slower is sometimes used as an adverb,
that usage would be more appropriate
with the parallel faster . e stark contrast
between this typically adjectival form and
the clearly adverbial ly form is somewhat
jarring.
B e referent of the relative pronoun which is
unclear.
C Correct. e modi ers are parallel and
correctly positioned in relation to the verb.
D is version of the sentence o ers travel as
a compound verb parallel with originate and
ricochet rather than as a description of how
the waves ricochet. It has the same problems
with parallelism as (A).
E Adding a relative clause and that . . . makes
this sentence wordy and awkward.
e correct answer is C.
758. Prices at the producer level are only 1.3 percent
higher now than a year ago and are going down,
even though oods in the Midwest and drought in the
South are hurting crops and therefore raised corn and
soybean prices.
(A) than a year ago and are going down, even
though oods in the Midwest and drought in the
South are hurting crops and therefore raised
(B) than those of a year ago and are going down,
even though oods in the Midwest and drought in
the South are hurting crops and therefore raising
(C) than a year ago and are going down, despite
oods in the Midwest and drought in the South,
and are hurting crops and therefore raising
(D) as those of a year ago and are going down, even
though oods in the Midwest and drought in the
South hurt crops and therefore raise
(E) as they were a year ago and are going down,
despite oods in the Midwest and drought in
the South, and are hurting crops and therefore
raising
Logical predication; Verb form
e sentence as written makes an illogical
comparison between prices at the producer level
and a time period ( a year ago ); surely the intended
comparison is between such prices now and
those of a year ago. e clause at the end of the
sentence states that ooding and a drought are
hurting crops, and as a result of this, they have
raised prices of certain crops. Are hurting is in
the present progressive tense, indicating an
ongoing process; raised is in the simple past tense,
indicating a completed action. It would be more
appropriate to use the present progressive tense
here as well, [are] raising .
A e rst part of this version of the sentence
illogically compares prices to a time; the
second part of the sentence indicates that
a completed action ( raised . . . prices ) results
from an ongoing present condition ( oods . . .
and drought . . . are hurting crop s).
B Correct. is version of the sentence makes
an appropriate comparison (between prices
now and those of a year ago), and uses
tenses in an appropriate way.
C Like (A), this version of the sentence illogically
compares prices to time past. Furthermore, in
this version, Prices is the subject not only for
the verb are but also for the verbs are hurting
and [are] raising , which makes no sense.
D e comparative adjective higher requires
the comparative term than instead of as ; the
tenses of the verbs in the latter half of the
sentence, hurt (simple past) and raise (simple
present), do not work together logically.
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761
E Like (D), this version inappropriately uses
as instead of than with higher . Furthermore,
like (C), in this version [ p ] rices is the subject
not only for the verb are but also for the
verbs are hurting and [are] raising .
e correct answer is B.
759. Fossils of the arm of a sloth found in Puerto Rico in
1991, and dated at 34 million years old, made it the
earliest known mammal of the Greater Antilles Islands.
(A) sloth found in Puerto Rico in 1991, and dated at
34 million years old, made it the earliest known
mammal of
(B) sloth, that they found in Puerto Rico in 1991, has
been dated at 34 million years old, thus making
it the earliest mammal known on
(C) sloth that was found in Puerto Rico in 1991, was
dated at 34 million years old, making this the
earliest known mammal of
(D) sloth, found in Puerto Rico in 1991, have been
dated at 34 million years old, making the sloth
the earliest known mammal on
(E) sloth which, found in Puerto Rico in 1991, was
dated at 34 million years old, made the sloth the
earliest known mammal of
Agreement; Logical predication
e subject of the sentence is the plural fossils , not
sloth , and therefore requires a plural verb. It therefore
does not have a singular antecedent. To clarify the
identi cation of the oldest known mammal, the
noun the sloth must be explicitly identi ed.
A Because sloth is the object of a preposition
and not the subject of the sentence, there is
no reasonable antecedent for the pronoun it ;
in this construction, the subject of made is
fossils , but it makes no sense to say that the
fossils made it the earliest known mammal.
B e introduction of the mysterious they, a
pronoun without a reference, adds confusion
to this sentence; the singular verb does not
agree with the plural subject.
C e relative clause that was … is wordy and
awkward; the singular verb does not agree
with the plural subject.
D Correct. e plural verb agrees with its
plural subject, and the sloth is explicitly
identi ed as the earliest known mammal.
E e singular verb does not agree with the
plural subject.
e correct answer is D.
760. Recently physicians have determined that stomach
ulcers are not caused by stress, alcohol, or rich foods,
but a bacterium that dwells in the mucous lining of the
stomach.
(A) not caused by stress, alcohol, or rich foods, but
(B) not caused by stress, alcohol, or rich foods, but
are by
(C) caused not by stress, alcohol, or rich foods, but
by
(D) caused not by stress, alcohol, and rich foods,
but
(E) caused not by stress, alcohol, and rich foods,
but are by
Parallelism; Diction
e formula used in this sentence not this but that
requires parallel elements following not and but.
is means that not by stress, alcohol, or rich foods
must be balanced by but by a bacterium. … ere
is no need to repeat the verb are caused , or even
the auxiliary verb are , because the verb precedes
the not by … but by … formula. e substitution
of the conjunction and for the conjunction or
changes the meaning of the sentence: Stress,
alcohol and rich foods identi es the combination
of these three factors as a suggested cause of
stomach ulcers, whereas stress, alcohol, or rich foods
o ers three individual possibilities. ere is no
way to tell which one of these is the intended
meaning of the sentence.
A To preserve parallelism, but should be
followed by by .
B ere is no reason to repeat the auxiliary
verb are .
C Correct. is sentence correctly uses the not
by … but by … formula.
D To preserve parallelism, but should be
followed by by .
E To preserve parallelism, but should be
followed by by .
e correct answer is C.
9.8 Sentence Correction Answer Explanations
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762
GMAT® Offi cial Guide 2018
761. The eyes of the elephant seal adapt to darkness
more quickly than any other animal yet tested,
thus allowing it to hunt ef ciently under the gloomy
conditions at its feeding depth of between 300 and
700 meters.
(A) The eyes of the elephant seal adapt to darkness
more quickly than any other animal yet tested,
thus allowing it
(B) The eyes of the elephant seal adapt to darkness
more quickly than does any other animal yet
tested, allowing them
(C) The eyes of the elephant seal adapt to darkness
more quickly than do those of any other animal
yet tested, allowing it
(D) Because they adapt to darkness more quickly
than any other animal yet tested, the eyes of the
elephant seal allow it
(E) Because the eyes of the elephant seal adapt
to darkness more quickly than do those of any
other animal yet tested, it allows them
Logical predication; Agreement
Logically, the eyes of the elephant seal should
be contrasted with the eyes of other animals, not
with the animals themselves. e sentence must
make this comparison directly and precisely,
with each subject interpretable as the subject of
adapt . Given the correct subject ( those of any other
animal yet tested ), which is plural, any reference to
it must also be plural.
A Any other animal yet tested is incorrectly set
up as the subject of adapt .
B Any other animal yet tested is incorrectly
set up as the subject of adapt . e plural
pronoun them seems to refer to eyes.
Although there is a sense in which eyes can
hunt, it is more reasonable to suppose that,
in this context, the writer’s intention is to
mention how the eyes’ quick adaptation
allows the seal to hunt e ciently.
C Correct. e subject of the comparative
phrase is correctly those of any other animal
yet tested , the plural verb do correctly
agrees with this subject ( those ), and the
singular pronoun it correctly agrees with its
antecedent ( elephant seal ) .
D Any other animal yet tested is incorrectly set
up as the subject of adapt .
E e subject is correct, but in the following
clause it has no clear referent.
e correct answer is C.
762. A mutual fund having billions of dollars in assets will
typically invest that money in hundreds of companies,
rarely holding more than one percent of the shares of
any particular corporation.
(A) companies, rarely holding more than one percent
(B) companies, and it is rare to hold at least one
percent or more
(C) companies and rarely do they hold more than
one percent
(D) companies, so that they rarely hold more than
one percent
(E) companies; rarely do they hold one percent or
more
Agreement; Logical predication
e participial phrase starting with rarely holding
is predicated of the main subject a mutual fund .
It elaborates on the e ect of the main clause
verb: since a mutual fund invests in hundreds of
companies, it rarely holds more than one percent
in any particular corporation.
A Correct. e participle holding in the
embedded clause correctly refers to a mutual
fund. It also correctly expresses the cause‐and‐
e ect relationship between investing in many
companies and holding little in each company.
B e antecedent of it is rare to hold is not
clear. e use of it is rare instead of rarely
could be misleading.
C e use of and between the clauses makes
them both main clauses. us, the cause‐
and‐e ect relationship between investing
and holding is lost. e referent of they is
unclear. It makes no sense to suppose that it
refers to the hundreds of companies. Since it
presumably refers to a mutual fund , it should
be singular.
D e pronoun they refers to a mutual fund
and thus should be singular.
E e pronoun they refers to a mutual fund
and thus should be singular.
e correct answer is A.
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763
763. Positing an enormous volcanic explosion at the end
of the Permian period would explain the presence of a
buried crater, account for the presence of the element
iridium (originating deep within the earth), and the
presence of quartz having been shattered by high-
impact shock waves.
(A) account for the presence of the element iridium
(originating deep within the earth), and the
presence of quartz having been
(B) of the element iridium (originating deep within the
earth), and of quartz
(C) the element iridium (originating deep within the
earth), and explain the presence of quartz having
been
(D) the presence of the element iridium (originating
deep within the earth), and explain the presence
of quartz
(E) explain the element iridium (originating deep
within the earth), and the presence of quartz
Parallelism; Rhetorical construction
e sentence indicates that a volcanic explosion
would explain the presence of three features,
but those features are not expressed using
parallel grammatical structures. e rst two
items in the list are verb phrases that involve
needless repetition—explain the presence of and
account for the presence of—while the third is an
awkwardly worded noun phrase—the presence of
quartz having been shattered. e three features
can be identi ed more concisely with a list
of prepositional phrases following explain the
presence: of a buried crater, of the element iridium,
and of quartz.
A e three features are not listed in parallel
form; the sentence is wordy and awkward.
B Correct. e three features are identi ed
with parallel prepositional phrases.
C e three features are not listed in parallel
form since the rst and third are verb
phrases, while the second is a noun phrase;
the wording is awkward and needlessly
repetitive.
D e three features are not listed in parallel
form since the rst and third are verb
phrases, while the second is a noun phrase;
the wording is needlessly repetitive.
E e three features are not listed in parallel
form since the rst and second are verb
phrases, while the third is a noun phrase; the
sentence illogically states that an explosion
would explain the element iridium, rather
than explain the presence of the element.
e correct answer is B.
764. The 19‐year‐old pianist and composer performed his
most recent work all over Europe, Asia, and North
America last year, winning prestigious awards in both
London as well as Tokyo for his achievement at so
young an age, and he is hoping to continue composing
now that he has returned to Chicago.
(A) winning prestigious awards in both London as
well as Tokyo for his achievement at so young an
age, and he is hoping
(B) winning prestigious awards both in London and
Tokyo for his achievement at such a young age,
and hoping
(C) having won prestigious awards both in London
and Tokyo for his achievement at so young an
age, hoping
(D) winning prestigious awards in both London and
Tokyo for his achievement at such a young age,
and he hopes
(E) having won prestigious awards both in London as
well as Tokyo for his achievement at so young an
age, and he hopes
Idiom; Grammatical construction
is sentence is about the past accomplishments
and the future ambitions of a musician who
recently won awards on a world tour. In some of
the versions of the sentence, the phrase as well as
is redundant with the word both before London
and Tokyo . Idiomatically, the simple conjunction
and completes the phrase beginning with both .
A e phrase as well as between London and
Tokyo is not idiomatic (the idiomatic formula
is both X and Y ). e present progressive verb
is hoping is unnecessarily wordy.
B Because hoping is parallel with winning ,
it suggests that the hoping and winning
are contemporaneous, whereas in fact the
musician won his awards last year but is
now, in the present, upon his return, hoping
to continue composing.
9.8 Sentence Correction Answer Explanations
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764
GMAT® Offi cial Guide 2018
C e present‐perfect participial phrase
having won suggests that his winning
took place before his performance tour.
Furthermore, the use of hoping in this
version of the sentence suggests that hoping
is something the pianist did while on his
performance tour last year , but the nal
phrase, now that he has returned to Chicago ,
indicates this is not so.
D Correct. is version of the sentence usesthe
correct idiomatic formula ( both X and Y ).
E e participial phrase having won . . .
inaccurately states that the musician won
his awards prior to his performance tour.
Furthermore, both in London as well as Tokyo
is unidiomatic, as indicated in the discussion
of (A) above, and unparallel ( in should
either precede both , or else in should be
added before Tokyo ).
e correct answer is D.
765. Star sh, with anywhere from ve to eight arms,
have a strong regenerative ability, and if one arm is
lost it quickly replaces it, sometimes by the animal
overcompensating and growing an extra one or two.
(A) one arm is lost it quickly replaces it, sometimes
by the animal overcompensating and
(B) one arm is lost it is quickly replaced, with the
animal sometimes overcompensating and
(C) they lose one arm they quickly replace it,
sometimes by the animal overcompensating,
(D) they lose one arm they are quickly replaced, with
the animal sometimes overcompensating,
(E) they lose one arm it is quickly replaced,
sometimes with the animal overcompensating,
Agreement; Idiom
In a conditional sentence if X, (then) Y , rhetorical
ow is enhanced by the two clauses sharing the
same structure. If one clause is passive, the other
should be passive; if one clause is active, the other
should be active, too.
A e conditional clause has a passive verb,
while the result clause has an active verb.
e pronoun it should be plural since it
refers to star sh . We know that star sh is
plural in this sentence because it agrees with
have in the main clause.
B Correct. e conditional structure is clear
and correct.
C is answer choice allows the unintended
reading that the animal replaces the missing
arm by overcompensating. e logical
connection between overcompensating and
growing is unclear.
D e conditional clause has an active verb,
while the result clause has a passive verb.
e second they should refer to arm , so
the agreement is not correct. e logical
connection between overcompensating and
growing is unclear.
E e conditional clause has an active
verb, while the result clause has a passive
verb. e logical connection between
overcompensating and growing is unclear.
e correct answer is B.
766. In 2000, a mere two dozen products accounted for
half the increase in spending on prescription drugs,
a phenomenon that is explained not just because of
more expensive drugs but by the fact that doctors
are writing many more prescriptions for higher‐cost
drugs.
(A) a phenomenon that is explained not just because
of more expensive drugs but by the fact that
doctors are writing
(B) a phenomenon that is explained not just by the
fact that drugs are becoming more expensive
but also by the fact that doctors are writing
(C) a phenomenon occurring not just because of
drugs that are becoming more expensive but
because of doctors having also written
(D) which occurred not just because drugs are
becoming more expensive but doctors are also
writing
(E) which occurred not just because of more
expensive drugs but because doctors have also
written
Rhetorical construction; Idiom
is sentence explains that a few high‐cost
products account for increased spending for
two reasons—rising drug prices and more
prescriptions for high‐priced drugs. To present
these two causes, the sentence employs a formula
that requires parallel elements: not just because
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765
of x, but because of y , with x and y assuming the
same grammatical form. One way to create this
parallelism is to phrase both contributing causes
as noun clauses beginning with the fact that .
To streamline the sentence, unnecessary words
and redundancies should be eliminated. One
such redundancy is the repetition of meaning in
explained and because of.
A It is redundant and confusing to say that
the phenomenon in question is explained …
because of ; the sentence structure is not parallel.
B Correct. is sentence correctly uses
parallel structure.
C e phrasing drugs that are becoming and
doctors having also written are awkward and
confusing; the placement of also is incorrect.
D e structure of this sentence is not parallel.
E e placement of also is incorrect; the
structure of the sentence is not parallel.
e correct answer is B.
767. Similar to other early Mississippi Delta blues singers, the
music of Robert Johnson arose from an oral tradition
beginning with a mixture of chants, ddle tunes, and
religious music and only gradually evolved into the blues.
(A) Similar to other early Mississippi Delta blues
singers, the music of Robert Johnson arose from
an oral tradition beginning with
(B) Similar to that of other early Mississippi Delta
blues singers, Robert Johnson made music that
arose from an oral tradition that began with
(C) As with other early Mississippi Delta blues
singers, Robert Johnson made music that arose
from an oral tradition beginning as
(D) Like other early Mississippi Delta blues singers,
Robert Johnson’s music arose from an oral
tradition beginning with
(E) Like the music of other early Mississippi Delta
blues singers, the music of Robert Johnson
arose from an oral tradition that began as
Logical predication; Verb form
e sentence aims to compare the music of
early Mississippi Delta Blues singers with the
music of Robert Johnson. But what it does is
illogically compare singers themselves with the
music of Johnson. e second half of the sentence
describes two stages of the oral tradition from
which blues developed.
A Similar to is a wordy and imprecise form
of comparison here. e second half of the
sentence attempts to describe the stages of
the oral tradition, but in a nonparallel form,
presenting the rst stage as a participial
phrase and the second as a verb phrase.
B Similar to is wordy and imprecise. e
pronoun that lacks a grammatical referent.
C e comparative phrase as with is an
inappropriate form for comparing nouns
and noun phrases. e second half of the
sentence violates parallelism, attempting to
express the rst stage of the oral tradition as
a present‐participle phrase and the second
as a past‐tense verb phrase.
D is makes a sentence that illogically
compares singers with music . It violates
parallelism by coupling a participial phrase
beginning with . . . with a verb phrase
evolved into. . . .
E Correct. e resulting sentence compares
like with like. It uses a relative clause to
describe the oral tradition from which blues
developed, indicating the two stages of
development with two verbs in parallel.
e correct answer is E.
768. Thelonious Monk, who was a jazz pianist and
composer, produced a body of work both rooted in
the stride‐piano tradition of Willie (The Lion) Smith and
Duke Ellington, yet in many ways he stood apart from
the mainstream jazz repertory.
(A) Thelonious Monk, who was a jazz pianist and
composer, produced a body of work both rooted
(B) Thelonious Monk, the jazz pianist and composer,
produced a body of work that was rooted both
(C) Jazz pianist and composer Thelonious Monk,
who produced a body of work rooted
(D) Jazz pianist and composer Thelonious Monk
produced a body of work that was rooted
(E) Jazz pianist and composer Thelonious Monk
produced a body of work rooted both
9.8 Sentence Correction Answer Explanations
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766
GMAT® Offi cial Guide 2018
Grammatical construction; Rhetorical
construction
e subject of the sentence is elonious Monk ,
and the sentence tells about two things that
he did: produced and stood apart. e work
he produced was rooted in the mainstream
( stride piano ) jazz tradition, yet at the same
time, he deviated from this tradition. e use
of a relative clause ( who was a jazz pianist …)
or an appositive ( the jazz pianist …) introduces
unnecessary wordiness and grammatical
complexity. Since only one point is being made
about Monk’s body of work, the appearance
of the word both in the clause presenting the
claim about Monk’s work is deceptive as well as
grammatically incorrect.
A e relative clause introduces wordiness and
confusion.
B e appositive introduces wordiness and
unnecessary grammatical complexity.
C e sentence is a fragment because the main
subject, elonious Monk , has no verb.
D Correct. e sentence concisely identi es
elonious Monk and expresses the single
point about his work without unnecessary
or misleading words.
E e appearance of both is misleading, since
only one point is being made about where
Monk’s musical roots are located.
e correct answer is D.
769. Nobody knows exactly how many languages there
are in the world, partly because of the dif culty
of distinguishing between a language and the
sublanguages or dialects within it, but those who have
tried to count typically have found about ve thousand.
(A) and the sublanguages or dialects within it, but
those who have tried to count typically have found
(B) and the sublanguages or dialects within them, with
those who have tried counting typically nding
(C) and the sublanguages or dialects within it, but
those who have tried counting it typically nd
(D) or the sublanguages or dialects within them, but
those who tried to count them typically found
(E) or the sublanguages or dialects within them,
with those who have tried to count typically
nding
Agreement; Idiom
is sentence rst introduces a condition that makes
it di cult to count languages and then, with the
conjunction but , introduces the topic of those who
defy these di culties and try to count the world’s
languages anyway. Connecting these two parts of the
sentence with but indicates that the second clause of
the sentence is counter to expectation. e challenges
of the task are explained using the example of
a single language and its many sublanguages or
dialects. When this example is referred to with a
pronoun, the pronoun should be singular; when
the languages being counted are referred to with a
pronoun, this pronoun must be plural.
A Correct. e pronoun it agrees in number
to its singular antecedent, and but indicates
that the idea expressed in the nal clause
de es expectations.
B e plural pronoun them incorrectly refers to
the singular antecedent language ; connecting
the two clauses with the preposition with
loses the sense that counting languages
despite the di culties de es expectations.
C e second appearance of it , referring to
world languages, is incorrect because it does
not agree in number with languages .
D e conjunction or is incorrect—the
idiomatic expression is distinguishing between
x and y ; the plural pronoun them does not
agree with the singular antecedent language .
E e plural pronoun them incorrectly refers
to the singular antecedent, language; with is
an imprecise connector for the two clauses,
losing the counter‐to‐expectation relationship
between them.
e correct answer is A.
770. Although a number of excellent studies narrate
the development of domestic technology and
its impact on housewifery, these works do not
discuss the contributions of the women employed
by manufacturers and utility companies as product
demonstrators and publicists, who initially promoted
new and unfamiliar technology to female consumers.
(A) by manufacturers and utility companies as
product demonstrators and publicists,
(B) to be product demonstrators and publicists by
manufacturers and utility companies,
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767
(C) to demonstrate and publicize their products by
manufacturers and utility companies
(D) by manufacturers and utility companies to be
demonstrators and publicists of their products
(E) by manufacturers and utility companies to
demonstrate and publicize their products
Logical predication; Rhetorical
construction
e point of the sentence is that studies do
not include the contributions of women who
promoted new domestic technology. e sentence
indicates clearly that the women were employed
by manufacturers and utility companies, worked as
product demonstrators and publicists, and promoted
new technology to female consumers.
A Correct. e sentence clearly describes the
women’s employment and contributions.
B is sentence structure appears to make who
initially promoted refer to manufacturers and
utility companies rather than to the women.
is con icts with the use of the word who,
which would normally be expected to refer
to persons rather than to abstract entities
such as companies.
C eir refers to the women, incorrectly
suggesting that the products belong to them.
is sentence structure appears to make who
initially promoted refer to manufacturers and
utility companies rather than to the women. is
con icts with the word who, which would
normally be expected to refer to persons rather
than to abstract entities such as companies.
D Who initially promoted follows, and appears
to refer to, products, which cannot logically
be the referent.
E Who initially promoted follows, and appears
to refer to, products, which cannot logically
be the referent.
e correct answer is A.
771. The absence from business and nancial records of
the nineteenth century of statistics about women leave
us with no record of the jobs that were performed by
women and how they survived economically.
(A) from business and nancial records of the
nineteenth century of statistics about women
leave us with no record of the jobs that were
performed by women and
(B) from business and nancial records of statistics
about women from the nineteenth century leave
us with no record of what jobs women performed
or
(C) of statistics for women from business and
nancial records in the nineteenth century leaves
us with no record of either the jobs that women
were performing and of
(D) of statistics on women from business and
nancial records in the nineteenth century
leave us with no record of the jobs that women
performed or of
(E) of statistics about women from business and
nancial records of the nineteenth century leaves
us with no record of either what jobs women
performed or
Rhetorical construction; Agreement
is sentence is phrased awkwardly in two ways.
e rst relates to absence of statistics : it is best
to place a noun modi er right next to the noun
that it modi es, with no intervening material.
Second, jobs that were performed by women is
more complicated than necessary— jobs women
performed is better, for example. Also, the singular
noun absence requires the correct agreeing verb
form leaves .
A Absence and of statistics are widely separated,
and leave does not properly agree with its
subject, absence.
B Absence and of statistics are widely separated,
and leave does not properly agree with its
subject, absence.
C Jobs that women were performing is
unnecessarily long and complex. e either
construction should be completed with or ,
not and .
D Leave does not properly agree with its
subject, absence.
E Correct. Leaves agrees with absence. e
phrase of statistics is next to the noun it
modi es ( absence ), and jobs women performed
is a nicely simple phrasing.
e correct answer is E.
9.8 Sentence Correction Answer Explanations
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768
GMAT® Offi cial Guide 2018
772. Heating‐oil prices are expected to be higher this year
than last because re ners are paying about $5 a barrel
more for crude oil than they were last year.
(A) Heating‐oil prices are expected to be higher this
year than last because re ners are paying about
$5 a barrel more for crude oil than they were
(B) Heating‐oil prices are expected to rise higher this
year over last because re ners pay about $5 a
barrel for crude oil more than they did
(C) Expectations are for heating‐oil prices to be
higher this year than last year’s because re ners
are paying about $5 a barrel for crude oil more
than they did
(D) It is the expectation that heating‐oil prices will be
higher for this year over last because re ners
are paying about $5 a barrel more for crude oil
now than what they were
(E) It is expected that heating‐oil prices will rise
higher this year than last year’s because re ners
pay about $5 a barrel for crude oil more than
they did
Rhetorical construction; Idiom
e sentence connects a comparison between
this year’s and last year’s heating‐oil prices with
a comparison between this year’s and last year’s
crude‐oil prices. e most e cient, parallel
expression of those comparisons is to use two
comparative expressions, higher than and more
than.
A Correct. is sentence expresses the
comparison in succinct, parallel phrases.
B e comparative form, higher , anticipates
the comparative term than , not over ; in the
second clause, the comparative terms more
than should immediately follow $5 a barrel .
C Expectations are for … is an unnecessarily
wordy and indirect expression; the
possessive year’s is not parallel with the
adverbial phrase this year .
D It is the expectation that … is wordy and
awkward; for and what are unnecessary.
E It is expected that … is wordy and awkward;
the possessive last year’s does not parallel the
adverbial phrase this year .
e correct answer is A.
773. Even though Clovis points, spear points with
longitudinal grooves chipped onto their faces, have
been found all over North America, they are named for
the New Mexico site where they were rst discovered
in 1932.
(A) Even though Clovis points, spear points with
longitudinal grooves chipped onto their faces,
have been found all over North America, they are
named for the New Mexico site where they were
rst discovered in 1932.
(B) Although named for the New Mexico site where
rst discovered in 1932, Clovis points are spear
points of longitudinal grooves chipped onto
their faces and have been found all over North
America.
(C) Named for the New Mexico site where they have
been rst discovered in 1932, Clovis points, spear
points of longitudinal grooves chipped onto the
faces, have been found all over North America.
(D) Spear points with longitudinal grooves that are
chipped onto the faces, Clovis points, even
though named for the New Mexico site where
rst discovered in 1932, but were found all over
North America.
(E) While Clovis points are spear points whose faces
have longitudinal grooves chipped into them,
they have been found all over North America,
and named for the New Mexico site where they
have been rst discovered in 1932.
Verb form; Rhetorical construction; Logical
predication
Even though , although , and while introduce
clauses that appear to be logically incompatible
but in fact are not. In this sentence, the apparent
incompatibility that must be clearly expressed is
that although the spear points are named for a
particular place in New Mexico, they are in fact
found throughout North America. Because their
discovery took place in 1932 and is not ongoing,
the correct verb tense is simple past, not present
perfect.
A Correct. e even though clause expresses
clearly that the seeming incompatibility is
between where the spear points have been
found ( all over North America ) and the
naming of the spear points for a single site
in New Mexico.
![](asset-308.png)
769
B e sentence structure indicates that the
expected incompatibility is between the
geographically based name of the points and
their physical properties, which makes no
sense; where discovered is missing a subject—
the correct form is where they were rst
discovered .
C Have been rst discovered is the wrong
tense, since the discovery is a discrete event
completed in the past.
D e sequence of information in this
sentence is confusing; even though and but
both introduce information that is contrary
to expectation, so to use them both to
describe a single apparent contradiction is
redundant and nonsensical.
E While introduces a description of Clovis
points and suggests that this appears
incompatible with their appearance all over
North America, which makes no sense; have
been rst discovered is the wrong tense.
e correct answer is A.
774. Heavy commitment by an executive to a course of
action, especially if it has worked well in the past,
makes it likely to miss signs of incipient trouble or
misinterpret them when they do appear.
(A) Heavy commitment by an executive to a course
of action, especially if it has worked well in the
past, makes it likely to miss signs of incipient
trouble or misinterpret them when they do appear.
(B) An executive who is heavily committed to a course
of action, especially one that worked well in the
past, makes missing signs of incipient trouble or
misinterpreting ones likely when they do appear.
(C) An executive who is heavily committed to a
course of action is likely to miss or misinterpret
signs of incipient trouble when they do appear,
especially if it has worked well in the past.
(D) Executives’ being heavily committed to a course of
action, especially if it has worked well in the past,
makes them likely to miss signs of incipient trouble
or misinterpreting them when they do appear.
(E) Being heavily committed to a course of action,
especially one that has worked well in the past,
is likely to make an executive miss signs of
incipient trouble or misinterpret them when they
do appear.
Rhetorical construction; Logical predication
is sentence explains that an executive who is
blindly committed to a proven course of action is
likely to overlook or misinterpret indicators that
the plan may no longer be working. e sentence
needs to make clear who may misinterpret these
indicators.
A e passive construction causes the sentence
to be wordy and confusing; the reference
for it is ambiguous, leaving the reader with
questions about who or what is likely to
miss these signs.
B e sentence structure indicates that the
executive , not his or her strategy, causes signs
to be overlooked; the modi er when they do
appear is misplaced.
C e reference for the pronoun it is unclear
because many nouns have intervened
between the appearance of the logical
referent ( course of action ) and it .
D Misinterpreting should be an in nitive verb
form to parallel miss ; the phrasing throughout
the sentence is wordy and awkward.
E Correct. e grammatical structure of this
sentence and the appropriate placement of
modi ers expresses the meaning clearly and
concisely.
e correct answer is E.
775. According to recent studies comparing the nutritional
value of meat from wild animals and meat from
domesticated animals, wild animals have less total fat
than do livestock fed on grain and more of a kind of fat
they think is good for cardiac health.
(A) wild animals have less total fat than do livestock
fed on grain and more of a kind of fat they think is
(B) wild animals have less total fat than livestock fed
on grain and more of a kind of fat thought tobe
(C) wild animals have less total fat than that of
livestock fed on grain and have more fat of a
kind thought to be
(D) total fat of wild animals is less than livestock
fed on grain and they have more fat of a kind
thought to be
(E) total fat is less in wild animals than that of
livestock fed on grain and more of their fat is of
a kind they think is
9.8 Sentence Correction Answer Explanations
![](asset-309.png)
770
GMAT® Offi cial Guide 2018
Logical predication; Rhetorical construction
e sentence reports research ndings on the
comparison between the fat content of wild
animals and that of domestic livestock. e most
signi cant error in the sentence is in the phrase
they think : the pronoun they either lacks a referent
or is meant to refer back to wild animals , which
would be nonsensical.
A e pronoun they fails to refer correctly.
B Correct. e phrase thought to be eliminates
the most signi cant error in the original
sentence. Note that while the phrase less
total fat than livestock di ers from the phrase
less total fat than do livestock in the original,
either would be correct here.
C e resulting sentence is unnecessarily
wordy and confusing. e pronoun that is
not only super uous, but it fails to refer
back to anything.
D e resulting sentence makes a nonsensical
comparison between total fat and livestock .
E e resulting sentence is wordy and
confusing. It lacks the required parallelism
in wild animals . . . in livestock . e
referent of the possessive pronoun their is
ambiguous, as is the referent of the pronoun
they .
e correct answer is B.
776. Yellow jackets number among the 900 or so species
of the world’s social wasps, wasps living in a highly
cooperative and organized society where they consist
almost entirely of females—the queen and her sterile
female workers.
(A) wasps living in a highly cooperative and
organized society where they consist almost
entirely of
(B) wasps that live in a highly cooperative and
organized society consisting almost entirely of
(C) which means they live in a highly cooperative and
organized society, almost all
(D) which means that their society is highly
cooperative, organized, and it is almost entirely
(E) living in a society that is highly cooperative,
organized, and it consists of almost all
Idiom; Logical predication; Rhetorical
construction
is sentence identi es yellow jackets as one of 900
types of social wasps and provides an explanation
of the term social wasps. In this explanation, the
society or population—not the individual wasps
themselves—consists almost entirely of females.
e three descriptors of social wasps ( cooperative,
organized, and consisting almost entirely of females ) are
most e ectively expressed in parallel structures.
A ey , referring to wasps, is an incorrect
subject for consist .
B Correct. e three descriptors of the wasp
society are in parallel form, and consisting
properly modi es society .
C e sentence structure makes it unclear
what almost all females describes.
D And it is … violates the parallelism of the
three descriptors of social wasps.
E And it consists … violates the parallelism of
the three descriptors.
e correct answer is B.
777. Before 1988, insurance companies in California were
free to charge whatever rates the market would bear,
needing no approval from regulators before raising
rates.
(A) needing no approval from regulators before raising
(B) and it needed no approval by regulators before
raising
(C) and needing no approval from regulators before
they raised
(D) with approval not needed by regulators before
they raised
(E) with no approval needed from regulators before
the raising of
Logical predication; Rhetorical construction
e sentence explains that, prior to 1988,
insurance companies in California could raise
rates without regulators’ approval. is idea is
expressed concisely using a participial phrase and
two prepositional phrases: needing no approval
from regulators before raising rates. Unlike some of
the answer choices that contain errors involving
antecedents, this construction uses no pronouns
and contains no such errors.
![](asset-30a.png)
771
A Correct. e combination of a participial
phrase and two prepositional phrases
expresses the idea clearly with no errors
involving pronouns or antecedents.
B e singular pronoun it has no clear
antecedent. If it is taken to refer to the
market (the only grammatically plausible
antecedent), the sentence is illogical.
Whatever rates the market would bear clearly
indicates that market is being used in the
sense of an abstract set of forces a ecting
prices. To say that the market, in that sense,
raised taxes and that it needed no approval
to do so is nonsensical.
C e construction were … and needing
is ungrammatical. e pronoun they is
intended to refer to companies but could also
seem, illogically, to refer to regulators.
D By regulators illogically indicates that
regulators are the ones who did not need
approval; the pronoun they is intended
to refer to companies but could also seem,
illogically, to refer to regulators.
E Before the raising of is wordy and awkward.
Both that phrase and with no approval
needed are strangely uninformative and
rhetorically ine ective in that they appear
to pointedly avoid telling who did not need
the approval or who might have raised the
rates.
e correct answer is A.
778. Marconi’s conception of the radio was as a substitute
for the telephone, a tool for private conversation;
instead, it is precisely the opposite, a tool for
communicating with a large, public audience.
(A) Marconi’s conception of the radio was as a
substitute for the telephone, a tool for private
conversation; instead, it is
(B) Marconi conceived of the radio as a substitute
for the telephone, a tool for private conversation,
but which is
(C) Marconi conceived of the radio as a tool for
private conversation that could substitute for the
telephone; instead, it has become
(D) Marconi conceived of the radio to be a tool
for private conversation, a substitute for the
telephone, which has become
(E) Marconi conceived of the radio to be a substitute
for the telephone, a tool for private conversation,
other than what it is,
Rhetorical construction; Logical
predication
e main point of this sentence is to explain
that while Marconi felt the radio would
substitute for the phone as an instrument of
private communication, in fact it has become
an instrument of mass communication. It is
less wordy to use Marconi as the subject of the
active verb conceived than to use the subject
conception with the static verb was. e pronoun
it positioned as the subject of the nal verb
has become refers back to radio. Versions of the
sentence that use the relative pronoun which
indicate that the telephone has become a mass
medium.
A e nominalized subject, conception , leads to
a wordy and awkward sentence.
B e reference for the relative pronoun which
is ambiguous; the sentence as a whole is
awkward.
C Correct. An active verb makes the rst
clause more concise; it in the second clause
clearly refers to the radio .
D Conceived of … should be followed by as
rather than to be .
E Conceived of … should be followed by as
rather than to be ; other than what it is is
awkward, wordy, and redundant, overlapping
the meaning of precisely the opposite … .
e correct answer is C.
779. Because there are provisions of the new maritime code
that provide that even tiny islets can be the basis for
claims to the sheries and oil elds of large sea areas,
they have already stimulated international disputes
over uninhabited islands.
(A) Because there are provisions of the new maritime
code that provide that even tiny islets can be the
basis for claims to the sheries and oil elds of
large sea areas, they have already stimulated
(B) Because the new maritime code provides that
even tiny islets can be the basis for claims to the
sheries and oil elds of large sea areas, it has
already stimulated
9.8 Sentence Correction Answer Explanations
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772
GMAT® Offi cial Guide 2018
(C) Even tiny islets can be the basis for claims to the
sheries and oil elds of large sea areas under
provisions of the new maritime code, already
stimulating
(D) Because even tiny islets can be the basis for
claims to the sheries and oil elds of large
sea areas under provisions of the new maritime
code, this has already stimulated
(E) Because even tiny islets can be the basis for
claims to the sheries and oil elds of large
sea areas under provisions of the new maritime
code, which is already stimulating
Logical predication; Grammatical
construction
In this sentence, the there are … that …
construction contributes nothing more than
unnecessary words. e sentence needs to make
clear whether provisions or code is the subject of
the main verb stimulated .
A e there are … that … construction is
unnecessarily wordy; in the predicate
nominative instead of the subject position,
provisions is not an obvious referent for the
pronoun they .
B Correct. In this sentence, the new maritime
code is clearly the antecedent of it in the
main clause and thus the subject of has
already stimulated .
C Under provisions of the new maritime code is a
misplaced modi er, seeming to describe sea
areas ; the sentence does not make clear what
is stimulating … disputes .
D e referent of this is unclear.
E e sentence is a fragment, opening with
a dependent clause ( Because … code ) and
concluding with a relative clause, but
lacking a main, independent clause.
e correct answer is B.
780. Unlike the automobile company, whose research was
based on crashes involving sport utility vehicles, the
research conducted by the insurance company took
into account such factors as a driver’s age, sex, and
previous driving record.
(A) company, whose research was based on
(B) company, which researched
(C) company, in its research of
(D) company’s research, having been based on
(E) company’s research on
Logical predication; Rhetorical
construction
e point of the sentence is to contrast the
research conducted by the automobile company
and that conducted by the insurance company,
but the sentence has been written in a way that
contrasts the automobile company with research. e
correct contrast is between automobile company’s
research and research conducted by the insurance
company.
A Automobile company is incorrectly contrasted
with research.
B Automobile company is incorrectly contrasted
with research.
C Automobile company is incorrectly contrasted
with research.
D Having been based on is wordy. is
construction makes it unclear whether
having been based on crashes involving
sport utility vehicles is intended to modify
the automobile company’s research or the
research conducted by the insurance company.
e sentence structure slightly favors the
latter interpretation, but it is somewhat
implausible to suppose that this is the
intended meaning.
E Correct. e sentence concisely contrasts
the automobile company’s research and research
conducted by the insurance company.
e correct answer is E.
781. Gusty westerly winds will continue to usher in a
seasonably cool air mass into the region, as a broad
area of high pressure will build and bring fair and dry
weather for several days.
(A) to usher in a seasonably cool air mass into the
region, as a broad area of high pressure will
build and
(B) ushering in a seasonably cool air mass into the
region and a broad area of high pressure will
build that
(C) to usher in a seasonably cool air mass to the
region, a broad area of high pressure building, and
![](asset-30c.png)
773
(D) ushering a seasonably cool air mass in the
region, with a broad area of high pressure
building and
(E) to usher a seasonably cool air mass into the
region while a broad area of high pressure
builds, which will
Verb form; Grammatical construction;
Diction
e sentence o ers a prediction that two
concurrent weather events will bring a certain
type of weather, but its use of the phrase as
... will build causes confusion. e wording
makes the sequence of events and the causal
relationships among them unclear. Future tense
is used to indicate that winds will continue. e
relation of as to the rest of the sentence makes
it unclear whether as is intended as a logical
indicator (similar to because) or as a temporal
indicator (equivalent to while). If as is intended in
the former way, it would be preferable to resolve
the ambiguity by using a word or phrase such
as because or given that. If it is intended in the
latter way, a present tense verb would be needed
following as or while to show that the second
event is concurrent with, or part of, the future
situation: while high pressure builds. In addition,
usher in ... into is redundant and unidiomatic.
A clear, concise way to express this idea is will
continue to usher a seasonably cool air mass into the
region while a broad area of high pressure builds.
A Usher in … into is redundant and
unidiomatic. As … will build causes
confusion.
B e absence of a comma after region makes
this ungrammatical. Ushering in ... into
is redundant; will build is the wrong verb
tense; the plural verb bring does not agree
with area, the singular antecedent of that.
C e grammatical function of a broad area of
high pressure building is unclear.
D Ushering … in the region is incorrect since
into is needed to indicate movement from
outside in; the subject of the verb bring is
unclear.
E Correct. e idea is expressed with clear,
correct combinations of verbs and subjects.
e correct answer is E.
782. With the patience of its customers and with its network
strained to the breaking point, the on-line service
company announced a series of new initiatives trying
to relieve the congestion that has led to at least four
class-action lawsuits and thousands of complaints from
frustrated customers.
(A) the patience of its customers and with its
network strained to the breaking point, the on-
line service company announced a series of new
initiatives trying to relieve
(B) the patience of its customers and its network
strained to the breaking point, the on-line service
company announced a series of new initiatives
that try to relieve
(C) its network and the patience of its customers
strained to the breaking point, the on-line service
company announced a series of new initiatives to
try to relieve
(D) its network and with the patience of its
customers strained to the breaking point, the
on-line service company announced a series of
initiatives to try relieving
(E) its network and its customers’ patience strained
to the breaking point, the on-line service
company announced a series of new initiatives to
try relieving
Logical predication; Rhetorical
construction
e sentence explains the online service
provider’s e orts to relieve congestion, but it
has been written with confusing ambiguities.
Because the patience of its customers is in a separate
prepositional phrase from its network, it is not
clear whether both or only the latter is strained
to the breaking point. e phrase trying to relieve
is probably meant to explain the purpose of the
initiatives, but does not do so unambiguously
(for example, trying could modify either the
company or initiatives, and it is not clear which
is intended). An unambiguous wording of the
sentence would clarify that both the patience
of its customers and its network are strained to
the breaking point and that the purpose of the
initiatives is to try to relieve the congestion.
A e patience of its customers is not clearly linked
to strained to the breaking point; trying to relieve
is an ambiguous and unidiomatic way of
expressing the purpose of the initiatives.
9.8 Sentence Correction Answer Explanations
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774
GMAT® Offi cial Guide 2018
B at try to relieve fails to express the purpose
of the initiatives in a rhetorically acceptable
way; moreover the present tense try is
illogical here. e phrase the patience of
its customers and its network is rhetorically
awed in that its structure makes it seem to
be attributing patience to the network.
C Correct. e sentence indicates clearly
that both the patience of its customers and
its network are strained to the breaking point
and that the company introduced initiatives
aimed at relieving the congestion.
D Its network is not clearly linked to strained
to the breaking point; with to try, the
in nitive form to relieve is more rhetorically
appropriate here than the verbal noun form
relieving, in order to indicate the goal of the
intervention.
E With to try, the in nitive form to relieve
is more rhetorically appropriate here than
the verbal noun form relieving, in order to
indicate the goal of the intervention.
e correct answer is C.
783. November is traditionally the strongest month for sales
of light trucks, but sales this past November, even
when compared with sales in previous Novembers,
accounted for a remarkably large share of total vehicle
sales.
(A) but sales this past November, even when
compared with sales in previous Novembers,
(B) but even when it is compared with previous
Novembers, this past November’s sales
(C) but even when they are compared with previous
Novembers, sales of light trucks this past
November
(D) so that compared with previous Novembers,
sales of light trucks this past November
(E) so that this past November’s sales, even
compared with previous Novembers’ sales,
Logical predication; Agreement
is sentence identi es November as traditionally
being the month with the strongest sales of light
trucks, and then goes on to indicate that even
when compared to previous Novembers, this past
November’s sales accounted for a notably large
portion of overall sales. It makes sense to make a
comparison between sales in one November with
sales in other Novembers. It does not make sense
to compare sales to months, as in (C) and (D).
A Correct. is version makes the correct
comparison between sales in one particular
November and sales in previous Novembers.
B e antecedent of the word it is unclear. e
sentence begins with the word November ,
which is used to refer not to a speci c
November, but to the month generally. If
the antecedent of it is taken to be November ,
then the sentence compares November,
taken generally, to previous Novembers. But
previous to what? Since taking November
to be the antecedent renders the sentence
nonsensical, we may be inclined to look for
the antecedent elsewhere; the only other
possible candidate, however, is this past
November’s sales , which is ruled out because
it is singular and sales is plural.
C e antecedent of the pronoun they is sales ,
making the comparison between they and
previous Novembers illogical.
D e sentence illogically compares sales
of light trucks with previous Novembers.
e conjunction so that nonsensically
introduces a causal relationship between
November’s typically strong sales and the
aforementioned comparison.
E Like (D), this sentence introduces a
nonsensical causal relationship, in this case
between the fact that November typically
has the strongest sales and the fact that
this past November’s sales accounted for a
remarkably large share of total vehicle sales.
e correct answer is A.
784. Most of the country’s biggest daily newspapers had
lower circulation in the six months from October 1995
through March 1996 than a similar period a year
earlier.
(A) a similar period
(B) a similar period’s
(C) in a similar period
(D) that in a similar period
(E) that of a similar period
![](asset-30e.png)
775
Logical Predication; Parallelism
e sentence compares newspaper circulation
during two separate periods, but the comparison
is not parallel because it has been drawn using a
prepositional phrase, in the six months, and a noun
phrase, a similar period. Both phrases compared
by than should be prepositional phrases: lower in
the six months ... than in a similar period.
A In the six months and a similar period are not
grammatically parallel. e sentence appears
illogically to compare a period of time with
an amount of circulation.
B In the six months and a similar period’s are
not grammatically parallel.
C Correct. In the six months and in a similar
period are both prepositional phrases,
making the comparison clear and properly
idiomatic.
D In the six months and that in a similar period
are not grammatically parallel; it is unclear
what the antecedent of that is supposed to
be.
E In the six months and that of a similar period
are not grammatically parallel; it is unclear
what the antecedent of that is supposed to be.
e correct answer is C.
785. Mauritius was a British colony for almost 200 years,
excepting for the domains of administration and
teaching, the English language was never really spoken
on the island.
(A) excepting for
(B) except in
(C) but except in
(D) but excepting for
(E) with the exception of
Idiom; Grammatical construction
is two‐clause sentence describes an apparent
incompatibility: as a British colony, Mauritius
might be expected to be English‐speaking, but
in fact it was not. To describe this apparent
contradiction and to avoid a comma splice, the
clauses should be joined by the conjunction but.
Domains describes places in which English is
spoken; for is the incorrect preposition. Excepting
is not idiomatic English in this case.
A e lack of a conjunction causes a comma
splice; excepting for is non‐idiomatic.
B e lack of a conjunction causes a comma
splice.
C Correct. e two independent clauses
are separated by but , and except in is an
appropriate idiom.
D Excepting for is non‐idiomatic.
E e lack of a conjunction causes a comma
splice.
e correct answer is C.
786. Although appearing less appetizing than most of
their round and red supermarket cousins, heirloom
tomatoes, grown from seeds saved during the previous
year—they are often green and striped, or have plenty
of bumps and bruises—heirlooms are more avorful
and thus in increasing demand.
(A) Although appearing less appetizing than most
of their round and red supermarket cousins,
heirloom tomatoes, grown from seeds saved
during the previous year
(B) Although heirloom tomatoes, grown from seeds
saved during the previous year, appear less
appetizing than most of their round and red
supermarket cousins
(C) Although they appear less appetizing than most
of their round and red supermarket cousins,
heirloom tomatoes, grown from seeds saved
during the previous year
(D) Grown from seeds saved during the previous
year, heirloom tomatoes appear less appetizing
than most of their round and red supermarket
cousins
(E) Heirloom tomatoes, grown from seeds saved
during the previous year, although they appear
less appetizing than most of their round and red
supermarket cousins
Rhetorical construction; Grammatical
construction
e intended meaning could be communicated
more e ectively by mentioning heirloom
tomatoes as early as possible in the sentence,
so that we know that the writer is comparing
heirloom tomatoes with supermarket tomatoes.
e placement of heirloom tomatoes and heirlooms
makes the sentence ungrammatical.
9.8 Sentence Correction Answer Explanations
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A is is ungrammatical. If heirloom tomatoes
is the subject of are more avorful …
then heirlooms has no predicate and is
nonsensically super uous. If heirlooms is the
subject, heirloom tomatoes has no predicate.
B Correct. e noun heirloom tomatoes is
mentioned early in the sentence, followed
by a parenthetical de nition, and is the
subject of the verb appear , and heirlooms is
the subject of are.
C e noun heirloom tomatoes appears too late
in the sentence. Parsing is made harder by
introducing the pronoun they and revealing
its antecedent later in the sentence. e
sentence is also ungrammatical. If heirloom
tomatoes is the subject of are more avorful
… then heirlooms has no predicate and is
nonsensically super uous. If heirlooms is the
subject, heirloom tomatoes has no predicate.
D Beginning the sentence with the
explanatory clause grown from seeds …
gives it too much importance. It could
be construed as the reason why heirloom
tomatoes appear less appetizing, which is
contrary to the truth. e sentence is also
ungrammatical.
E Rhetorical structure requires that although
appear in the beginning of the clause to
which it pertains. Placing it later necessitates
the pronoun they with antecedent heirloom
tomatoes , which is redundant. e sentence is
also ungrammatical.
e correct answer is B.
787. The World Wildlife Fund has declared that global
warming, a phenomenon most scientists agree to be
caused by human beings in burning fossil fuels, will
create havoc among migratory birds by altering the
environment in ways harmful to their habitats.
(A) a phenomenon most scientists agree to be
caused by human beings in burning fossil fuels,
(B) a phenomenon most scientists agree that is
caused by fossil fuels burned by human beings,
(C) a phenomenon that most scientists agree is
caused by human beings’ burning of fossil fuels,
(D) which most scientists agree on as a
phenomenon caused by human beings who burn
fossil fuels,
(E) which most scientists agree to be a phenomenon
caused by fossil fuels burned by human beings,
Logical predication; Rhetorical
construction
e underlined portion of the sentence is
an appositive de ning global warming as a
phenomenon caused by the burning of fossil fuels
by humans. Because this appositive intervenes
between the subject ( global warming ) and verb
( will create ) of a clause, it should be expressed as
clearly and economically as possible so as not to
confuse the meaning of the sentence as a whole.
A To be caused and in burning are wordy,
awkward, and indirect.
B at is should immediately follow
phenomenon , not agree .
C Correct. e phrase human beings’ burning
is more economical than constructions with
prepositional phrases or relative clauses.
D e phrasing is wordy and indirect.
E e phrasing is wordy and the meaning is
imprecise; it is not fossil fuels that cause
global warming—it is the burning of fossil
fuels by humans.
e correct answer is C.
788. The largest of all the planets, not only is Jupiter three
times so massive as Saturn, the next larger planet, but
also possesses four of the largest satellites, or moons,
in our solar system.
(A) not only is Jupiter three times so massive as
Saturn, the next larger
(B) not only is Jupiter three times as massive as
Saturn, the next largest
(C) Jupiter, not only three times as massive as
Saturn, the next largest
(D) Jupiter not only is three times as massive as
Saturn, the next largest
(E) Jupiter is not only three times so massive as
Saturn, the next larger
Diction; Idiom
is sentence begins with a phrase, [ t ] he largest
. . ., describing the main subject Jupiter . e
remainder of the sentence describes Jupiter’s size
and possession of moons, using the idiom not only
x but y to introduce parallel adjective phrases.
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A In this version of the sentence, so massive as
Saturn violates the parallelism established
by the idiom as + adjective + as + noun .
For the sake of clarity, the noun described
by the opening adjectival phrase should
immediately follow that phrase. e phrase
next larger is unidiomatic and unclear. e
superlative ( largest ) is appropriate in this
consideration of all the planets.
B As in (A), Jupiter should immediately follow
the opening phrase.
C is version of the sentence violates the
parallelism of the idiom not only x but y ,
following the rst half of the template with
an adjective phrase and the second half with
a verb phrase.
D Correct. e placement of the subject
in relation to the opening modi er, the
properly constructed phrasing, and the
proper use of comparison words make the
meaning of the sentence clear.
E e phrase so massive as violates the idiom as
x as y . Consideration of Jupiter’s size among
all the planets, including Saturn, requires
the superlative form, largest .
e correct answer is D.
789. While many of the dinosaur fossils found recently
in northeast China seem to provide evidence of the
kinship between dinosaurs and birds, the wealth of
enigmatic fossils seem more likely at this stage that
they will in ame debates over the origin of birds rather
than settle them.
(A) seem more likely at this stage that they will
in ame debates over the origin of birds rather
than
(B) seem more likely that it will in ame debates over
the origin of birds at this stage than
(C) seems more likely to in ame debates on the
origin of birds at this stage rather than
(D) seems more likely at this stage to in ame
debates over the origin of birds than to
(E) seems more likely that it will in ame debates on
the origin of birds at this stage than to
Agreement; Parallelism
is sentence states that whereas many dinosaur
fossils from China suggest that there is a kinship
between dinosaurs and birds, the wealth of fossils
are more ambiguous about what they suggest about
the ancestry of birds. e word wealth is a mass
noun followed by a prepositional phrase; because
wealth follows the article the , the emphasis is on it
rather than on the noun in the prepositional phrase,
fossils . e singular wealth requires a singular main
verb ( seems ). e comparative expression more
likely . . . must be followed by an in nitive verb ( to
in ame ) so it will be parallel to the verb with which
it is compared ( to settle ).
A e singular subject wealth does not agree
with the plural verb seem ; both items
being compared should be in parallel form
( in ame and settle ); the relative clause that
they will in ame violates the parallelism.
B Again, the relative clause violates the desired
parallelism; the singular subject, wealth ,
requires a singular verb, seems .
C e subject and the verb agree with one
another, but the placement of the modi er
at this stage makes the modi er appear to
describe origin of the birds rather than the
verb seems .
D Correct. e verb seems agrees in number
with the noun wealth ; the in nitive to
in ame is parallel with the verb to which it
is compared, to settle .
E e clause wealth . . . seems more likely that
it will in ame is not idiomatic, and that it
will in ame is not parallel with the in nitive
verb to settle .
e correct answer is D.
790. Found only in the Western Hemisphere and surviving
through extremes of climate, hummingbirds’ range
extends from Alaska to Tierra del Fuego, from sea‐level
rain forests to the edges of Andean snow elds and ice
elds at altitudes of 15,000 feet.
(A) Found only in the Western Hemisphere
and surviving through extremes of climate,
hummingbirds’ range extends
(B) Found only in the Western Hemisphere,
hummingbirds survive through extremes of
climate, their range extending
9.8 Sentence Correction Answer Explanations
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GMAT® Offi cial Guide 2018
(C) Hummingbirds, found only in the Western
Hemisphere and surviving through extremes of
climate, with their range extending
(D) Hummingbirds, found only in the Western
Hemisphere and surviving through extremes of
climate, their range extends
(E) Hummingbirds are found only in the Western
Hemisphere, survive through extremes of
climate, and their range extends
Logical predication; Grammatical
construction
is sentence makes three points about
hummingbirds: they live in the Western Hemisphere,
they survive extreme climates, and their range is wide
and varied. Hummingbirds , not hummingbirds’ range ,
should be the subject of the sentence.
A e opening modi er, found . . . and
surviving . . . should modify hummingbirds ,
not, as it does, hummingbirds’ range .
B Correct. Hummingbirds is the subject of the
sentence, and the use of the absolute phrase
their range extending appropriately connects
the nal clause to the rest of the sentence.
C is version of the sentence has no main
verb for the subject Hummingbirds and as a
result is ungrammatical.
D Like (C), this version of the sentence has no
main verb for the subject Hummingbirds .
E is version of the sentence begins with the
subject Hummingbirds attached to a pair of
verb phrases ( are found . . . and survive . . . )
followed by the conjunction and , which
suggests that what follows should also
be a verb phrase; instead, a new subject
is introduced, their range . Replacing the
comma before survive with and would
render the sentence acceptable.
e correct answer is B.
791. She was less successful after she had emigrated
to New York compared to her native Germany,
photographer Lotte Jacobi nevertheless earned a small
group of discerning admirers, and her photographs
were eventually exhibited in prestigious galleries
across the United States.
(A) She was less successful after she had emigrated
to New York compared to
(B) Being less successful after she had emigrated to
New York as compared to
(C) Less successful after she emigrated to New York
than she had been in
(D) Although she was less successful after
emigrating to New York when compared to
(E) She had been less successful after emigrating to
New York than in
Idiom; Grammatical construction; Logical
predication
is sentence compares the success Jacobi
experienced after moving to New York to
the success she had previously experienced in
Germany. e phrase less successful anticipates the
conclusion of the comparison with the phrase
than. … e main subject of the sentence is
photographer Lotte Jacobi , and the main verb is
earned . e opening clause She was less successful
… therefore creates a comma splice if the comma
is not followed by a conjunction. e most
e cient way to incorporate the information
about Jacobi’s comparative successes in Germany
and in New York is to turn this clause into an
adjectival phrase describing Jacobi.
A Less successful … anticipates than rather than
compared to …; a comma is insu cient to
join two independent clauses into a single
sentence.
B As compared to is an incorrect way to
complete the comparison introduced by
less ; Being … is unnecessarily wordy and
awkward.
C Correct. e idiomatic construction less
successful … than is incorporated into an
introductory adjectival phrase modifying
Lotte Jacobi .
D When compared to is an incorrect phrase to
complete the comparison introduced by less .
E A comma is insu cient to join two
independent clauses into a single sentence;
past‐perfect tense is misleading, since it
refers to Jacobi’s experience in New York,
which in fact followed her experience in
Germany.
e correct answer is C.
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779
792. Scientists have recently found evidence that black
holes—regions of space in which matter is so
concentrated and the pull of gravity so powerful that
nothing, not even light, can emerge from them—
probably exist at the core of nearly all galaxies and
the mass of each black hole is proportional to its host
galaxy.
(A) exist at the core of nearly all galaxies and the
mass of each black hole is proportional to
(B) exist at the core of nearly all galaxies and that
the mass of each black hole is proportional to
that of
(C) exist at the core of nearly all galaxies, and that
the mass of each black hole is proportional to
(D) exists at the core of nearly all galaxies, and that
the mass of each black hole is proportional to
that of
(E) exists at the core of nearly all galaxies and the
mass of each black hole is proportional to that of
Logical predication; Agreement
is sentence focuses attention on two
hypotheses about black holes—one about their
location and the other about their mass. ese
hypotheses appear as parallel relative clauses that
black holes . . . exist at . . . and that the mass . . .
is proportional . e subject of the rst relative
clause ( black holes ) is plural, so the clause must be
completed with the plural form of exist .
A is version of the sentence does not
provide the relative pronoun that to provide
parallel structure for presenting the two
things scienti c evidence reveals about
black holes. is leaves it somewhat unclear
whether the nal clause is intended to
convey part of what the scientists discovered
or to express a claim that the writer is
making independently of the scientists’
discovery. e sentence illogically compares
mass to galaxy .
B Correct. e structure of the sentence
makes the meaning clear, and the plural verb
form agrees with the plural subject.
C e comma appears to signal that the
nal part of the sentence is intended as an
independent clause expressing a separate
claim rather than describing part of the
scientists’ discovery. But if it were intended
in that way, it should be set o as a separate
sentence, not conjoined with the preceding
clause. Like (A), this version makes an
illogical comparison between mass and
galaxy .
D e singular verb exists does not agree with
the plural subject black holes . As in (C), the
comma is inappropriate because it does not
introduce a new independent clause.
E e singular verb exists does not agree
with the plural subject black holes . Like
(A), this version lacks the relative pronoun
that , which would clarify the relationship
between the two clauses.
e correct answer is B.
793. The use of lie detectors is based on the assumption
that lying produces emotional reactions in an individual
that, in turn, create unconscious physiological
responses.
(A) that, in turn, create unconscious physiological
responses
(B) that creates unconscious physiological
responses in turn
(C) creating, in turn, unconscious physiological
responses
(D) to create, in turn, physiological responses that
are unconscious
(E) who creates unconscious physiological
responses in turn
Agreement; Rhetorical construction;
Logical predication
is sentence describes a cause‐and‐e ect
sequence; in the underlined portion of the
sentence, the relative pronoun that refers to the
plural noun reactions. e verb in the relative
clause must therefore be a plural verb. e causal
sequence is most clearly expressed by a relative
clause that turns the object emotional reactions
(from the clause lying causes emotional reactions
in an individual ) into the subject ( that ) of a new
clause ( that in turn create unconscious physiological
responses ) . In turn is best placed before the verb of
the second relative clause, create , to clarify that a
chain of events is being described.
9.8 Sentence Correction Answer Explanations
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A Correct. is construction clearly indicates
the causal sequence.
B e singular verb creates does not agree
with the subject referenced by the relative
pronoun that ( reactions ).
C is construction is less successful at
clarifying the chain of events because
creating seems to refer back to lying ; if used
as a participial, creating would have to be
preceded by a comma.
D is construction does not make clear the
causal chain of events, because it is unclear
which noun to create should attach to; the
in nitive construction implies intent, which
does not really make sense.
E Because reactions is not a person, who is the
wrong relative pronoun to use.
e correct answer is A.
794. Australian embryologists have found evidence that
suggests that the elephant is descended from an
aquatic animal, and its trunk originally evolving as a
kind of snorkel.
(A) that suggests that the elephant is descended
from an aquatic animal, and its trunk originally
evolving
(B) that has suggested the elephant descended from
an aquatic animal, its trunk originally evolving
(C) suggesting that the elephant had descended
from an aquatic animal with its trunk originally
evolved
(D) to suggest that the elephant had descended
from an aquatic animal and its trunk originally
evolved
(E) to suggest that the elephant is descended from
an aquatic animal and that its trunk originally
evolved
Parallelism; Verb form
e clearest, most economical way of expressing
the two things suggested by Australian
embryologists’ evidence is to format them as
relative clauses serving as parallel direct objects
of the verb suggest. It is awkward and confusing
to string together relative clauses: evidence that
suggests that the elephant. … A clearer way of
making this connection is to turn the verb suggests
into a participle modifying evidence. e word
descended is a predicate adjective following the
present‐tense verb is and describing the present‐
day elephant. e verb evolved should be past
tense because it describes how the trunk of the
elephant originally evolved, not how it is evolving
today.
A e string of relative phrases is awkward
and confusing; the phrase following
the conjunction and is not parallel with
the relative clause that the elephant is
descended. …
B e evidence still suggests these things about
the evolution of the elephant and its trunk, so
the present‐perfect verb tense is inaccurate.
C Had descended is the wrong verb tense; with
cannot be followed by an independent clause.
D Had descended is the wrong tense; the phrase
following the conjunction and does not
parallel the relative clause that precedes the
conjunction.
E Correct. e two dependent clauses
beginning with that are in parallel form and
contain verbs in the correct tenses.
e correct answer is E.
795. Most efforts to combat such mosquito‐borne diseases
like malaria and dengue have focused either on the
vaccination of humans or on exterminating mosquitoes
with pesticides.
(A) like malaria and dengue have focused either on
the vaccination of humans or on exterminating
(B) like malaria and dengue have focused either on
vaccinating of humans or on the extermination of
(C) as malaria and dengue have focused on either
vaccinating humans or on exterminating
(D) as malaria and dengue have focused on either
vaccinating of humans or on extermination of
(E) as malaria and dengue have focused on either
vaccinating humans or exterminating
Diction; Parallelism
e phrase such … diseases like malaria and dengue
is not a correct way in English to indicate that the
two diseases mentioned are examples of a larger
category; the correct expression is such … as. …
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A is use of such … like … is incorrect English;
the correct expression is such … as.… It is
better to keep the preposition on close to the
verb it goes with, focus , so as not to repeat it.
B e correct expression is such … as.… It is
better to keep the preposition on close to the
verb it goes with, focus , so as not to repeat it.
is use of the gerund vaccinating (followed
by of ) would normally be preceded by the ,
but this would make the phrase awkward.
It would be preferable to use vaccination ,
which is parallel to extermination .
C is answer choice incorrectly repeats the
preposition on before exterminating.
D is answer choice incorrectly repeats the
preposition on before extermination. is use
of the gerund vaccinating (followed by of )
would normally be preceded by the , but this
would make the phrase awkward. It would
be preferable to use vaccination , which is
parallel to extermination .
E Correct. is version uses either … or …
correctly and appropriately uses the parallel
forms vaccinating and exterminating .
e correct answer is E.
796. Among the Tsonga, a Bantu-speaking group of tribes
in southeastern Africa, dance teams represent
their own chief at the court of each other, providing
entertainment in return for food, drink, and lodging.
(A) the court of each other, providing entertainment
in return for
(B) the court of another and provide entertainment in
return for
(C) the court of the other, so as to provide
entertainment as a return on
(D) each other’s court, entertainment being provided
in return for
(E) another’s court and provide entertainment as a
return on
Diction; Idiom
e point of the sentence is that dancers
representing one chief perform at the court of
another chief in return for gifts. e court of each
other is unidiomatic and unclear. It could be
intended to indicate, somewhat implausibly, that
each team has a court that the other teams visit,
but represent their own chief strongly suggests that
the court referred to is the court of another chief.
e correct pronoun to refer to a di erent chief is
another.
A e court of each other is unidiomatic and
unclear. Each other seems to refer, somewhat
illogically, to the dancers.
B Correct. e sentence clearly explains the
idea, using the correct pronoun another and
the correct idiom in return for.
C is could be confusing in that the other
indicates that there is only one other chief,
whereas group of tribes suggests that there
may be a number of chiefs. As a return on
is the incorrect idiom; a return on normally
refers to a gain from an investment, not a
direct exchange of one good for another.
D Each other’s court somewhat illogically
indicates that the dancers each have a court.
Entertainment being provided in return for is
awkward and indirect.
E As a return on is the incorrect idiom; a
return on normally refers to a gain from an
investment, not a direct exchange of one
good for another.
e correct answer is B.
797. Almost like clones in their similarity to one another, the
cheetah species’ homogeneity makes them especially
vulnerable to disease.
(A) the cheetah species’ homogeneity makes them
especially vulnerable to disease
(B) the cheetah species is especially vulnerable to
disease because of its homogeneity
(C) the homogeneity of the cheetah species makes it
especially vulnerable to disease
(D) homogeneity makes members of the cheetah
species especially vulnerable to disease
(E) members of the cheetah species are especially
vulnerable to disease because of their
homogeneity
9.8 Sentence Correction Answer Explanations
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GMAT® Offi cial Guide 2018
Agreement; Logical predication
Genetic homogeneity is presented as a cause of
cheetahs’ vulnerability to disease. e opening
adjectival phrase refers to the fact that individual
cheetahs are almost like clones of one another
because of how genetically similar they are. is
adjectival phrase should be followed by what it
describes, individual cheetahs. But the structure
of the sentence makes it seem that this adjectival
phrase is meant—illogically—to describe the
cheetah species’ homogeneity . e sentence structure
also fails to make clear that the intended
reference is to just one (the only) cheetah species.
A e sentence nonsensically presents the
opening phrase as describing homogeneity .
B e resulting sentence opens with a
reference to a plurality of individuals ( to one
another ), but confusingly identi es this with
a single (collective) entity, a species.
C e resulting sentence nonsensically
presents the opening phrase as describing
homogeneity .
D e resulting sentence nonsensically
presents the opening phrase as describing
homogeneity .
E Correct. e sentence is clear and the
opening phrase correctly modi es members
of the cheetah species .
e correct answer is E.
798. As sources of electrical power, windmills now account
for only about 2,500 megawatts nationwide, but
production is almost expected to double by the end
of the year, which would provide enough electricity for
1.3 million households.
(A) almost expected to double by the end of the
year, which would provide
(B) almost expected that it will double by the end of
the year, thus providing
(C) expected that it will almost double by the end of
the year to provide
(D) expected almost to double by the end of the
year and thus to provide
(E) expected almost to double by the end of the
year, which would thus be providing
Rhetorical construction; Idiom
e intended meaning of the sentence seems to
be that the electricity production of windmills
is expected to approximately double by year’s
end. But instead of saying almost double , we have
almost expected , which is an unclear idea. Also
unclear is what the relative pronoun which refers
to.
A e placement of almost makes it
nonsensically modify is expected . What
the relative pronoun which refers to is
ambiguous: for example, does it refer to the
expectation, the possible doubling, or the
year?
B e resulting sentence misplaces the adverb
almost .
C e phrase production is expected that it
will . . . makes no sense—as opposed to, for
example, it is expected that production will. . . .
D Correct. is sentence clearly conveys the
expectations of production: almost to double
and thus to provide . ere is no ambiguity as
to what will be providing enough electricity .
E e referent of the relative pronoun which
is ambiguous, and the conditional verb form
would thus be providing is unnecessarily
wordy.
e correct answer is D.
799. While most of the earliest known ball courts in
Mesoamerica date to 900–400 B.C., waterlogged
latex balls found at El Manati and representations of
ballplayers painted on ceramics found at San Lorenzo
attest to the fact that the Mesoamerican ballgame was
well established by the mid-thirteenth century B.C.
(A) waterlogged latex balls found at El Manati
and representations of ballplayers painted on
ceramics found at San Lorenzo attest
(B) waterlogged latex balls found at El Manati and
the painting of representations of ballplayers on
ceramics found at San Lorenzo attests
(C) waterlogged latex balls found at El Manati
and ceramics painted with representations of
ballplayers found at San Lorenzo attests
(D) the nding of waterlogged latex balls at El Manati
and the painting of representations of ballplayers
on ceramics found at San Lorenzo attests
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(E) the nding of waterlogged latex balls at El Manati
and of representations of ballplayers painted on
ceramics at San Lorenzo attest
Logical predication; Agreement
e sentence points out two pieces of evidence
that prove the early existence of ballgames
in Mesoamerica: waterlogged latex balls and
representations of ballplayers. e two noun phrases
together serve as subjects for the verb attest,
creating a sentence that logically and correctly
expresses its main idea.
A Correct. Waterlogged latex balls and
representations of ballplayers together serve as
subjects for the verb attest.
B Painting could refer to something that has
been painted, but on that interpretation the
sentence does not make sense, because the
painting is itself the representation and a
single painting would not plausibly be on
multiple ceramics. Alternatively, it could
refer to an ongoing act of painting, which
could not plausibly constitute the kind of
evidence referred to. e singular verb attests
does not agree with the compound subject
balls and painting.
C e singular verb attests does not agree with
the compound subject balls and ceramics.
D Balls, not nding, should be the subject of
the verb since the balls are the evidence.
Painting could refer to something that has
been painted, but on that interpretation the
sentence does not make sense, because the
painting is itself the representation and a
single painting would not plausibly be on
multiple ceramics. Alternatively, it could
refer to an ongoing act of painting, which
could not plausibly constitute the kind of
evidence referred to. e singular verb attests
does not agree with the compound subject
nding and painting.
E Balls and representations should be the
subject of the verb attest since they are the
evidence—not nding; the plural verb attest
does not agree with the singular subject
nding.
e correct answer is A.
800. As criminal activity on the Internet becomes more and
more sophisticated, not only are thieves able to divert
cash from company bank accounts, they can also pilfer
valuable information such as business development
strategies, new product speci cations, and contract
bidding plans, and sell the data to competitors.
(A) they can also pilfer valuable information such as
business development strategies, new product
speci cations, and contract bidding plans, and
sell
(B) they can also pilfer valuable information that
includes business development strategies, new
product speci cations, and contract bidding
plans, and selling
(C) also pilfering valuable information including
business development strategies, new product
speci cations, and contract bidding plans, selling
(D) but also pilfer valuable information such as
business development strategies, new product
speci cations, and contract bidding plans to sell
(E) but also pilfering valuable information such as
business development strategies, new product
speci cations, and contract bidding plans and
selling
Grammatical construction; Verb form
e two clauses in this not only . . . construction
normally require subjects, which this sentence
has. e second clause (beginning with they can )
further divides into two clauses about pilfering and
selling; here, the two verbs must have the same
form, since each one is the main verb of its clause.
A Correct. ey supplies the needed subject,
and pilfer and sell are both in the bare verb
form.
B Selling is the wrong form for the main verb
of a nite clause; it should be sell .
C ere is no subject for the pilfer clause, and
pilfering would be the wrong form even if a
subject were added.
D ere is no subject for the pilfer clause.
E ere is no subject for the pilfer clause, and
both selling and pilfering have the wrong
verb for the main verb of a nite clause;
they should be sell and pilfer , respectively.
e correct answer is A.
9.8 Sentence Correction Answer Explanations
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801. Last week local shrimpers held a news conference to
take some credit for the resurgence of the rare Kemp’s
ridley turtle, saying that their compliance with laws
requiring that turtle‐excluder devices be on shrimp nets
protect adult sea turtles.
(A) requiring that turtle‐excluder devices be on
shrimp nets protect
(B) requiring turtle‐excluder devices on shrimp nets
is protecting
(C) that require turtle‐excluder devices on shrimp
nets protect
(D) to require turtle‐excluder devices on shrimp nets
are protecting
(E) to require turtle‐excluder devices on shrimp nets
is protecting
Rhetorical construction; Agreement
e subject of the clause introduced by saying
that is the singular noun compliance . is subject
requires the singular form of the verb protect. e
clearest, most economical way to describe the
laws in question is to follow the word laws with
a present participle requiring . To use an in nitive,
to require , seems to indicate that requiring these
devices is the objective of the laws, when in fact
the objective is to protect the sea turtles.
A e plural verb protect does not agree with
the singular subject compliance .
B Correct. e singular verb is protecting
agrees with the singular subject compliance ,
and the participial phrase beginning with
requiring concisely and accurately describes
the laws.
C e relative clause that require introduces
unnecessary wordiness; the plural verb
protect does not agree with the singular
subject compliance .
D To require obscures the purpose of the laws;
the plural verb phrase are protecting does not
agree with the singular subject compliance .
E To require obscures the purpose of the laws.
e correct answer is B.
802. A ruined structure found at Aqaba, Jordan, was
probably a church, as indicated in its eastward
orientation and by its overall plan, as well as artifacts,
such as glass oil‐lamp fragments, found at the site.
(A) A ruined structure found at Aqaba, Jordan, was
probably a church, as indicated in its eastward
orientation and by its overall plan, as well as
(B) A ruined structure found at Aqaba, Jordan, once
probably being a church, was indicated by its
eastward orientation, overall plan, and
(C) Indicating that a ruined structure found at Aqaba,
Jordan, was probably a church were its eastward
orientation and overall plan, but also the
(D) A ruined structure found at Aqaba, Jordan, was
probably a church, as indicates its eastward
orientation and overall plan, as well as the
(E) That a ruined structure found at Aqaba, Jordan,
was probably a church is indicated by its
eastward orientation and overall plan, as well as
by the
Logical predication; Parallelism
is sentence explains why a currently ruined
structure probably used to be a church. In the
best‐worded answer choice, the abstract subject
(the probability that a certain hypothesis is true)
is explained abstractly in a relative clause ( at
a ruined structure was probably . . . ) followed
by a passive verb ( is indicated ), followed by the
prepositional phrase ( by . . . ), which is completed
by a parallel listing of forms of evidence, all
presented as noun phrases in the expression, ( by )
(its) A + B, as well as ( by ) C.
A is version makes the relationship between
as well as . . . and the rest of the sentence
unclear. e most plausible hypothesis is
that the artifacts are another of the types
of evidence, parallel with the structure’s
orientation and its plan. e sentence
violates the parallelism required in the list
by failing to supply the preposition in the
nal item following as well as .
B e subject of this version of the sentence,
structure , is completed by the verb was
indicated , creating the illogical assertion that
the structure itself, rather than its probable
identity, was indicated by its orientation,
plan, and attendant artifacts.
C Opening the sentence with the predicate
adjective indicating leads to a confusing
and awkward withholding of the subjects
orientation . . . plan . . . artifacts .
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9.8 Sentence Correction Answer Explanations
D e only plausible subject for the singular
verb indicates is the plural orientation . . . plan,
as well as the artifacts . Very little about this
sentence makes sense.
E Correct. e relationships among the parts
of the sentence are clear and logical.
e correct answer is E.
803. In the major cities of industrialized countries at the
end of the nineteenth century, important public places
such as theaters, restaurants, shops, and banks had
installed electric lighting, but electricity was in less than
1 percent of homes, where lighting was still provided
mainly by candles or gas.
(A) electricity was in less than 1 percent of homes,
where lighting was still
(B) electricity was in less than 1 percent of homes
and lighting still
(C) there had been less than 1 percent of homes with
electricity, where lighting was still being
(D) there was less than 1 percent of homes that had
electricity, having lighting that was still
(E) less than 1 percent of homes had electricity,
where lighting had still been
Rhetorical construction; Verb form
In this type of usage, a participle such as provided
normally must be preceded by some form of the
verb be . e best choice for this is the past tense
was , since the main part of the clause describes the
situation in the past tense ( electricity was . . .). To
link the ideas of lighting and electricity in homes,
where is the most e cient and direct expression,
superior to alternatives such as and or having .
A Correct. e participle is preceded by the
appropriate form was , and the clauses are
linked e ciently by where .
B ere is no form of be in the second clause,
and and does not clearly indicate the
connection between the two clauses.
C Had been and was being represent
inappropriate tenses, and the there had been
construction is longer than necessary.
D Both having lighting and the there was
construction are longer and more complicated
than necessary. is sentence structure makes
there , instead of homes , the subject of having .
E Had been is not the appropriate tense for this
situation.
e correct answer is A.
804. By 1999, astronomers had discovered 17 nearby stars
that are orbited by planets about the size of Jupiter.
(A) had discovered 17 nearby stars that are orbited
by planets
(B) had discovered 17 nearby stars with planets
orbiting them that were
(C) had discovered that there were 17 nearby stars
that were orbited by planets
(D) have discovered 17 nearby stars with planets
orbiting them that are
(E) have discovered that 17 nearby stars are orbited
by planets
Verb form; Rhetorical construction
Opening with a past date ( 1999 ) describing the
end point of a period of discovery, this sentence
calls for a past perfect main verb to follow the
subject astronomers . In order to economize on
words and maximize clarity, the object of the main
clause, stars , is modi ed by a passive relative clause
that are orbited by planets followed by the adjective
phrase about the size of Jupiter . is structure avoids
an awkward and confusing string of relative clauses
and prepositional phrases.
A Correct. is version is clear and uses the
correct verb form had discovered .
B e use of a prepositional phrase with planets
necessitates the introduction of a relative clause
that were . . ., in which the referent of the
relative pronoun that is somewhat uncertain
(stars? or planets?). e past tense verb were
suggests, improbably, that the size of the planets
may have changed signi cantly since 1999.
C e string of relative clauses is awkward and
wordy.
D If the sentence was written after 1999, the
present perfect tense is illogical, because 1999
is in the past. If it was written in 1999, this
way of referring to the then‐present time is
odd and misleading. e prepositional phrase
is wordy and indirect.
E As in (D), the present perfect tense is illogical.
e correct answer is A.
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805. Although she was considered among her
contemporaries to be the better poet than her
husband, later Elizabeth Barrett Browning was
overshadowed by his success.
(A) Although she was considered among her
contemporaries to be the better poet than her
husband, later Elizabeth Barrett Browning was
overshadowed by his success.
(B) Although Elizabeth Barrett Browning was
considered among her contemporaries as a
better poet than her husband, she was later
overshadowed by his success.
(C) Later overshadowed by the success of her
husband, Elizabeth Barrett Browning’s poetry had
been considered among her contemporaries to
be better than that of her husband.
(D) Although Elizabeth Barrett Browning’s success
was later overshadowed by that of her husband,
among her contemporaries she was considered
the better poet.
(E) Elizabeth Barrett Browning’s poetry was
considered among her contemporaries as better
than her husband, but her success was later
overshadowed by his.
Idiom; Verb form; Logical predication
e sentence misuses the locution the better poet .
It is acceptable to say a better poet than but not
the better poet than . If you have already mentioned
two poets X and Y , and you want to say that X is
better than Y , you can either say X is a better poet
than Y , or simply , X is the better poet.
A is version of the sentence misuses the
idiom the better poet , most likely confusing it
with the idiom a better poet than .
B [W] as considered among her contemporaries
as is awkward and unnecessarily creates a
potential misreading (she was considered to
be among her contemporaries).
C e subject here is Elizabeth Barrett
Browning’s poetry , not Elizabeth Barrett
Browning , so the antecedent of her in
her husband could comically be taken to
be Elizabeth Barrett Browning’s poetry .
Furthermore, the tense of had been considered
pairs oddly with Later overshadowed . Each
seems to be in reaction to some particular time
T —later than T and earlier than T , but when
T was or its signi cance is never indicated.
D Correct. is version avoids the problems
of the other versions.
E is sentence comically compares Elizabeth
Barrett Browning’s poetry to her husband.
e correct answer is D.
806. In no other historical sighting did Halley’s Comet
causesuch a worldwide sensation as did its return in
1910–1911.
(A) did its return in 1910–1911
(B) had its 1910–1911 return
(C) in its return of 1910–1911
(D) its return of 1910–1911 did
(E) its return in 1910–1911
Parallelism; Verb form; Logical predication
e single subject of this sentence is Halley’s
Comet , and its single verb phrase is did cause.
e comparison presented by the sentence is
between adverbial phrases describing times when
the comet was seen. Grammatically, the items
being compared are parallel prepositional phrases
beginning with the preposition in: in no other
sighting and in its return in 1910–1911 . is is the
clearest, most economical way of presenting the
information. e options that introduce a second
verb ( did or had ) violate the parallelism and
introduce a comparison between the comet itself
(subject of the verb did cause ) and the comet’s
return (subject of the verb did or had ).
A is sentence implies a comparison between
the comet and its return.
B is sentence implies a comparison between
the comet and its return; had is the wrong
auxiliary verb form because it must be
followed by caused instead of cause .
C Correct. e parallel prepositional phrases
in this sentence correctly compare times
when the comet was sighted.
D is sentence implies a comparison between
the comet and its return.
E is sentence violates parallelism, implying
a comparison between a prepositional
phrase and a noun phrase.
e correct answer is C.
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807. Rock samples taken from the remains of an asteroid
about twice the size of the 6‐mile‐wide asteroid that
eradicated the dinosaurs has been dated to be 3.47
billion years old and thus is evidence of the earliest
known asteroid impact on Earth.
(A) has been dated to be 3.47 billion years old and
thus is
(B) has been dated at 3.47 billion years old and thus
(C) have been dated to be 3.47 billion years old and
thus are
(D) have been dated as being 3.47 billion years old
and thus
(E) have been dated at 3.47 billion years old and
thus are
Agreement; Idiom
e plural subject of this sentence, Rock samples ,
requires plural verb phrases— have been dated
and are rather than has been dated and is. e
idiomatic way of expressing estimation of age is
with the phrase dated at.
A e subject and verbs do not agree; dated to
be … is not idiomatic.
B e subject and verb do not agree; the
conjunction and thus should be followed by
a verb.
C Dated to be is not idiomatic.
D As being is not idiomatic; the conjunction
and thus should be followed by a verb.
E Correct. e plural verbs match the plural
subject, and the wording of the sentence is
idiomatic.
e correct answer is E.
9.8 Sentence Correction Answer Explanations
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10.0 Integrated Reasoning
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10.0 Integrated Reasoning
10.0 Integrated Reasoning
e Integrated Reasoning section measures your ability to understand and evaluate multiple sources
and types of information—graphic, numeric, and verbal—as they relate to one another; use quantitative
and verbal reasoning to solve complex problems; and solve multiple problems in relation to one another.
is section includes text passages, tables, graphs, and other visual information from a variety of content
areas; however, the materials and questions do not assume detailed knowledge of the topics discussed.
e Integrated Reasoning section di ers from the Quantitative and Verbal sections in two important
ways: 1) It involves both mathematical and verbal reasoning, either separately or in combination,
and 2) questions are answered using four di erent response formats rather than only traditional
multiple‐choice.
Four types of questions are used in the Integrated Reasoning section:
• Multi‐Source Reasoning
• Table Analysis
• Graphics Interpretation
• Two‐Part Analysis
Use your unique access code found in the back of this book to access 50 additional Integrated
Reasoning practice questions with full answer explanations.
10.1 What Is Measured
Integrated Reasoning questions assess your ability to apply, evaluate, infer, recognize, and strategize.
Apply concepts presented in the information
Apply questions measure your ability to understand principles, rules, or other concepts in the
information provided and apply them to a new context or predict consequences that would follow if
new information were incorporated into the context provided. You may be asked to
• decide whether new examples would comply with or violate rules established in the
information provided
• determine how a trend present in the information provided would be a ected by new scenarios
• use principles established in the information provided to draw conclusions about new data
Evaluate information qualitatively
Evaluate questions measure your ability to make judgments about the quality of information. For
example, you may be asked to
• decide whether a claim made in one source is supported or undermined by information provided
in another source
• determine whether the information provided is su cient to justify a course of action
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GMAT® Offi cial Guide 2018
• judge the strength of evidence o ered in support of an argument or plan
• identify errors or gaps in the information provided
Draw inferences from the information
Infer questions ask about information or ideas that are not explicitly stated in the materials provided but
can be derived from them. For example, you may be asked to
• calculate the probability of an outcome on the basis of given data
• indicate whether statements follow logically from the information provided
• determine the meaning of a term within the context in which it is used
• identify the rate of change in data gathered over time
Recognize parts or relationships in the information
Recognize questions measure your ability to identify information that is directly presented in the
materials provided, including speci c facts or details and relationships between pieces of information.
For example, you may be asked to
• identify areas of agreement and disagreement between sources of information
• determine the strength of correlation between two variables
• indicate which element in a table has a given rank in a combination of categories
• identify facts provided as evidence in an argument
Make strategic decisions or judgments based on the information
Strategize questions ask about the means of achieving a goal within the context of particular needs or
constraints. For example, you may be asked to
• choose a plan of action that minimizes risks and maximizes value
• identify tradeo s required to reach a goal
• specify the mathematical formula that will yield a desired result
• determine which means of completing a task are consistent within given constraints
10.2 The Question Types
e four Integrated Reasoning question types are described in detail below.
Multi-Source Reasoning
Multi‐Source Reasoning questions begin with two or three sources of information, each labeled with a
tab, which appear on the left side of a split computer screen. One or more of the sources will contain a
written passage. e other sources may be tables, graphs, diagrams, or other types of visual information.
Only one source of information will be displayed at a time. To view a di erent source, select its tab from
those that appear above the source which is currently displayed.
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10.2 Integrated Reasoning The Question Types
e sources of information are accompanied by questions that will ask you to synthesize, compare,
interpret, or apply the information presented. As each question associated with the sources appears in
turn on the right side of the screen, the initial source will appear again on the left side. You can click on
the tabs to view any of the sources as many times as needed. However, you will see only one question at
a time and cannot go back to earlier questions.
ere are two question formats for Multi‐Source Reasoning:
• Multiple‐choice questions
• Multiple‐dichotomous choice questions
For multiple‐choice questions, select the best of the ve answer choices given. Read each question and
series of answer choices carefully. Make sure you understand exactly what the question is asking and
what the answer choices are.
Multiple‐dichotomous choice questions provide three phrases, statements, numerical values, or algebraic
expressions that require an indication as to whether each meets a certain condition. For example, you
may be asked whether
• each statement is true, according to the sources
• each statement or numerical value is consistent with the sources
• each statement or algebraic expression would solve a problem described in the sources
• the value of each algebraic expression can be determined on the basis of the sources
In answering both kinds of Multi‐Source Reasoning questions, be aware of the information from each
source provided and try to determine the process that works best for you. One strategy is to examine
the sources carefully and thoroughly, another is to skim the sources the rst time through, or to read the
rst question before examining the sources. Read each question carefully and make sure you understand
exactly what the question is asking. If necessary, go back to the sources to review relevant information.
You will have 30 minutes to complete the Integrated Reasoning section, or an average of 2 minutes and
30 seconds to answer each multiple‐choice or multiple‐dichotomous choice question. Keep in mind that
you will need time to examine the source materials that accompany the questions—and that this time
must be factored into the per‐question average.
Table Analysis
Table Analysis questions present a table similar to a spreadsheet. It can be sorted on any of its columns
by selecting the column’s title from a drop‐down menu. ere may be a brief text explaining the table
or providing additional information. e question then presents three phrases, statements, numerical
values, or algebraic expressions, and you must indicate for each one whether or not it meets a certain
condition. For example, you may be asked whether
• each statement is true (yes or no), according to the information in the table
• each statement or numerical value is consistent or inconsistent with the information in the table
• each statement or numerical value can or cannot be determined on the basis of the information in
the table
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Read the question thoroughly to make sure you understand what is being asked. en consider each
phrase, statement, numerical value, or algebraic expression to learn what information in the table you
need to make your decision. For example, in analyzing the table, you may need to,
• determine statistics such as mean, median, mode, or range
• determine ratios, proportions, or probabilities
• identify correlations between two sets of data
• compare an entry’s rank in two or more of the table’s categories
You will have 30 minutes to complete the Integrated Reasoning section, or an average of 2 minutes and
30 seconds to answer each question. Keep in mind that each Table Analysis question has three parts
that all need to be answered in the time allowed.
Graphics Interpretation
Graphics Interpretation questions present a graph, diagram, or other visual representation of
information, followed by one or more statements containing a total of two blanks. e blanks should be
lled in with the option from each drop‐down menu in order to create the most accurate statement or
statements on the basis of the information provided.
Many of the graphs included in Graphics Interpretation questions involve two variables plotted on
vertical and horizontal axes. Graphs of this type include bar graphs, line graphs, scatterplots, and bubble
graphs . To read these graphs, determine what information is represented on each axis. Do this by
carefully examining any information that may be provided, including labels on the axes, scales on the
axes, the title of the graph, and accompanying text. To nd the value of a data point on the graph,
determine the corresponding values on the horizontal and vertical axes.
In the simple bar graph below, the rst bar indicates that 7 units were sold on Monday of Week 1.
10
Monday
Tuesday
Wednesday
ursday
Friday
Units Sold in Week 1
Units Sold
8
6
4
2
0
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e same information is presented below as a line graph. Each point indicates the total number of units
sold on a given day. e slope of the line connecting the points shows how the sales changed over time;
a positive slope indicates that sales increased from the previous day, and a negative slope indicates that
sales decreased.
10
Monday
Tuesday
Wednesday
ursday
Friday
Units Sold in Week 1
Units Sold
8
6
4
2
0
10
Monday
Tuesday
Wednesday
ursday
Friday
Units Sold in Week 1
Units Sold
percent of total
8
6
4
2
0
30
24
18
12
6
0
units sold
percent of total
A third variable can be indicated with an additional vertical axis. In the following graph, the bars
indicate the number of units sold on each day, which corresponds to the scale on the left axis. e line
graph shows what percent of the total units were sold on each day. e scale for the percentages is
shown on the right axis.
In a scatterplot , each dot is a single data point. In the scatterplot at the top of the next page, each dot
represents a type of computer product available for purchase. A dot’s position relative to the vertical axis
indicates the product’s price, and its position relative to the horizontal axis indicates its weight. us,
the product that weighs 1.0 kg costs approximately 32,000 rupees.
10.2 Integrated Reasoning The Question Types
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Some scatterplots include a trend line —usually a least squares regression line —that shows the trend of
the data. A trend line with positive slope indicates a positive correlation between the two variables,
and a trend line with negative slope indicates a negative correlation. us, in the scatterplot below,
the trend line indicates a negative correlation between price and weight among the products
represented on the graph. e closer the data points are to a trend line, the more strongly the data are
correlated.
In a bubble graph , each data point is represented by a circle. e center of the circle indicates the
values on the horizontal and vertical axes, as in a scatterplot. e relative size of a circle introduces a
third variable, number sold. In the bubble graph below, the relative size of the circles indicates how
many of the products were sold. us, the number of the lightest product sold was smaller than that
of any other product shown, and the number of the heaviest product sold was greater than that of any
other product shown.
35,000
weight in kg
price in rupees
Products for Sale by Price and Weight
30,000
25,000
20,000
15,000
10,000
2.52.01.51.00.5 3.0
35,000
weight in kg
price in rupees
Products for Sale by Price and Weight
30,000
25,000
20,000
15,000
10,000
2.52.01.51.00.5 3.0
35,000
weight in kg
price in rupees
Products for Sale by Price, Weight, and Number Sold
30,000
25,000
20,000
15,000
1.71.51.31.10.9 1.9
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Other common kinds of graphics do not use vertical and horizontal axes. ese include pie charts, ow
charts , and organization charts .
A pie chart uses a circle divided into sectors to show what percent of the whole is represented by each
component part. e circle represents the whole, and the relative size of each sector indicates its percent
of the whole. Since the whole is 100%, the sum of the percentages of all the sectors is 100 (plus or
minus a bit to account for rounding). Below is a pie chart created from the data used in the bar graph
and line graph shown earlier. In this example, labels indicating the exact percents are not supplied, but it
is still possible to gauge the size of the sectors relative to one another: the smallest percent of sales was
on ursday, and the largest was on Tuesday. In addition, the two radii that mark the boundaries of the
Tuesday sector form an obtuse angle, which indicates that the sector is greater than one‐fourth of the
circle. us, Tuesday’s sales comprised more than 25% of total sales.
Week 1 Sales by Day
Monday
Tuesday
Wednesday
ursday
Friday
A ow chart is a diagram that shows the steps in a process. Often, the steps are represented by symbols,
which are connected by arrows showing the ow of the process. Flow charts generally progress from
top to bottom or from left to right. In the simple ow chart below, rectangles indicate steps to be
completed. e diamond shape indicates a decision point: if the consultant is new, the process continues
to the next step, Append tax forms . If the consultant is not new, that step is bypassed and the contract is
mailed.
An organization chart represents the structure of an organization. Often, hierarchical relationships are
shown with vertical lines and lateral relationships are shown with horizontal lines. In the organization
chart at the top of the next page, each rectangle represents an employee or group of employees at a
small restaurant. All the employees in the second row of rectangles report to the restaurant manager. In
the third row, the food preparation sta and cleaning sta both report to the kitchen manager, and the
serving sta report to the serving sta manager.
Prepare
contract for
consultant
New
consultant?
No
Yes
Append
tax forms
Mail
contract
10.2 Integrated Reasoning The Question Types
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For all kinds of Graphics Interpretation questions, be sure to read the question carefully to be sure you
understand what is being asked. en read the statement or statements to determine what information
you need to learn from the graphic. Finally, choose the answer from each drop‐down menu that best
completes the statement or statements.
You will have 30 minutes to complete the Integrated Reasoning section, or an average of 2 minutes and
30 seconds to answer each question. Keep in mind, however, that each Graphics Interpretation question
has two blanks to be lled. Both blanks must be lled using the drop‐down menus in the time allowed.
Two-Part Analysis
Two‐Part Analysis questions present a brief written scenario or problem and ask you to make two
choices related to that information. ese choices are connected to each other in some way; for example,
they might be two steps involved in solving a problem or two components required to successfully
complete a task. In Two‐Part Analysis questions you may be asked to, for example,
• calculate the proportions of two di erent components in a mixture
• determine something that would be lost and something that would be gained in a trade‐o
• nd the maximum number of two di erent products that could be purchased within a certain
budget
• identify a rst action and a second action that together would bring a company into compliance
with a new rule
e possible answers and your choices will be given in a table format. e possible answers are listed
in the third column, on the right side of the table. Your choices for the rst part and second part of
the question will be recorded in the rst and second columns of the table, respectively. Remember that
you need to make a choice for each of the rst two vertical columns of the table—not one for each
horizontal row.
In answering Two‐Part Analysis questions, read the scenario or problem carefully. Be sure you
understand what the question is asking. Read all the answer options to be sure that your choices are the
best of those available, and be careful to mark your choices in the proper columns.
You will have 30 minutes to complete the Integrated Reasoning section, or an average of 2 minutes
and 30 seconds to answer each question. Keep in mind that you must make the two choices for each
Two‐Part Analysis question within that average amount of time.
chef kitchen
manager
serving sta
manager
cleaning
sta
food preparation
sta
serving
sta
restaurant
manager
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10.3 Test-Taking Strategies
Multi-Source Reasoning Questions
1. Do not expect to be completely familiar with the material presented in Multi‐Source
Reasoning sets.
You may nd some graphs, charts, tables, or verbal passages easier to understand than others. All
of the material is designed to be challenging, but if you have familiarity with the subject matter, do
not let this knowledge in uence your answer choices. Answer all questions on the basis of what is
given by the various sources of information.
2. Analyze each source of information carefully, because the questions require a detailed
understanding of the information presented.
Text passages often build ideas sequentially, so note as you read how each statement adds to the
main idea of the passage as a whole. Some of the passages used with Multi‐Source Reasoning
items will be purely descriptive while others may contain strong opinions.
Given that the graphic elements of Multi‐Source Reasoning items come in various forms—such
as tables, graphs, diagrams, or charts—brie y familiarize yourself with the information presented.
If scales are provided, note the marked values and labels. Also note the major graphical elements of
the information presented.
3. Read the questions carefully, making sure you understand what is being asked.
Some of the questions will require you to recognize discrepancies among di erent sources of
information, others will ask you to draw inferences using information from di erent sources, while
others may require you to determine which one of the information sources is relevant. You can
refer back to any of the sources at any time while you are answering the Multi‐Source Reasoning
questions.
4. Select the answer choices that have the most support based on the information provided.
You may nd it helpful to brie y familiarize yourself with the overall information given in the
sources and then to focus more closely on the speci c information needed to answer the question.
Table Analysis Questions
1. Examine the table and accompanying text to determine the type of information provided.
Orienting yourself to the data at the outset will make it easier to locate the information necessary
for completing the question.
2. Read the question carefully.
e question will contain the condition that each phrase, statement, numerical value, or algebraic
expression does or does not meet (for example, is or is not consistent with the information provided ,
or can or cannot be inferred from the information provided ). Clearly understanding the condition will
help you to clarify the choice to be made in each case.
10.3 Integrated Reasoning Test-Taking Strategies
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3. Read each phrase, statement, numerical value, or algebraic expression carefully to determine the
data analysis required.
Often, the phrase, statement, numerical value, or algebraic expression indicates a relationship that
can be clari ed by sorting the table on one or more of its columns. Careful reading can help you
work more e ciently by using table sorts strategically to identify data of interest.
4. Judge each phrase, statement, numerical value, or algebraic expression carefully on the basis of
the condition speci ed.
For each phrase, statement, numerical value, or algebraic expression, the two answer choices (such
as yes or no, true or false, consistent or inconsistent ) are mutually exclusive. us, you can focus your
attention on whether or not the given condition has been met.
Graphics Interpretation Questions
1. Read the graphic carefully.
Quickly familiarize yourself with the information presented in the graphic. If scales are provided
(such as on the axes) make note of the marked values. If there are labels, be sure to note any
discrepancy between the units in the graph and the units discussed in the text.
2. Read any accompanying text carefully .
If there is accompanying text, it may clarify the meaning of the graphic. Text might also present
information that is not contained in the graphic but that is necessary for answering the question.
3. Scan the choices in the drop‐down menu before you do any work .
Some statements could be completed equally well with very general responses as with very speci c
responses. Checking the menu options gives you additional information about the task involved.
4. Choose the option that best completes the statement .
More than one option in a drop‐down menu may seem plausible to you; in each menu, choose
the one that makes the statement most accurate or logical. If the drop‐down menu is preceded
by a phrase such as “nearest to” or the “closest to,” choose the option that is closest to the exact
answer you compute. You may nd that reading the entire statement again with your answer
choice in place is a helpful way to check your work.
Two-Part Analysis Questions
1. Read the information given carefully .
All of the material presented is designed to be challenging, but if you have familiarity with the
subject matter, do not let this knowledge in uence your answer choices. Answer each question only
on the basis of what is given.
2. Determine exactly what the question is asking .
Do not assume that the headings in the two response columns are complete descriptions of the
tasks to be performed. Pay close attention to how the question describes the tasks. Often the
headings in the two response columns are shorthand references to the tasks and may lack some
details that could help you to better understand what you are supposed to do.
3. Remember that only two choices are to be made .
Select one answer in each of the rst two columns of the response table. You do not need to
make a choice for each row of the table. e third column contains possible answers for the
two choices to be made.
799
4. Do not choose an answer before reviewing all of the available answer choices .
Do not assume that you have chosen the best answers in the two columns without reading all of
the available options.
5. Determine whether tasks are dependent or independent .
Some Two‐Part Analysis questions pose two independent tasks that can be carried out individually,
and others pose one task with two dependent parts, each of which must be carried out correctly to
create a single correct response. With questions of the dependent type, the question asked cannot
be answered coherently without making both choices, so be sure to examine your answers in
relation to one another.
6. Keep in mind that one answer choice can be the correct response for both columns .
If the tasks associated with the two response columns are not mutually exclusive, it is possible that
one answer choice satis es the conditions associated with both response columns.
10.4 The Directions
ese directions are similar to the directions given for the four question types in the Integrated
Reasoning section of the GMAT
® exam. Understanding them clearly before taking the test will save
you time during the test.
• Multi‐Source Reasoning . Click on the tabs and examine all the relevant information from text,
charts, and tables to answer the questions.
• Table Analysis . Analyze the table, sorting on columns as needed, to determine whether each of
the options presented meets the given criterion or not.
• Graphics Interpretation . Interpret the graph or graphical image and select from each drop‐down
menu the option that creates the most accurate statement based on the information provided.
• Two‐Part Analysis . Read the information provided, review the options presented in the table, and
indicate which option meets the criterion presented in the rst column and which option meets
the criterion presented in the second column. Make only two selections, one in each column.
For the Integrated Reasoning section, an onscreen calculator is available. To access the calculator, click
“Calculator” on the blue bar at the upper left of the screen. Note that the calculator can be dragged to
any part of the screen.
You can view explanations of the format of the speci c Integrated Reasoning questions anytime while
working through this section by clicking on HELP.
10.4 Integrated Reasoning The Directions
800
11.0 Analytical Writing Assessment
801
11.0 Analytical Writing Assessment
11.0 Analytical Writing Assessment
e Analytical Writing Assessment (AWA) consists of one 30‐minute writing task called the Analysis
of an Argument. In this section, you must read a brief argument, analyze the reasoning behind it, and
then write a critique of the argument. You are not asked to state your opinion but rather to analyze
the one given. For example, you may, consider what questionable assumptions underlie the author’s
thinking, what alternative explanations or counterexamples might weaken the conclusion, or what sort
of evidence could help strengthen or refute the argument.
For this task, you will use the computer keyboard to type your response. You will be able to use typical
word‐processing functions—that is, you can cut, copy, paste, undo, and redo. ese functions can be
accessed either by using the keyboard or by using the mouse to click on icons on the screen. You will be
able to take notes when planning your response.
It is important that you plan carefully before you begin writing. Read the speci c analytical writing
task several times to make sure you understand exactly what is expected. ink about how you might
present your analysis. You may want to sketch an outline to help you plan and organize. Keep in mind
the 30‐minute time limit as you plan your response—keep your analysis brief enough to allow for plenty
of time to write a rst draft, read it over carefully, and make any necessary corrections or revisions before
you run out of time. As you write, try to keep your language clear, your sentences concise, and the ow
of your ideas logical. State your premise clearly at the beginning, and make sure you present a strong
conclusion at the end.
11.1 What Is Measured
e Analytical Writing Assessment is designed as a direct measure of your ability to think critically
and communicate your ideas. More speci cally, the Analysis of an Argument task tests your ability to
formulate an appropriate and constructive critique of a prescribed conclusion based upon a speci c line
of thinking.
e argument that you will analyze may concern a topic of general interest, possibly related to business,
or to a variety of other subjects. It is important to note, however, that no Analysis of an Argument
question presupposes any speci c knowledge of business or other speci c content areas. Only your
capacity to write analytically is assessed.
Professional essay raters, including college and university faculty members from various subject‐matter
areas, including but not limited to management education, will evaluate your essay. For information on
how readers are quali ed, visit mba.com. Readers are trained to be sensitive and fair in evaluating the
responses of nonnative speakers of English. A computer scoring program will also evaluate your essays.
Your responses will be scored on the basis of:
• the overall quality of your ideas
• your ability to organize, develop, and express those ideas
• how well you provide relevant supporting reasons and examples
• your ability to control the elements of standard written English
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11.2 Test-Taking Strategies
1. Read the question carefully.
Make sure you have taken all parts of a question into account before you begin to respond to it.
2. Do not start to write immediately .
Take a few minutes to think about the question and plan a response before you begin writing. You
may nd it helpful to write a brief outline or jot down some ideas on the erasable notepad provided.
Take care to organize your ideas and develop them fully, but leave time to reread your response and
make any revisions that you think would improve it.
3. Focus on the task of analyzing and critiquing a line of thinking or reasoning .
Get used to asking yourself questions such as the following: What questionable assumptions might
underlie the thinking? What alternative explanations might be given? What counterexamples might be
raised? What additional evidence might prove useful in fully and fairly evaluating the reasoning?
4. Develop fully any examples you use .
Do not simply list your examples—explain how they illustrate your point.
5. Discuss alternative explanations or counterexamples .
ese techniques allow you to introduce illustrations and examples drawn from your observations,
experiences, and reading.
6. Make sure your response reads like a narrative .
Your response should not read like an outline. It should use full sentences, a coherent organizational
scheme, logical transitions between points, and appropriately introduced and developed examples.
11.3 The Directions
ese are the directions that you will see for the Analysis of an Argument essay. If you read them
carefully and understand them clearly before going to sit for the test, you will not need to spend too
much time reviewing them when you take the GMAT
® exam. ey read as follows:
ANALYSIS OF AN ARGUMENT
In this section, you will be asked to write a critique of the argument presented. You are not asked to
present your own views on the subject .
Writing Your Response: Take a few minutes to evaluate the argument and plan a response before you
begin writing. Be sure to leave enough time to reread your response and make any revisions that you
think are necessary.
Evaluation of Your Response: Scores will re ect how well you:
• organize, develop, and express your ideas about the argument presented
• provide relevant supporting reasons and examples
• control the elements of standard written English
803
11.4 GMAT
® Scoring Guide: Analysis of an Argument
6 Outstanding
A 6 paper presents a cogent, well‐articulated critique of the argument and demonstrates mastery of the
elements of e ective writing.
A typical paper in this category exhibits the following characteristics:
• clearly identi es important features of the argument and analyzes them insightfully
• develops ideas cogently, organizes them logically, and connects them with clear transitions
• e ectively supports the main points of the critique
• demonstrates control of language, including diction and syntactic variety
• demonstrates facility with the conventions of standard written English but may have minor aws
5 Strong
A 5 paper presents a well‐developed critique of the argument and demonstrates good control of the
elements of e ective writing.
A typical paper in this category exhibits the following characteristics:
• clearly identi es important features of the argument and analyzes them in a generally thoughtful
way
• develops ideas clearly, organizes them logically, and connects them with appropriate transitions
• sensibly supports the main points of the critique
• demonstrates control of language, including diction and syntactic variety
• demonstrates facility with the conventions of standard written English but may have occasional
aws
4 Adequate
A 4 paper presents a competent critique of the argument and demonstrates adequate control of the
elements of writing.
A typical paper in this category exhibits the following characteristics:
• identi es and analyzes important features of the argument
• develops and organizes ideas satisfactorily but may not connect them with transitions
• supports the main points of the critique
• demonstrates su cient control of language to convey ideas with reasonable clarity
• generally follows the conventions of standard written English but may have some aws
11.4 Analytical Writing Assessment GMAT® Scoring Guide: Analysis of an Argument
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3 Limited
A 3 paper demonstrates some competence in analytical writing skills and in its control of the elements
of writing but is plainly awed.
A typical paper in this category exhibits one or more of the following characteristics:
• does not identify or analyze most of the important features of the argument, although some analy-
sis of the argument is present
• mainly analyzes tangential or irrelevant matters, or reasons poorly
• is limited in the logical development and organization of ideas
• o ers support of little relevance and value for points of the critique
• does not convey meaning clearly
• contains occasional major errors or frequent minor errors in grammar, usage, and mechanics
2 Seriously Flawed
A 2 paper demonstrates serious weaknesses in analytical writing skills.
A typical paper in this category exhibits one or more of the following characteristics:
• does not present a critique based on logical analysis, but may instead present the writer’s own
views on the subject
• does not develop ideas, or is disorganized and illogical
• provides little, if any, relevant or reasonable support
• has serious and frequent problems in the use of language and in sentence structure
• contains numerous errors in grammar, usage, and mechanics that interfere with meaning
1 Fundamentally Defi cient
A 1 paper demonstrates fundamental de ciencies in analytical writing skills.
A typical paper in this category exhibits more than one of the following characteristics:
• provides little evidence of the ability to understand and analyze the argument
• provides little evidence of the ability to develop an organized response
• has severe and persistent errors in language and sentence structure
• contains a pervasive pattern of errors in grammar, usage, and mechanics that results in incoherence
0 No Score
A paper in this category is o topic, not written in English, is merely attempting to copy the topic, or
consists only of keystroke characters.
NR Blank
805
11.5 Sample: Analysis of an Argument
Read the statement and the instructions that follow it, and then make any notes that will help you
plan your response.
e following appeared as part of an article in a daily newspaper:
“ e computerized on‐board warning system that will be installed in commercial airliners will virtually
solve the problem of midair plane collisions. One plane’s warning system can receive signals from
another’s transponder—a radio set that signals a plane’s course—in order to determine the likelihood of
a collision and recommend evasive action.”
Discuss how well reasoned you nd this argument. In your discussion, be sure to analyze the line
of reasoning and the use of evidence in the argument. For example, you may need to consider what
questionable assumptions underlie the thinking and what alternative explanations or counterexamples
might weaken the conclusion. You can also discuss what sort of evidence would strengthen or refute the
argument, what changes in the argument would make it more logically sound, and what, if anything,
would help you better evaluate its conclusion.
Sample Paper 6
e argument that this warning system will virtually solve the problem of midair plane collisions
omits some important concerns that must be addressed to substantiate the argument. e statement
that follows the description of what this warning system will do simply describes the system and how
it operates. is alone does not constitute a logical argument in favor of the warning system, and it
certainly does not provide support or proof of the main argument.
Most conspicuously, the argument does not address the cause of the problem of midair plane collisions,
the use of the system by pilots and ight specialists, or who is involved in the midair plane collisions.
First, the argument assumes that the cause of the problem is that the planes’ courses, the likelihood
of collisions, and actions to avoid collisions are unknown or inaccurate. In a weak attempt to support
its claim, the argument describes a system that makes all of these things accurately known. But if the
cause of the problem of midair plane collisions is that pilots are not paying attention to their computer
systems or ight operations, the warning system will not solve the collision problem. Second, the
argument never addresses the interface between individuals and the system and how this will a ect
the warning system’s objective of obliterating the problem of collisions. If the pilot or ight specialist
does not conform to what the warning system suggests, midair collisions will not be avoided. Finally,
if planes other than commercial airliners are involved in the collisions, the problem of these collisions
cannot be solved by a warning system that will not be installed on non‐commercial airliners. e
argument also does not address what would happen in the event that the warning system collapses, fails,
or does not work properly.
Because the argument leaves out several key issues, it is not sound or persuasive. If it included the items
discussed above instead of solely explaining what the system supposedly does, the argument would have
been more thorough and convincing.
11.5 Analytical Writing Assessment Sample: Analysis of an Argument
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Explanation of Score 6
is response is, as the scoring guide requires of a 6, “cogent”and “well articulated”: all the points
made not only bear directly on the argument to be analyzed, but also contribute to a single, integrated
development of the writer’s critique. e writer begins by making the controlling point that a mere
description of the warning system’s mode of operation cannot serve as a true argument proving
the system’s e ectiveness, since the description overlooks several major considerations. e writer
then identi es these considerations—what causes midair collisions, how pilots will actually use the
commercial airline warning system, what kinds of airplanes are typically involved in midair collisions—
and, citing appropriate counterexamples (e.g., what if pilots do not pay attention to their instruments?),
explains fully how each oversight undermines the conclusion that the warning system will virtually
eliminate midair plane collisions.
roughout, the writer complements the logically organized development of this critique with good,
clear prose that demonstrates the ability not only to control language and vary sentence structure but
also to express ideas forcibly (e.g., “the argument never addresses the interface between individuals and
the system”). Of course, as in any response written under time constraints, occasional minor aws can
be found. For example, “the argument assumes that the cause of the problem is that the planes’ courses,
the likelihood of collisions, and actions to avoid collisions are unknown or inaccurate” is wordy and
imprecise: how can a course, a likelihood, or actions be inaccurate? But aws such as these, minor and
infrequent, do not interfere with the overall clarity and forcefulness of this outstanding response.
807
Sample Paper 4
e argument is not logically convincing. It does not state whether all planes can receive signals from
each other. It does not state whether planes constantly receive signals. If they only receive signals once
every certain time interval, collisions will not de nitely be prevented. Further if they receive a signal
right before they are about to crash, they cannot avoid each other.
e main aw in the argument is that it assumes that the two planes, upon receiving each other’s
signals, will know which evasive action to take. For example, the two planes could be going towards each
other and then receive the signals. If one turns at an angle to the left and the other turns at an angle to
the right, the two planes will still crash. Even if they receive an updated signal, they will not have time
to avoid each other.
e following argument would be more sound and persuasive. e new warning system will solve the
problem of midair plane collisions. Each plane will receive constant, continual signals from each other.
If the two planes are headed in a direction where they will crash, the system will coordinate the signals,
and tell one plane to go one way, and the other plane to go another way. e new system will ensure that
the two planes will turn in di erent directions so they don’t crash by trying to prevent the original crash.
In addition, the two planes will be able to see themselves and the other on a computer screen, to aid in
the evasive action.
Explanation of Score 4
is response competently cites a number of de ciencies in the argument presented: the information
given about the nature of the signals sent and received and the evasive action recommended does not
warrant the conclusion that the onboard warning system “will virtually solve the problem of midair
plane collisions.” However, in discussing these insu ciencies in the argument, the response reveals an
unevenness in the quality of its reasoning. For example, while it is perfectly legitimate to point out that
the argument assumes too much and says too little about the evasive action that will be recommended
by the warning system, it is farfetched to suggest that the system might be so poorly designed as to
route two approaching airplanes to the same spot. Likewise, while it is fair to question the e ectiveness
of a warning signal about which the argument says so little, it is not reasonable to assume that the
system would be designed to space signals so far apart that they would prove useless. Rather than
invent implausibly bad versions of the warning system to prove that it might be ine ective, a stronger
response would analyze unexplored possibilities inherent in the information that is given—for example,
the possibility that pilots might not be able to respond quickly and e ectively to the radio signals the
argument says they will receive when the new system is installed. e “more sound and persuasive
argument” in the last paragraph, while an improvement on the original, continues to overlook this
possibility and also assumes that other types of aircraft without transponders will pose no problems.
e organization of ideas, while generally sound, is sometimes weakened by needless repetition of the
same points, as in sentences 4 and 5 of the last paragraph. e writing contains minor instances of
awkwardness (e.g., “Each plane will receive constant, continual signals from each other” in paragraph 3),
but is free of aws that make understanding di cult. However, though the writing is generally clean
and clear, the syntax does not show much variety. A few sentences begin with “if ” clauses, but almost all
the rest, even those that begin with a transitional phrase such as “for example” or “in addition,” conform
to a “subject, verb, complement” pattern. e rst paragraph, in which the second and third sentences
begin the same way (“It does not state”), is particularly repetitious.
11.5 Analytical Writing Assessment Sample: Analysis of an Argument
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GMAT® Offi cial Guide 2018
Sample Paper 2
is argument has no information about air collisions. I think most cases happen in new airports
because the air tra c I heavy. In this case sound airport control could solve the problem.
I think this argument is logically reasonable. Its assumption is that plane collisions are caused by planes
that don’t know each others positions. So pilots can do nothing, if they know each others position
through the system it will solve the problem.
If it can provide evidence the problem is lack of knowledge of each others positions, it will be more
sound and persuasive.
More information about air collisions is helpful, (the reason for air collisions).
Explanation of Score 2
is response is seriously awed in several ways. First of all, it has very little substance. e writer
appears to make only one point—that while it seems reasonable to assume that midair collisions
would be less likely if pilots were sure of each other’s positions, readers cannot adequately judge this
assumption without more information about where, why, and how such collisions occur. is point,
furthermore, is neither explained by a single reason beyond what is given in the topic nor supported by a
single example. Legitimate though it is, it cannot, alone and undeveloped, serve as an adequate response
to the argument.
Aside from being undeveloped, the response is confusing. At the outset, it seems to be critical of the
argument. e writer begins by pointing to the inadequacy of the information given; then speculates,
without evidence, that “most cases happen in new airports”; and then suggests that the problem should
be addressed by improving “airport control,” not (it is implied) by installing onboard warning systems.
After criticizing the argument in the rst paragraph, the writer confusingly seems to endorse it in the
second. en, in the remainder of the response, the writer returns to a critical stance.
e general lack of coherence is re ected in the serious and frequent writing problems that make
meaning hard to determine—for example, the elliptical and ungrammatical “So pilots can do nothing,
if they know each others position through the system it will solve the problem” (paragraph 2) or “If it
can provide evidence the problem is lack of knowledge of each others positions, it will be more sound
and persuasive” (paragraph 3). e prose su ers from a variety of basic errors in grammar, usage, and
mechanics.
809
11.6 Analysis of an Argument Sample Topics
The following appeared as part of an annual report sent to stockholders by Olympic Foods, a processor of frozen
foods:
“Over time, the costs of processing go down because as organizations learn how to do things better, they become
more ef cient. In color lm processing, for example, the cost of a 3‐by‐5‐inch print fell from 50 cents for ve‐day
service in 1970 to 20 cents for one‐day service in 1984. The same principle applies to the processing of food.
And since Olympic Foods will soon celebrate its 25th birthday, we can expect that our long experience will enable
us to minimize costs and thus maximize pro ts.”
Discuss how well reasoned you nd this argument. In your discussion be sure to analyze the line of reasoning
and the use of evidence in the argument. For example, you may need to consider what questionable assumptions
underlie the thinking and what alternative explanations or counterexamples might weaken the conclusion. You can
also discuss what sort of evidence would strengthen or refute the argument, what changes in the argument would
make it more logically sound, and what, if anything, would help you better evaluate its conclusion.
____________________________
The following appeared in a memorandum from the business department of the Apogee Company:
“When the Apogee Company had all its operations in one location, it was more pro table than it is today. Therefore,
the Apogee Company should close down its eld of ces and conduct all its operations from a single location. Such
centralization would improve pro tability by cutting costs and helping the company maintain better supervision of
all employees.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum issued by a large city’s council on the arts:
“In a recent citywide poll, 15 percent more residents said that they watch television programs about the visual arts
than was the case in a poll conducted ve years ago. During these past ve years, the number of people visiting
our city’s art museums has increased by a similar percentage. Since the corporate funding that supports public
television, where most of the visual arts programs appear, is now being threatened with severe cuts, we can expect
that attendance at our city’s art museums will also start to decrease. Thus some of the city’s funds for supporting
the arts should be reallocated to public television.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a report presented for discussion at a meeting of the directors of a company that
manufactures parts for heavy machinery:
“The falling revenues that the company is experiencing coincide with delays in manufacturing. These delays,
in turn, are due in large part to poor planning in purchasing metals. Consider further that the manager of
the department that handles purchasing of raw materials has an excellent background in general business,
psychology, and sociology, but knows little about the properties of metals. The company should, therefore, move
the purchasing manager to the sales department and bring in a scientist from the research division to be manager
of the purchasing department.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
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GMAT® Offi cial Guide 2018
The following appeared in an announcement issued by the publisher of The Mercury , a weekly newspaper:
“Since a competing lower‐priced newspaper, The Bugle , was started ve years ago, The Mercury ’s circulation has
declined by 10,000 readers. The best way to get more people to read The Mercury is to reduce its price below
that of The Bugle , at least until circulation increases to former levels. The increased circulation of The Mercury will
attract more businesses to buy advertising space in the paper.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in a magazine devoted to regional life:
“Corporations should look to the city of Helios when seeking new business opportunities or a new location. Even
in the recent recession, Helios’s unemployment rate was lower than the regional average. It is the industrial
center of the region, and historically it has provided more than its share of the region’s manufacturing jobs. In
addition, Helios is attempting to expand its economic base by attracting companies that focus on research and
development of innovative technologies.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the health section of a magazine on trends and lifestyles:
“People who use the arti cial sweetener aspartame are better off consuming sugar, since aspartame can actually
contribute to weight gain rather than weight loss. For example, high levels of aspartame have been shown to
trigger a craving for food by depleting the brain of a chemical that registers satiety, or the sense of being full.
Furthermore, studies suggest that sugars, if consumed after at least 45 minutes of continuous exercise, actually
enhance the body’s ability to burn fat. Consequently, those who drink aspartame‐sweetened juices after exercise
will also lose this calorie‐burning bene t. Thus it appears that people consuming aspartame rather than sugar are
unlikely to achieve their dietary goals.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the editorial section of a corporate newsletter:
“The common notion that workers are generally apathetic about management issues is false, or at least outdated:
a recently published survey indicates that 79 percent of the nearly 1,200 workers who responded to survey
questionnaires expressed a high level of interest in the topics of corporate restructuring and redesign of bene ts
programs.”
Discuss how well reasoned … etc.
811
The following appeared in the opinion column of a nancial magazine:
“On average, middle‐aged consumers devote 39 percent of their retail expenditure to department store products
and services, while for younger consumers the average is only 25 percent. Since the number of middle‐aged
people will increase dramatically within the next decade, department stores can expect retail sales to increase
signi cantly during that period. Furthermore, to take advantage of the trend, these stores should begin to replace
some of those products intended to attract the younger consumer with products intended to attract the middle‐
aged consumer.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the editorial section of a local newspaper:
“This past winter, 200 students from Waymarsh State College traveled to the state capitol building to protest
against proposed cuts in funding for various state college programs. The other 12,000 Waymarsh students
evidently weren’t so concerned about their education: they either stayed on campus or left for winter break. Since
the group who did not protest is far more numerous, it is more representative of the state’s college students than
are the protesters. Therefore the state legislature need not heed the appeals of the protesting students.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the editorial section of a local newspaper:
“In the rst four years that Montoya has served as mayor of the city of San Perdito, the population has decreased
and the unemployment rate has increased. Two businesses have closed for each new business that has opened.
Under Varro, who served as mayor for four years before Montoya, the unemployment rate decreased and the
population increased. Clearly, the residents of San Perdito would be best served if they voted Montoya out of of ce
and reelected Varro.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of a promotional campaign to sell advertising space in the Daily Gazette to grocery
stores in the Marston area:
“Advertising the reduced price of selected grocery items in the Daily Gazette will help you increase your sales.
Consider the results of a study conducted last month. Thirty sale items from a store in downtown Marston
were advertised in The Gazette for four days. Each time one or more of the 30 items was purchased, clerks
asked whether the shopper had read the ad. Two‐thirds of the 200 shoppers asked answered in the af rmative.
Furthermore, more than half the customers who answered in the af rmative spent over $100 at the store.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
812
GMAT® Offi cial Guide 2018
The following appeared as part of a campaign to sell advertising time on a local radio station to local businesses:
“The Cumquat Café began advertising on our local radio station this year and was delighted to see its business
increase by 10 percent over last year’s totals. Their success shows you how you can use radio advertising to
make your business more pro table.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of a newspaper editorial:
“Two years ago Nova High School began to use interactive computer instruction in three academic subjects. The
school dropout rate declined immediately, and last year’s graduates have reported some impressive achievements
in college. In future budgets the school board should use a greater portion of the available funds to buy more
computers, and all schools in the district should adopt interactive computer instruction throughout the curriculum.”
Discuss how well reasoned … etc.
____________________________
The following appeared as a part of an advertisement for Adams, who is seeking re‐election as governor:
“Re‐elect Adams, and you will be voting for proven leadership in improving the state’s economy. Over the past year
alone, 70 percent of the state’s workers have had increases in their wages, 5,000 new jobs have been created,
and six corporations have located their headquarters here. Most of the respondents in a recent poll said they
believed that the economy is likely to continue to improve if Adams is re‐elected. Adams’s opponent, Zebulon,
would lead our state in the wrong direction, because Zebulon disagrees with many of Adams’s economic policies.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in the education section of a Waymarsh city newspaper:
“Throughout the last two decades, those who earned graduate degrees found it very dif cult to get jobs teaching
their academic specialties at the college level. Those with graduate degrees from Waymarsh University had
an especially hard time nding such jobs. But better times are coming in the next decade for all academic job
seekers, including those from Waymarsh. Demographic trends indicate that an increasing number of people will
be reaching college age over the next 10 years; consequently, we can expect that the job market will improve
dramatically for people seeking college‐level teaching positions in their elds.”
Discuss how well reasoned … etc.
813
The following appeared in an article in a consumer‐products magazine:
“Two of today’s best‐selling brands of full‐strength prescription medication for the relief of excess stomach acid,
Acid‐Ease and Pepticaid, are now available in milder nonprescription forms. Doctors have written 76 million more
prescriptions for full‐strength Acid‐Ease than for full‐strength Pepticaid. So people who need an effective but milder
nonprescription medication for the relief of excess stomach acid should choose Acid‐Ease.”
Discuss how well reasoned … etc.
____________________________
The following is an excerpt from a memo written by the head of a governmental department:
“Neither stronger ethics regulations nor stronger enforcement mechanisms are necessary to ensure ethical
behavior by companies doing business with this department. We already have a code of ethics that companies
doing business with this department are urged to abide by, and virtually all of these companies have agreed to
follow it. We also know that the code is relevant to the current business environment because it was approved
within the last year, and in direct response to speci c violations committed by companies with which we were then
working—not in abstract anticipation of potential violations, as so many such codes are.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in the travel section of a newspaper:
“Over the past decade, the restaurant industry in the country of Spiessa has experienced unprecedented growth.
This surge can be expected to continue in the coming years, fueled by recent social changes: personal incomes
are rising, more leisure time is available, single‐person households are more common, and people have a greater
interest in gourmet food, as evidenced by a proliferation of publications on the subject.”
Discuss how well reasoned … etc.
____________________________
The following appeared in an article in a health and tness magazine:
“Laboratory studies show that Saluda Natural Spring Water contains several of the minerals necessary for good
health and that it is completely free of bacteria. Residents of Saluda, the small town where the water is bottled,
are hospitalized less frequently than the national average. Even though Saluda Natural Spring Water may seem
expensive, drinking it instead of tap water is a wise investment in good health.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
814
GMAT® Offi cial Guide 2018
The following appeared as part of an editorial in an industry newsletter:
“While trucking companies that deliver goods pay only a portion of highway maintenance costs and no property
tax on the highways they use, railways spend billions per year maintaining and upgrading their facilities. The
government should lower the railroad companies’ property taxes, since sending goods by rail is clearly a more
appropriate mode of ground transportation than highway shipping. For one thing, trains consume only a third of the
fuel a truck would use to carry the same load, making them a more cost‐effective and environmentally sound mode
of transport. Furthermore, since rail lines already exist, increases in rail traf c would not require building new lines
at the expense of taxpaying citizens.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the editorial section of a newspaper:
“As public concern over drug abuse has increased, authorities have become more vigilant in their efforts to
prevent illegal drugs from entering the country. Many drug traf ckers have consequently switched from marijuana,
which is bulky, or heroin, which has a market too small to justify the risk of severe punishment, to cocaine. Thus
enforcement efforts have ironically resulted in an observed increase in the illegal use of cocaine.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a speech delivered by a member of the city council:
“Twenty years ago, only half of the students who graduated from Einstein High School went on to attend a college
or university. Today, two‐thirds of the students who graduate from Einstein do so. Clearly, Einstein has improved
its educational effectiveness over the past two decades. This improvement has occurred despite the fact that the
school’s funding, when adjusted for in ation, is about the same as it was 20 years ago. Therefore, we do not need
to make any substantial increase in the school’s funding at this time.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memo from the customer service division to the manager of Mammon Savings and
Loan:
“We believe that improved customer service is the best way for us to differentiate ourselves from competitors and
attract new customers. We can offer our customers better service by reducing waiting time in teller lines from an
average of six minutes to an average of three. By opening for business at 8:30 instead of 9:00, and by remaining
open for an additional hour beyond our current closing time, we will be better able to accommodate the busy
schedules of our customers. These changes will enhance our bank’s image as the most customer‐friendly bank in
town and give us the edge over our competition.”
Discuss how well reasoned … etc.
815
The following appeared as part of an article in a magazine on lifestyles:
“Two years ago, City L was listed fourteenth in an annual survey that ranks cities according to the quality of life
that can be enjoyed by those living in them. This information will enable people who are moving to the state in
which City L is located to con dently identify one place, at least, where schools are good, housing is affordable,
people are friendly, the environment is safe, and the arts ourish.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from a member of a nancial management and consulting rm:
“We have learned from an employee of Windfall, Ltd., that its accounting department, by checking about 10
percent of the last month’s purchasing invoices for errors and inconsistencies, saved the company some $10,000
in overpayments. In order to help our clients increase their net gains, we should advise each of them to institute a
policy of checking all purchasing invoices for errors. Such a recommendation could also help us get the Windfall
account by demonstrating to Windfall the rigorousness of our methods.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a newspaper editorial:
“As violence in movies increases, so do crime rates in our cities. To combat this problem we must establish a
board to censor certain movies, or we must limit admission to persons over 21 years of age. Apparently our
legislators are not concerned about this issue since a bill calling for such actions recently failed to receive a
majority vote.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the editorial section of a local newspaper:
“Commuter use of the new subway train is exceeding the transit company’s projections. However, commuter
use of the shuttle buses that transport people to the subway stations is below the projected volume. If the transit
company expects commuters to ride the shuttle buses to the subway rather than drive there, it must either reduce
the shuttle bus fares or increase the price of parking at the subway stations.”
Discuss how well reasoned … etc.
____________________________
The following was excerpted from the speech of a spokesperson for Synthetic Farm Products, Inc.:
“Many farmers who invested in the equipment needed to make the switch from synthetic to organic fertilizers and
pesticides feel that it would be too expensive to resume synthetic farming at this point. But studies of farmers who
switched to organic farming last year indicate that their current crop yields are lower. Hence their purchase of organic
farming equipment, a relatively minor investment compared to the losses that would result from continued lower crop
yields, cannot justify persisting on an unwise course. And the choice to farm organically is nancially unwise, given that it
was motivated by environmental rather than economic concerns.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
816
GMAT® Offi cial Guide 2018
The following appeared in a newspaper story giving advice about investments:
“As overall life expectancy continues to rise, the population of our country is growing increasingly older. For
example, more than 20 percent of the residents of one of our more populated regions are now at least 65 years
old, and occupancy rates at resort hotels in that region declined signi cantly during the past six months. Because
of these two related trends, a prudent investor would be well advised to sell interest in hotels and invest in
hospitals and nursing homes instead.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of the business plan of an investment and nancial consulting rm:
“Studies suggest that an average coffee drinker’s consumption of coffee increases with age, from age 10 through
age 60. Even after age 60, coffee consumption remains high. The average cola drinker’s consumption of cola,
however, declines with increasing age. Both of these trends have remained stable for the past 40 years. Given that
the number of older adults will signi cantly increase as the population ages over the next 20 years, it follows that
the demand for coffee will increase and the demand for cola will decrease during this period. We should, therefore,
consider transferring our investments from Cola Loca to Early Bird Coffee.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the editorial section of a West Cambria newspaper:
“A recent review of the West Cambria volunteer ambulance service revealed a longer average response time to
accidents than was reported by a commercial ambulance squad located in East Cambria. In order to provide better
patient care for accident victims and to raise revenue for our town by collecting service fees for ambulance use,
we should disband our volunteer service and hire a commercial ambulance service.”
Discuss how well reasoned … etc.
____________________________
The following is part of a business plan being discussed at a board meeting of the Perks Company:
“It is no longer cost‐effective for the Perks Company to continue offering its employees a generous package of
bene ts and incentives year after year. In periods when national unemployment rates are low, Perks may need to
offer such a package in order to attract and keep good employees, but since national unemployment rates are
now high, Perks does not need to offer the same bene ts and incentives. The money thus saved could be better
used to replace the existing plant machinery with more technologically sophisticated equipment, or even to build
an additional plant.”
Discuss how well reasoned … etc.
817
The following appeared as part of a plan proposed by an executive of the Easy Credit Company to the president:
“The Easy Credit Company would gain an advantage over competing credit card services if we were to donate a
portion of the proceeds from the use of our cards to a well‐known environmental organization in exchange for the
use of its symbol or logo on our card. Since a recent poll shows that a large percentage of the public is concerned
about environmental issues, this policy would attract new customers, increase use among existing customers, and
enable us to charge interest rates that are higher than the lowest ones available.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of a recommendation from the nancial planning of ce to the administration of Fern
Valley University:
“In the past few years, Fern Valley University has suffered from a decline in both enrollments and admissions
applications. The reason can be discovered from our students, who most often cite poor teaching and inadequate
library resources as their chief sources of dissatisfaction with Fern Valley. Therefore, in order to increase the
number of students attending our university, and hence to regain our position as the most prestigious university in
the greater Fern Valley metropolitan area, it is necessary to initiate a fund‐raising campaign among the alumni that
will enable us to expand the range of subjects we teach and to increase the size of our library facilities.”
Discuss how well reasoned … etc.
____________________________
The following appeared in an article in a college departmental newsletter:
“Professor Taylor of Jones University is promoting a model of foreign language instruction in which students
receive 10 weeks of intensive training, then go abroad to live with families for 10 weeks. The superiority of the
model, Professor Taylor contends, is proved by the results of a study in which foreign language tests given to
students at 25 other colleges show that rst‐year foreign language students at Jones speak more uently after
only 10 to 20 weeks in the program than do 9 out of 10 foreign language majors elsewhere at the time of their
graduation.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in the business section of a local newspaper:
“Motorcycle X has been manufactured in the United States for more than 70 years. Although one foreign company
has copied the motorcycle and is selling it for less, the company has failed to attract motorcycle X customers—
some say because its product lacks the exceptionally loud noise made by motorcycle X. But there must be some
other explanation. After all, foreign cars tend to be quieter than similar American‐made cars, but they sell at least
as well. Also, television advertisements for motorcycle X highlight its durability and sleek lines, not its noisiness,
and the ads typically have voice‐overs or rock music rather than engine‐roar on the sound track.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
818
GMAT® Offi cial Guide 2018
The following appeared in the editorial section of a campus newspaper:
“Because occupancy rates for campus housing fell during the last academic year, so did housing revenues.
To solve the problem, campus housing of cials should reduce the number of available housing units, thereby
increasing the occupancy rates. Also, to keep students from choosing to live off‐campus, housing of cials should
lower the rents, thereby increasing demand.”
Discuss how well reasoned … etc.
____________________________
The following appeared in an Avia Airlines departmental memorandum:
“On average, 9 out of every 1,000 passengers who traveled on Avia Airlines last year led a complaint about our
baggage‐handling procedures. This means that although some 1 percent of our passengers were unhappy with
those procedures, the overwhelming majority were quite satis ed with them; thus it would appear that a review of
the procedures is not important to our goal of maintaining or increasing the number of Avia’s passengers.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in a weekly newsmagazine:
“The country of Sacchar can best solve its current trade de cit problem by lowering the price of sugar, its primary
export. Such an action would make Sacchar better able to compete for markets with other sugar‐exporting
countries. The sale of Sacchar’s sugar abroad would increase, and this increase would substantially reduce
Sacchar’s trade de cit.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in a trade publication:
“Stronger laws are needed to protect new kinds of home‐security systems from being copied and sold by imitators.
With such protection, manufacturers will naturally invest in the development of new home‐security products and
production technologies. Without stronger laws, therefore, manufacturers will cut back on investment. From this will
follow a corresponding decline not only in product quality and marketability, but also in production ef ciency, and thus
ultimately a loss of manufacturing jobs in the industry.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the opinion section of a national newsmagazine:
“To reverse the deterioration of the postal service, the government should raise the price of postage stamps. This
solution will no doubt prove effective, since the price increase will generate larger revenues and will also reduce
the volume of mail, thereby eliminating the strain on the existing system and contributing to improved morale.”
Discuss how well reasoned … etc.
819
The following appeared in an article in the health section of a newspaper:
“There is a common misconception that university hospitals are better than community or private hospitals. This
notion is unfounded, however: the university hospitals in our region employ 15 percent fewer doctors, have a 20
percent lower success rate in treating patients, make far less overall pro t, and pay their medical staff considerably
less than do private hospitals. Furthermore, many doctors at university hospitals typically divide their time among
teaching, conducting research, and treating patients. From this it seems clear that the quality of care at university
hospitals is lower than that at other kinds of hospitals.”
Discuss how well reasoned … etc.
____________________________
The following is part of a business plan created by the management of the Megamart grocery store:
“Our total sales have increased this year by 20 percent since we added a pharmacy section to our grocery
store. Clearly, the customer’s main concern is the convenience afforded by one‐stop shopping. The surest way
to increase our pro ts over the next couple of years, therefore, is to add a clothing department along with an
automotive supplies and repair shop. We should also plan to continue adding new departments and services, such
as a restaurant and a garden shop, in subsequent years. Being the only store in the area that offers such a range
of services will give us a competitive advantage over other local stores.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of a column in a popular entertainment magazine:
“The producers of the forthcoming movie 3003 will be most likely to maximize their pro ts if they are willing to
pay Robin Good several million dollars to star in it—even though that amount is far more than any other person
involved with the movie will make. After all, Robin has in the past been paid a similar amount to work in several
lms that were very nancially successful.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from the directors of a security and safety consulting service:
“Our research indicates that over the past six years no incidents of employee theft have been reported within ten
of the companies that have been our clients. In analyzing the security practices of these ten companies, we have
further learned that each of them requires its employees to wear photo identi cation badges while at work. In the
future, therefore, we should recommend the use of such identi cation badges to all of our clients.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in the business section of a local newspaper:
“The owners of the Cumquat Cafe evidently made a good business decision in moving to a new location, as can be seen
from the fact that the Cafe will soon celebrate its second anniversary there. Moreover, it appears that businesses are
not likely to succeed at the old location: since the Cafe’s move, three different businesses—a tanning salon, an antique
emporium, and a pet‐grooming shop—have occupied its former spot.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
820
GMAT® Offi cial Guide 2018
The following appeared in the editorial section of a local newspaper:
“The pro tability of Croesus Company, recently restored to private ownership, is a clear indication that businesses
fare better under private ownership than under public ownership.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the editorial section of a local newspaper:
“If the paper from every morning edition of the nation’s largest newspaper were collected and rendered into paper
pulp that the newspaper could reuse, about 5 million trees would be saved each year. This kind of recycling is
unnecessary, however, since the newspaper maintains its own forests to ensure an uninterrupted supply of paper.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of a business plan recommended by the new manager of a musical rock group
called Zapped:
“To succeed nancially, Zapped needs greater name recognition. It should therefore diversify its commercial
enterprises. The rock group Zonked plays the same type of music that Zapped plays, but it is much better known
than Zapped because, in addition to its concert tours and four albums, Zonked has a series of posters, a line
of clothing and accessories, and a contract with a major advertising agency to endorse a number of different
products.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a magazine article on trends and lifestyles:
“In general, people are not as concerned as they were a decade ago about regulating their intake of red meat and
fatty cheeses. Walk into the Heart’s Delight, a store that started selling organic fruits and vegetables and whole‐
grain ours in the 1960s, and you will also nd a wide selection of cheeses made with high butterfat content. Next
door, the owners of the Good Earth Cafe, an old vegetarian restaurant, are still making a modest living, but the
owners of the new House of Beef across the street are millionaires.”
Discuss how well reasoned … etc.
____________________________
The following editorial appeared in the Elm City paper:
“The construction last year of a shopping mall in downtown Oak City was a mistake. Since the mall has opened,
a number of local businesses have closed, and the downtown area suffers from an acute parking shortage, and
arrests for crime and vagrancy have increased in the nearby Oak City Park. Elm City should pay attention to the
example of the Oak City mall and deny the application to build a shopping mall in Elm City.”
Discuss how well reasoned … etc.
821
The following appeared as part of an editorial in a weekly newsmagazine:
“Historically, most of this country’s engineers have come from our universities; recently, however, our university‐
age population has begun to shrink, and decreasing enrollments in our high schools clearly show that this drop
in numbers will continue throughout the remainder of the decade. Consequently, our nation will soon be facing a
shortage of trained engineers. If we are to remain economically competitive in the world marketplace, then we
must increase funding for education—and quickly.”
Discuss how well reasoned … etc.
____________________________
The following appeared in an Excelsior Company memorandum:
“The Excelsior Company plans to introduce its own brand of coffee. Since coffee is an expensive food item, and
since there are already many established brands of coffee, the best way to gain customers for the Excelsior brand
is to do what Superior, the leading coffee company, did when it introduced the newest brand in its line of coffees:
conduct a temporary sales promotion that offers free samples, price reductions, and discount coupons for the new
brand.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in a health club trade publication:
“After experiencing a decline in usage by its members, Healthy Heart tness center built an indoor pool. Since
usage did not increase signi cantly, it appears that health club managers should adopt another approach—
lowering membership fees rather than installing expensive new features.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in a popular arts‐and‐leisure magazine:
“The safety codes governing the construction of public buildings are becoming far too strict. The surest way for
architects and builders to prove that they have met the minimum requirements established by these codes is to
construct buildings by using the same materials and methods that are currently allowed. But doing so means
that there will be very little signi cant technological innovation within the industry, and hence little evolution of
architectural styles and design—merely because of the strictness of these safety codes.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
822
GMAT® Offi cial Guide 2018
The following is from a campaign by Big Boards Inc. to convince companies in River City that their sales will
increase if they use Big Boards billboards for advertising their locally manufactured products:
“The potential of Big Boards to increase sales of your products can be seen from an experiment we conducted
last year. We increased public awareness of the name of the current national women’s marathon champion by
publishing her picture and her name on billboards in River City for a period of three months. Before this time,
although the champion had just won her title and was receiving extensive national publicity, only 5 percent of
15,000 randomly surveyed residents of River City could correctly name the champion when shown her picture;
after the three‐month advertising experiment, 35 percent of respondents from a second survey could supply her
name.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article on government funding of environmental regulatory agencies:
“When scientists nally learn how to create large amounts of copper from other chemical elements, the regulation
of copper mining will become unnecessary. For one thing, since the amount of potentially available copper will no
longer be limited by the quantity of actual copper deposits, the problem of over‐mining will quickly be eliminated
altogether. For another, manufacturers will not need to use synthetic copper substitutes, the production of which
creates pollutants. Thus, since two problems will be settled—over‐mining and pollution—it makes good sense to
reduce funding for mining regulation and either save the money or reallocate it where it is needed more.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in a popular science magazine:
“Scientists must typically work 60 to 80 hours a week if they hope to further their careers; consequently, good
and affordable all‐day child care must be made available to both male and female scientists if they are to advance
in their elds. Moreover, requirements for career advancement must be made more exible so that preschool‐age
children can spend a signi cant portion of each day with a parent.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of a recommendation by one of the directors of the Beta Company:
“The Alpha Company has just reduced its workforce by laying off 15 percent of its employees in all divisions
and at all levels, and it is encouraging early retirement for other employees. As you know, the Beta Company
manufactures some products similar to Alpha’s, but our pro ts have fallen over the last few years. To improve
Beta’s competitive position, we should try to hire a signi cant number of Alpha’s former workers, since these
experienced workers can provide valuable information about Alpha’s successful methods, will require little training,
and will be particularly motivated to compete against Alpha.”
Discuss how well reasoned … etc.
823
The following appeared in the letters‐to‐the‐editor section of a local newspaper:
“ Muscle Monthly , a tness magazine that regularly features pictures of bodybuilders using state‐of‐the‐art exercise
machines, frequently sells out, according to the owner of Skyview Newsstand. To help maximize tness levels in our town’s
residents, we should, therefore, equip our new community tness center with such machines.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in the business section of a local newspaper:
“The Cumquat Cafe made a mistake in moving to a new location. After one year at the new spot, it is doing about
the same volume of business as before, but the owners of the RoboWrench plumbing supply wholesale outlet that
took over its old location are apparently doing better: RoboWrench is planning to open a store in a neighboring
city.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from the director of human resources to the executive of cers of
Company X:
“Last year, we surveyed our employees on improvements needed at Company X by having them rank, in order
of importance, the issues presented in a list of possible improvements. Improved communications between
employees and management was consistently ranked as the issue of highest importance by the employees who
responded to the survey. As you know, we have since instituted regular communications sessions conducted by
high‐level management, which the employees can attend on a voluntary basis. Therefore, it is likely that most
employees at Company X now feel that the improvement most needed at the company has been made.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from the vice president of Road Food, an international chain of fast‐food
restaurants:
“This past year, we spent almost as much on advertising as did our main competitor, Street Eats, which has fewer
restaurants than we do. Although it appeared at rst that our advertising agency had created a campaign along
the lines we suggested, in fact our total pro ts were lower than those of Street Eats. In order to motivate our
advertising agency to perform better, we should start basing the amount that we pay it on how much total pro t
we make each year.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the promotional literature for Cerberus dog food:
“Obesity is a great problem among pet dogs, just as it is among their human owners. Obesity in humans is
typically caused by consuming more calories than the body needs. For humans, a proper diet for losing weight is
a reduced‐calorie diet that is high in ber and carbohydrates but low in fat. Therefore, the best way for dog owners
to help their dogs lose weight in a healthy way is to restrict the dog’s diet to Cerberus reduced‐calorie dog food,
which is high in ber and carbohydrates but low in fat.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
824
GMAT® Offi cial Guide 2018
The following appeared in an article in a travel magazine:
“After the airline industry began requiring airlines to report their on‐time rates, Speedee Airlines achieved the
number one on‐time rate, with more than 89 percent of its ights arriving on time each month. And now Speedee
is offering more ights to more destinations than ever before. Clearly, Speedee is the best choice for today’s
business traveler.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum to the planning department of an investment rm:
“Costs have begun dropping for several types of equipment currently used to convert solar energy into electricity.
Moreover, some exciting new technologies for converting solar energy are now being researched and developed.
Hence we can expect that solar energy will soon become more cost ef cient and attractive than coal or oil
as a source of electrical power. We should, therefore, encourage investment in Solario, a new manufacturer
of solar‐powered products. After all, Solario’s chief executive was once on the nancial planning team for
Ready‐to‐Ware, a software engineering rm that has shown remarkable growth since its recent incorporation.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from a company’s marketing department:
“Since our company started manufacturing and marketing a deluxe air lter six months ago, sales of our economy
lter—and company pro ts—have decreased signi cantly. The deluxe air lter sells for 50 percent more than
the economy lter, but the economy lter lasts for only one month while the deluxe lter can be used for two
months before it must be replaced. To increase repeat sales of our economy lter and maximize pro ts, we should
discontinue the deluxe air lter and concentrate all our advertising efforts on the economy lter.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from the president of a company that makes shampoo:
“A widely publicized study claims that HR2, a chemical compound in our shampoo, can contribute to hair loss after
prolonged use. This study, however, involved only 500 subjects. Furthermore, we have received no complaints
from our customers during the past year, and some of our competitors actually use more HR2 per bottle of
shampoo than we do. Therefore, we do not need to consider replacing the HR2 in our shampoo with a more
expensive alternative.”
Discuss how well reasoned … etc.
825
The following appeared in the editorial section of a local newspaper:
“The tragic crash of a medical helicopter last week points out a situation that needs to be addressed. The medical‐
helicopter industry supposedly has more stringent guidelines for training pilots and maintaining equipment than do
most other airline industries, but these guidelines do not appear to be working: statistics reveal that the rate of
medical‐helicopter accidents is much higher than the rate of accidents for nonmedical helicopters or commercial
airliners.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of a recommendation from the business manager of a department store:
“Local clothing stores reported that their pro ts decreased, on average, for the three‐month period between
August 1 and October 31. Stores that sell products for the home reported that, on average, their pro ts increased
during this same period. Clearly, consumers are choosing to buy products for their homes instead of clothing.
To take advantage of this trend, we should reduce the size of our clothing departments and enlarge our home
furnishings and household products departments.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a letter to the editor of a regional newspaper:
“In response to petitions from the many farmers and rural landowners throughout our region, the legislature has
spent valuable time and effort enacting severe laws to deter motorists from picking fruit off the trees, trampling
through the elds, and stealing samples of foliage. But how can our local lawmakers occupy themselves with such
petty vandalism when crime and violence plague the nation’s cities? The fate of apples and leaves is simply too
trivial to merit their attention.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an editorial in a campus newspaper:
“With an increasing demand for highly skilled workers, this nation will soon face a serious labor shortage. New
positions in technical and professional occupations are increasing rapidly, while at the same time the total labor
force is growing slowly. Moreover, the government is proposing to cut funds for aid to education in the near
future.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of a memorandum from a government agency:
“Given the limited funding available for the building and repair of roads and bridges, the government should not
spend any money this year on xing the bridge that crosses the Styx River. This bridge is located near a city with
a weakening economy, so it is not as important as other bridges; moreover, the city population is small and thus
unlikely to contribute a signi cant enough tax revenue to justify the effort of xing the bridge.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
826
GMAT® Offi cial Guide 2018
The following appeared as part of an article in an entertainment magazine:
“A series of books based on the characters from a popular movie are consistently best sellers in local bookstores.
Seeking to capitalize on the books’ success, Vista Studios is planning to produce a movie sequel based on the
books. Due to the success of the books and the original movie, the sequel will undoubtedly be pro table.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a letter to the editor of a popular science and technology magazine:
“It is a popular myth that consumers are really bene ting from advances in agricultural technology. Granted,
consumers are, on the average, spending a decreasing proportion of their income on food. But consider that the
demand for food does not rise in proportion with real income. As real income rises, therefore, consumers can be
expected to spend a decreasing proportion of their income on food. Yet agricultural technology is credited with
having made our lives better.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the editorial section of a local newspaper:
“This city should be able to improve existing services and provide new ones without periodically raising the taxes
of the residents. Instead, the city should require that the costs of services be paid for by developers who seek
approval for their large new building projects. After all, these projects can be highly pro table to the developers,
but they can also raise a city’s expenses and increase the demand for its services.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the editorial section of a local newspaper:
“In order to avoid the serious health threats associated with many land lls, our municipality should build a plant for
burning trash. An incinerator could offer economic as well as ecological advantages over the typical old‐fashioned
type of land ll: incinerators can be adapted to generate moderate amounts of electricity, and ash residue from
some types of trash can be used to condition garden soil.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the editorial section of a monthly business newsmagazine:
“Most companies would agree that as the risk of physical injury occurring on the job increases, the wages paid to
employees should also increase. Hence it makes nancial sense for employers to make the workplace safer: they
could thus reduce their payroll expenses and save money.”
Discuss how well reasoned … etc.
827
The following appeared as part of a company memorandum:
“Adopting an of cial code of ethics regarding business practices may in the long run do our company more harm
than good in the public eye. When one of our competitors received unfavorable publicity for violating its own code
of ethics, it got more attention from the media than it would have if it had had no such code. Rather than adopt an
of cial code of ethics, therefore, we should instead conduct a publicity campaign that stresses the importance of
protecting the environment and assisting charitable organizations.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the editorial section of a daily newspaper:
“Although forecasts of presidential elections based on opinion polls measure current voter preference, many voters
keep changing their minds about whom they prefer until the last few days before the balloting. Some do not even
make a nal decision until they enter the voting booth. Forecasts based on opinion polls are therefore little better
at predicting election outcomes than a random guess would be.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the editorial section of a newspaper in the country of West Cambria:
“The practice of of cially changing speed limits on the highways—whether by increasing or decreasing them—is
a dangerous one. Consider what happened over the past decade whenever neighboring East Cambria changed its
speed limits: an average of 3 percent more automobile accidents occurred during the week following the change
than had occurred during the week preceding it—even when the speed limit was lowered. This statistic shows that
the change in speed limit adversely affected the alertness of drivers.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of a memorandum from the vice president of Nostrum, a large pharmaceutical
corporation:
“The proposal to increase the health and retirement bene ts that our employees receive should not be
implemented at this time. An increase in these bene ts is not only nancially unjusti ed, since our last year’s pro ts
were lower than those of the preceding year, but also unnecessary, since our chief competitor, Panacea, offers its
employees lower health and retirement bene ts than we currently offer. We can assume that our employees are
reasonably satis ed with the health and retirement bene ts that they now have since a recent survey indicated that
two‐thirds of the respondents viewed them favorably.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
828
GMAT® Offi cial Guide 2018
The following appeared as part of an article on trends in television:
“A recent study of viewers’ attitudes toward prime‐time television programs shows that many of the programs
that were judged by their viewers to be of high quality appeared on (noncommercial) television networks, and
that, on commercial television, the most popular shows are typically sponsored by the bestselling products. Thus,
it follows that businesses who use commercial television to promote their products will achieve the greatest
advertising success by sponsoring only highly rated programs—and, ideally, programs resembling the highly rated
noncommercial programs on public channels as much as possible.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in the business section of a daily newspaper:
“Company A has a large share of the international market in video‐game hardware and software. Company B, the
pioneer in these products, was once a $12 billion‐a‐year giant but collapsed when children became bored with its
line of products. Thus Company A can also be expected to fail, especially given the fact that its games are now in
so many American homes that the demand for them is nearly exhausted.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in a photography magazine:
“When choosing whether to work in color or in black‐and‐white, the photographer who wishes to be successful
should keep in mind that because color photographs are more true to life, magazines use more color photographs
than black‐and‐white ones, and many newspapers are also starting to use color photographs. The realism of color
also accounts for the fact that most portrait studios use more color lm than black‐and‐white lm. Furthermore,
there are more types of color lm than black‐and‐white lm available today. Clearly, photographers who work in
color have an advantage over those who work in black‐and‐white.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of a letter to the editor of a local newspaper:
“It makes no sense that in most places 15‐year‐olds are not eligible for their driver’s license while people who are
far older can retain all of their driving privileges by simply renewing their license. If older drivers can get these
renewals, often without having to pass another driving test, then 15‐year‐olds should be eligible to get a license.
Fifteen‐year‐olds typically have much better eyesight, especially at night; much better hand‐eye coordination; and
much quicker re exes. They are also less likely to feel confused by unexpected developments or disoriented in
unfamiliar surroundings, and they recover from injuries more quickly.”
Discuss how well reasoned … etc.
829
The following appeared in an ad for a book titled How to Write a Screenplay for a Movie :
“Writers who want to succeed should try to write lm screenplays rather than books, since the average lm tends
to make greater pro ts than does even a best‐selling book. It is true that some books are also made into lms.
However, our nation’s lm producers are more likely to produce movies based on original screenplays than to
produce lms based on books, because in recent years the lms that have sold the most tickets have usually been
based on original screenplays.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in a daily newspaper:
“The computerized onboard warning system that will be installed in commercial airliners will virtually solve the
problem of midair plane collisions. One plane’s warning system can receive signals from another’s transponder—a
radio set that signals a plane’s course—in order to determine the likelihood of a collision and recommend evasive
action.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from the ElectroWares company’s marketing department:
“Since our company started manufacturing and marketing a deluxe light bulb six months ago, sales of our
economy light bulb—and company pro ts—have decreased signi cantly. Although the deluxe light bulb sells for
50 percent more than the economy bulb, it lasts twice as long. Therefore, to increase repeat sales and maximize
pro ts, we should discontinue the deluxe light bulb.”
Discuss how well reasoned … etc.
____________________________
The following is taken from an editorial in a local newspaper:
“Over the past decade, the price per pound of citrus fruit has increased substantially. Eleven years ago, Megamart
charged 15 cents a pound for lemons, but today it commonly charges over a dollar a pound. In only one of these
last 11 years was the weather unfavorable for growing citrus crops. Evidently, then, citrus growers have been
responsible for the excessive increase in the price of citrus fruit, and strict pricing regulations are needed to
prevent them from continuing to in ate prices.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in a local newspaper:
“Over the past three years the tart sh industry has changed markedly: shing technology has improved
signi cantly, and the demand for tart sh has grown in both domestic and foreign markets. As this trend continues,
the tart sh industry on Shrimp Island can expect to experience the same over shing problems that are already
occurring with mainland shing industries: without restrictions on shing, shers see no reason to limit their
individual catches. As the catches get bigger, the tart sh population will be dangerously depleted while the surplus
of tart sh will devalue the catch for shers. Government regulation is the only answer: tart sh‐ shing should be
allowed only during the three‐month summer season, when tart sh reproduce and thus are most numerous, rather
than throughout the year.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
830
GMAT® Offi cial Guide 2018
The following appeared in a proposal from the development of ce at Platonic University:
“Because Platonic University has had dif culty in meeting its expenses over the past three years, we need to nd new
ways to increase revenues. We should consider following the example of Greene University, which recently renamed
itself after a donor who gave it $100 million. If Platonic University were to advertise to its alumni and other wealthy
people that it will rename either individual buildings or the entire university itself after the donors who give the most
money, the amount of donations would undoubtedly increase.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in the business section of a local newspaper:
“Hippocrene Plumbing Supply recently opened a wholesale outlet in the location once occupied by the Cumquat
Café. Hippocrene has apparently been quite successful there because it is planning to open a large outlet in a
nearby city. But the Cumquat Café, one year after moving to its new location, has seen its volume of business drop
somewhat from the previous year’s. Clearly, the former site was the better business location, and the Cumquat
Café has made a mistake in moving to its new address.”
Discuss how well reasoned … etc.
____________________________
The following appeared in the editorial section of a local paper:
“Applications for advertising spots on KMTV, our local cable television channel, decreased last year. Meanwhile
a neighboring town’s local channel, KOOP, changed its focus to farming issues and reported an increase in
advertising applications for the year. To increase applications for its advertisement spots, KMTV should focus its
programming on farming issues as well.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in a computer magazine:
“A year ago Apex Manufacturing bought its managers computers for their homes and paid for telephone
connections so that they could access Apex computers and data les from home after normal business hours.
Since last year, productivity at Apex has increased by 15 percent. Other companies can learn from the success
at Apex: given home computers and access to company resources, employees will work additional hours at home
and thereby increase company pro ts.”
Discuss how well reasoned … etc.
____________________________
The following was excerpted from an article in a farming trade publication:
“Farmers who switched from synthetic to organic farming last year have seen their crop yields decline. Many of
these farmers feel that it would be too expensive to resume synthetic farming at this point, given the money that
they invested in organic farming supplies and equipment. But their investments will be relatively minor compared
to the losses from continued lower crop yields. Organic farmers should switch to synthetic farming rather than
persist in an unwise course. And the choice to farm organically is nancially unwise, given that it was motivated by
environmental rather than economic concerns.”
Discuss how well reasoned … etc.
831
The following appeared in a letter to prospective students from the admissions of ce at Plateau College:
“Every person who earned an advanced degree in science or engineering from Olympus University last year
received numerous offers of excellent jobs. Typically, many graduates of Plateau College have gone on to pursue
advanced degrees at Olympus. Therefore, enrolling as an undergraduate at Plateau College is a wise choice for
students who wish to ensure success in their careers.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum sent by a vice‐president of the Nadir Company to the company’s human
resources department:
“Nadir does not need to adopt the costly ‘family‐friendly’ programs that have been proposed, such as part‐time
work, work at home, and jobsharing. When these programs were made available at the Summit Company, the
leader in its industry, only a small percentage of employees participated in them. Rather than adversely affecting
our pro tability by offering these programs, we should concentrate on offering extensive training that will enable
employees to increase their productivity.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in a trade magazine for breweries:
“Magic Hat Brewery recently released the results of a survey of visitors to its tasting room last year. Magic Hat
reports that the majority of visitors asked to taste its low‐calorie beers. To boost sales, other small breweries
should brew low‐calorie beers as well.”
Discuss how well reasoned … etc.
____________________________
The following appeared in an editorial from a newspaper serving the town of Saluda:
“The Saluda Consolidated High School offers more than 200 different courses from which its students can
choose. A much smaller private school down the street offers a basic curriculum of only 80 different courses,
but it consistently sends a higher proportion of its graduating seniors on to college than Consolidated does. By
eliminating at least half of the courses offered there and focusing on a basic curriculum, we could improve student
performance at Consolidated and also save many tax dollars.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
832
GMAT® Offi cial Guide 2018
The following appeared as part of an article in the book section of a newspaper:
“Currently more and more books are becoming available in electronic form—either free‐of‐charge on the Internet
or for a very low price‐per‐book on compact disc. Thus literary classics are likely to be read more widely than
ever before. People who couldn’t have purchased these works at bookstore prices will now be able to read them
for little or no money; similarly, people who nd it inconvenient to visit libraries and wait for books to be returned
by other patrons will now have access to whatever classic they choose from their home or work computers.
This increase in access to literary classics will radically affect the public taste in reading, creating a far more
sophisticated and learned reading audience than has ever existed before.”
Discuss how well reasoned … etc.
____________________________
The following appeared as an editorial in a magazine concerned with educational issues:
“In our country, the real earnings of men who have only a high‐school degree have decreased signi cantly over
the past 15 years, but those of male college graduates have remained about the same. Therefore, the key to
improving the earnings of the next generation of workers is to send all students to college. Our country’s most
important educational goal, then, should be to establish enough colleges and universities to accommodate all high
school graduates.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of a business plan created by the management of the Take Heart Fitness Center:
“After opening the new swimming pool early last summer, Take Heart saw a 12 percent increase in the use of
the center by its members. Therefore, in order to increase membership in Take Heart, we should continue to add
new recreational facilities in subsequent years: for example, a multipurpose game room, a tennis court, and a
miniature golf course. Being the only center in the area offering this range of activities would give us a competitive
advantage in the health and recreation market.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a letter from a staff member in the of ce of admissions at Argent University:
“The most recent nationwide surveys show that undergraduates choose their major eld primarily based on their
perception of job prospects in that eld. At our university, economics is now the most popular major, so students
must perceive this eld as having the best job prospects. Therefore, we can increase our enrollment if we focus
our advertising and recruiting on publicizing the accomplishments of our best‐known economics professors and
the success of our economics graduates in nding employment.”
Discuss how well reasoned … etc.
833
The following appeared as part of a memorandum from the loan department of the Frostbite National Bank:
“We should not approve the business loan application of the local group that wants to open a franchise outlet for
the Kool Kone chain of ice cream parlors. Frostbite is known for its cold winters, and cold weather can mean slow
ice cream sales. For example, even though Frostbite is a town of 10,000 people, it has only one ice cream spot—
the Frigid Cow. Despite the lack of competition, the Frigid Cow’s net revenues fell by 10 percent last winter.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of a letter to the editor of a local newspaper:
“Bayview High School is considering whether to require all of its students to wear uniforms while at school.
Students attending Acorn Valley Academy, a private school in town, earn higher grades on average and are more
likely to go on to college. Moreover, Acorn Valley reports few instances of tardiness, absenteeism, or discipline
problems. Since Acorn Valley requires its students to wear uniforms, Bayview High School would do well to follow
suit and require its students to wear uniforms as well.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memo to the Saluda town council from the town’s business manager:
“Research indicates that those who exercise regularly are hospitalized less than half as often as those who don’t
exercise. By providing a well‐equipped gym for Saluda’s municipal employees, we should be able to reduce the
cost of our group health insurance coverage by approximately 50 percent and thereby achieve a balanced town
budget.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum written by the assistant manager of a store that sells gourmet food
items from various countries:
“A local wine store made an interesting discovery last month: it sold more French than Italian wine on days when it
played recordings of French accordion music, but it sold more Italian than French wine on days when Italian songs
were played. Therefore, I recommend that we put food specialties from one particular country on sale for a week
at a time and play only music from that country while the sale is going on. By this means we will increase our
pro ts in the same way that the wine store did, and we will be able to predict more precisely what items we should
stock at any given time.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
834
GMAT® Offi cial Guide 2018
The following appeared in a memorandum from the director of research and development at Ready‐to‐Ware, a
software engineering rm:
“The package of bene ts and incentives that Ready‐to‐Ware offers to professional staff is too costly. Our quarterly
pro ts have declined since the package was introduced two years ago, at the time of our incorporation. Moreover,
the package had little positive effect, as we have had only marginal success in recruiting and training high‐quality
professional staff. To become more pro table again, Ready‐to‐Ware should, therefore, offer the reduced bene ts
package that was in place two years ago and use the savings to fund our current research and development
initiatives.”
Discuss how well reasoned … etc.
____________________________
The following appeared as a memorandum from the vice‐president of the Dolci candy company:
“Given the success of our premium and most expensive line of chocolate candies in a recent taste test and the
consequent increase in sales, we should shift our business focus to producing additional lines of premium candy
rather than our lower‐priced, ordinary candies. When the current economic boom ends and consumers can no
longer buy major luxury items, such as cars, they will still want to indulge in small luxuries, such as expensive
candies.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from the business of ce of the Lovin’ Cupful, a national restaurant chain:
“The Lovin’ Cupful franchises in our northeast region have begun serving customers Almost, a brand new
powdered instant tea, in place of brewed tea. Waiters report that only about 2 percent of the customers have
complained, and that customers who want re lls typically ask for ‘more tea.’ It appears, then, that 98 percent of
the customers are perfectly happy with the switch, or else they cannot tell powdered instant from brewed tea.
Therefore, in order to take advantage of the lower price per pound of Almost, all of our restaurants should begin
substituting it for brewed tea.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from the director of marketing for a pharmaceutical company:
“According to a survey of 5,000 urban residents, the prevalence of stress headaches increases with educational
level, so that stress headaches occur most often among people with graduate‐school degrees. It is well
established that, nationally, higher educational levels usually correspond with higher levels of income. Therefore,
in marketing our new pain remedy, Omnilixir, we should send free samples primarily to graduate students and to
people with graduate degrees, and we should concentrate on advertising in professional journals rather than in
general interest magazines.”
Discuss how well reasoned … etc.
835
The following appeared as part of an editorial in the Waymarsh city newspaper:
“Last year the parents of rst graders in our school district expressed satisfaction with the reading skills their
children developed but complained strongly about their children’s math skills. To remedy this serious problem and
improve our district’s elementary education, everyone in the teacher‐training program at Waymarsh University
should be required to take more courses in mathematics.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a letter to the editor of a River City newspaper:
“The Clio Development Group should not be permitted to build a multilevel parking garage on Dock Street since
most of the buildings on the block would have to be demolished. Because these buildings were erected decades
ago, they have historic signi cance and must therefore be preserved as economic assets in the effort to revitalize
a restored riverfront area. Recall how Lakesburg has bene ted from business increases in its historic downtown
center. Moreover, there is plenty of vacant land for a parking lot elsewhere in River City.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a corporate planning memorandum for a company that develops amusement parks:
“Because travel from our country to foreign countries has increased dramatically in recent years, our next project
should be a ‘World Tour’ theme park with replicas of famous foreign buildings, rides that have international themes,
and refreshment stands serving only foods from the country represented by the nearest ride. The best location
would be near our capital city, which has large percentages of international residents and of children under the age
of 16. Given the advantages of this site and the growing interest in foreign countries, the ‘World Tour’ theme park
should be as successful as our space‐travel theme park, where attendance has increased tenfold over the past
decade.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from the publisher to the staff of The Clarion , a large metropolitan
newspaper:
“During the recent campaign for mayor, a clear majority of city readers who responded to our survey indicated
a desire for more news about city government. To increase circulation, and thus our pro ts, weshould therefore
consistently devote a greater proportion of space in all editions of The Clarion to coverage of local news.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
836
GMAT® Offi cial Guide 2018
The following appeared in a memorandum from the assistant manager of Pageturner Books:
“Over the past two years, Pageturner’s pro ts have decreased by 5 percent, even though we have added a popular
café as well as a music section selling CDs and tapes. At the same time, we have experienced an increase in the
theft of merchandise. We should therefore follow the example of Thoreau Books, which increased its pro ts after
putting copies of its most frequently stolen books on a high shelf behind the payment counter. By doing likewise
with copies of the titles that our staff reported stolen last year, we too can increase pro tability.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a letter to the editor of a River City newspaper:
“The Clio Development Group’s plan for a multilevel parking garage on Dock Street should be approved in order
to strengthen the economy of the surrounding area. Although most of the buildings on the block would have to be
demolished, they are among the oldest in the city and thus of little current economic value. Those who oppose the
project should realize that historic preservation cannot be the only consideration: even Athens or Jerusalem will
knock down old buildings to put up new ones that improve the local economy.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from the owner of Carlo’s Clothing to the staff:
“Since Disc Depot, the music store on the next block, began a new radio advertising campaign last year, its
business has grown dramatically, as evidenced by the large increase in foot traf c into the store. While the Disc
Depot’s owners have apparently become wealthy enough to retire, pro ts at Carlo’s Clothing have remained
stagnant for the past three years. In order to boost our sales and pro ts, we should therefore switch from
newspaper advertising to frequent radio advertisements like those for Disc Depot.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of the business plan of the Capital Idea investment rm:
“Across town in the Park Hill district, the Thespian Theater, Pizzazz Pizza, and the Niblick Golf Club have all had
business increases over the past two years. Capital Idea should therefore invest in the Roxy Playhouse, the
Slice‐o’‐Pizza, and the Divot Golf Club, three new businesses in the Irongate district. As a condition, we should
require them to participate in a special program: Any customer who patronizes two of the businesses will receive
a substantial discount at the third. By motivating customers to patronize all three, we will thus contribute to the
pro tability of each and maximize our return.”
Discuss how well reasoned … etc.
837
The following appeared as part of an article in a newsletter for farmers:
“Users of Solacium, a medicinal herb now grown mainly in Asia, report that it relieves tension and promotes
deep sleep. A recent study indicates that a large number of college students who took pills containing one of
the ingredients in Solacium suffered less anxiety. To satisfy the anticipated demands for this very promising
therapeutic herb and to reap the nancial bene ts, farmers in this country should begin growing it.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from the president of Aurora, a company that sells organic milk (milk
produced without the use of chemical additives):
“Sales of organic food products in this country have tripled over the past ve years. If Aurora is to pro t from this
continuing trend, we must diversify and start selling products such as organic orange juice and organic eggs in
addition to our regular product line. With the recent increase of articles in health magazines questioning the safety
of milk and other food products, customers are even more likely to buy our line of organic products. And to help
ensure our successful expansion, we should hire the founder of a chain of health‐food stores to serve as our vice
president of marketing.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from the human resources department of Diversi ed Manufacturing:
“Managers at our central of ce report that their employees tend to be most productive in the days immediately
preceding a vacation. To help counteract our declining market share, we could increase the productivity of our
professional staff members, who currently receive four weeks paid vacation a year, by limiting them to a maximum
of one week’s continuous vacation time. They will thus take more vacation breaks during a year and give us more
days of maximum productivity.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from a regional supervisor of post of ce operations:
“During a two‐week study of postal operations, the Presto City post of ce handled about twice as many items
as the Lento City post of ce, even though the cities are about the same size. Moreover, customer satisfaction
appears to be higher in Presto City, since the study found fewer complaints regarding the Presto City post of ce.
Therefore, the postmasters at these two of ces should exchange assignments: the Presto City postmaster
will solve the problems of inef ciency and customer dissatisfaction at the Lento City of ce while the Lento City
postmaster learns rsthand the superior methods of Presto City.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
838
GMAT® Offi cial Guide 2018
The following appeared in a memorandum written by the managing director of the Exeunt Theater Company:
“Now that we have moved to a larger theater, we can expect to increase our revenues from ticket sales. To further
increase pro ts, we should start producing the plays that have been most successful when they were performed
in our nation’s largest cities. In addition, we should hire the Adlib Theater Company’s director of fund‐raising, since
corporate contributions to Adlib have increased signi cantly over the three years that she has worked for Adlib.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from the human resources department of HomeStyle, a house
remodeling business:
“This year, despite HomeStyle’s move to new of ce space, we have seen a decline in both company morale and
productivity, and a corresponding increase in administrative costs. To rectify these problems, we should begin
using a newly developed software package for performance appraisal and feedback. Managers will save time by
simply choosing comments from a preexisting list; then the software will automatically generate feedback for the
employee. The human resources department at CounterBalance, the manufacturer of the countertops we install,
reports satisfaction with the package.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in a weekly newsmagazine:
“The country of Oleum can best solve the problem of its balance‐of‐trade de cit by further increasing the tax on
its major import, crude oil. After Oleum increased the tax on imported crude oil four months ago, consumption of
gasoline declined by 20 percent. Therefore, by imposing a second and signi cantly higher tax increase next year,
Oleum will dramatically decrease its balance-of-trade de cit.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of a business plan by the Capital Idea investment rm:
“In recent years the worldwide demand for sh has grown, and improvements in shing technology have made
larger catches, and thus increased supply, possible: for example, last year’s tuna catch was 9 percent greater than
the previous year’s. To capitalize on these trends, we should therefore invest in the new tart sh processing plant
on Tart sh Island, where increasing revenues from tourism indicate a strong local economy.”
Discuss how well reasoned … etc.
839
The following appeared in a speech by a stockholder of Consolidated Industries at the company’s annual
stockholders’ meeting:
“In the computer hardware division last year, pro ts fell signi cantly below projections, the product line decreased
from 20 to only 5 items, and expenditures for employee bene ts increased by 15 percent. Nevertheless,
Consolidated’s board of directors has approved an annual salary of more than $1 million for our company’s chief
executive of cer. The present board members should be replaced because they are unconcerned about the
increasing costs of employee bene ts and salaries, in spite of the company’s problems generating income.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum from the business planning department of Avia Airlines:
“Of all the cities in their region, Beaumont and Fletcher are showing the fastest growth in the number of new
businesses. Therefore, Avia should establish a commuter route between them as a means of countering recent
losses on its main passenger routes. And to make the commuter route more pro table from the outset, Avia
should offer a 1/3 discount on tickets purchased within two days of the ight. Unlike tickets bought earlier,
discount tickets will be nonrefundable, and so gain from their sale will be greater.”
Discuss how well reasoned … etc.
___________________________
The following appeared in a memorandum from the vice president of Gigantis, a development company that builds
and leases retail store facilities:
“Nationwide over the past ve years, sales have increased signi cantly at outlet stores that deal exclusively in
reduced‐price merchandise. Therefore, we should publicize the new mall that we are building at Pleasantville as
a central location for outlet shopping and rent store space only to outlet companies. By taking advantage of the
success of outlet stores, this plan should help ensure full occupancy of the mall and enable us to recover quickly
the costs of building the mall.”
Discuss how well reasoned … etc.
____________________________
The following appeared in a memorandum written by the chair of the music department to the president of Omega
University:
“Mental health experts have observed that symptoms of mental illness are less pronounced in many patients
after group music‐therapy sessions, and job openings in the music‐therapy eld have increased during the past
year. Consequently, graduates from our degree program for music therapists should have no trouble nding good
positions. To help improve the nancial status of Omega University, we should therefore expand our music‐therapy
degree program by increasing its enrollment targets.”
Discuss how well reasoned … etc.
11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics
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GMAT® Offi cial Guide 2018
The following appeared in a memorandum to the work‐group supervisors of the GBS Company:
“The CoffeeCart beverage and food service located in the lobby of our main of ce building is not earning enough
in sales to cover its costs, and so the cart may discontinue operating at GBS. Given the low staff morale, as
evidenced by the increase in the number of employees leaving the company, the loss of this service could present
a problem, especially since the staff morale questionnaire showed widespread dissatisfaction with the snack
machines. Therefore, supervisors should remind the employees in their group to patronize the cart—after all, it
was leased for their convenience so that they would not have to walk over to the cafeteria on breaks.”
Discuss how well reasoned … etc.
____________________________
The following appeared as part of an article in a trade magazine:
“During a recent trial period in which government inspections at selected meat‐processing plants were more
frequent, the amount of bacteria in samples of processed chicken decreased by 50 percent on average from the
previous year’s level. If the government were to institute more frequent inspections, the incidence of stomach and
intestinal infections throughout the country could thus be cut in half. In the meantime, consumers of Excel Meats
should be safe from infection because Excel’s main processing plant has shown more improvement in eliminating
bacterial contamination than any other plant cited in the government report.”
Discuss how well reasoned … etc.
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841
Diagnostic Answer
Sheet—Quantitative
1. 27.
2. 28.
3. 29.
4. 30.
5. 31.
6. 32.
7. 33.
8. 34.
9. 35.
10. 36.
11. 37.
12. 38.
13. 39.
14. 40.
15. 41.
16. 42.
17. 43.
18. 44.
19. 45.
20. 46.
21. 47.
22. 48.
23.
24.
25.
26.
Diagnostic Answer
Sheet—Verbal
49. 75.
50. 76.
51. 77.
52. 78.
53. 79.
54. 80.
55. 81.
56. 82.
57. 83.
58. 84.
59. 85.
60. 86.
61. 87.
62. 88.
63. 89.
64. 90.
65. 91.
66. 92.
67. 93.
68. 94.
69. 95.
70. 96.
71. 97.
72. 98.
73. 99.
74. 100.
Appendix A Answer Sheets
GMAT® Offi cial Guide 2018
842
Problem Solving Answer Sheet
1. 32. 63. 94. 125. 156. 187. 218.
2. 33. 64. 95. 126. 157. 188. 219.
3. 34. 65. 96. 127. 158. 189. 220.
4. 35. 66. 97. 128. 159. 190. 221.
5. 36. 67. 98. 129. 160. 191. 222.
6. 37. 68. 99. 130. 161. 192. 223.
7. 38. 69. 100. 131. 162. 193. 224.
8. 39. 70. 101. 132. 163. 194. 225.
9. 40. 71. 102. 133. 164. 195. 226.
10. 41. 72. 103. 134. 165. 196. 227.
11. 42. 73. 104. 135. 166. 197. 228.
12. 43. 74. 105. 136. 167. 198. 229.
13. 44. 75. 106. 137. 168. 199. 230.
14. 45. 76. 107. 138. 169. 200.
15. 46. 77. 108. 139. 170. 201.
16. 47. 78. 109. 140. 171. 202.
17. 48. 79. 110. 141. 172. 203.
18. 49. 80. 111. 142. 173. 204.
19. 50. 81. 112. 143. 174. 205.
20. 51. 82. 113. 144. 175. 206.
21. 52. 83. 114. 145. 176. 207.
22. 53. 84. 115. 146. 177. 208.
23. 54. 85. 116. 147. 178. 209.
24. 55. 86. 117. 148. 179. 210.
25. 56. 87. 118. 149. 180. 211.
26. 57. 88. 119. 150. 181. 212.
27. 58. 89. 120. 151. 182. 213.
28. 59. 90. 121. 152. 183. 214.
29. 60. 91. 122. 153. 184. 215.
30. 61. 92. 123. 154. 185. 216.
31. 62. 93. 124. 155. 186. 217.
843
Appendix A Answer Sheets
231. 266. 301. 336. 371.
232. 267. 302. 337. 372.
233. 268. 303. 338. 373.
234. 269. 304. 339. 374.
235. 270. 305. 340. 375.
236. 271. 306. 341. 376.
237. 272. 307. 342. 377.
238. 273. 308. 343. 378.
239. 274. 309. 344. 379.
240. 275. 310. 345. 380.
241. 276. 311. 346. 381.
242. 277. 312. 347. 382.
243. 278. 313. 348. 383.
244. 279. 314. 349. 384.
245. 280. 315. 350. 385.
246. 281. 316. 351. 386.
247. 282. 317. 352. 387.
248. 283. 318. 353. 388.
249. 284. 319. 354. 389.
250. 285. 320. 355. 390.
251. 286. 321. 356. 391.
252. 287. 322. 357. 392.
253. 288. 323. 358. 393.
254. 289. 324. 359. 394.
255. 290. 325. 360. 395.
256. 291. 326. 361. 396.
257. 292. 327. 362. 397.
258. 293. 328. 363. 398.
259. 294. 329. 364. 399.
260. 295. 330. 365. 400.
261. 296. 331. 366. 401.
262. 297. 332. 367. 402.
263. 298. 333. 368. 403.
264. 299. 334. 369. 404.
265. 300. 335. 370.
Data Suffi ciency Answer Sheet
GMAT® Offi cial Guide 2018
844
405. 433. 461. 489. 517.
406. 434. 462. 490. 518.
407. 435. 463. 491. 519.
408. 436. 464. 492. 520.
409. 437. 465. 493. 521.
410. 438. 466. 494. 522.
411. 439. 467. 495. 523.
412. 440. 468. 496. 524.
413. 441. 469. 497. 525.
414. 442. 470. 498. 526.
415. 443. 471. 499. 527.
416. 444. 472. 500. 528.
417. 445. 473. 501. 529.
418. 446. 474. 502. 530.
419. 447. 475. 503. 531.
420. 448. 476. 504. 532.
421. 449. 477. 505. 533.
422. 450. 478. 506. 534.
423. 451. 479. 507. 535.
424. 452. 480. 508. 536.
425. 453. 481. 509. 537.
426. 454. 482. 510. 538.
427. 455. 483. 511. 539.
428. 456. 484. 512. 540.
429. 457. 485. 513. 541.
430. 458. 486. 514. 542.
431. 459. 487. 515. 543.
432. 460. 488. 516.
Reading Comprehension Answer Sheet
845
Appendix A Answer Sheets
Critical Reasoning Answer Sheet
544. 569. 594. 619. 644.
545. 570. 595. 620. 645.
546. 571. 596. 621. 646.
547. 572. 597. 622. 647.
548. 573. 598. 623. 648.
549. 574. 599. 624. 649.
550. 575. 600. 625. 650.
551. 576. 601. 626. 651.
552. 577. 602. 627. 652.
553. 578. 603. 628. 653.
554. 579. 604. 629. 654.
555. 580. 605. 630. 655.
556. 581. 606. 631. 656.
557. 582. 607. 632. 657.
558. 583. 608. 633. 658.
559. 584. 609. 634. 659.
560. 585. 610. 635. 660.
561. 586. 611. 636. 661.
562. 587. 612. 637. 662.
563. 588. 613. 638. 663.
564. 589. 614. 639. 664.
565. 590. 615. 640. 665.
566. 591. 616. 641. 666.
567. 592. 617. 642. 667.
568. 593. 618. 643.
GMAT® Offi cial Guide 2018
846
Sentence Correction Answer Sheet
668. 696. 724. 752. 780.
669. 697. 725. 753. 781.
670. 698. 726. 754. 782.
671. 699. 727. 755. 783.
672. 700. 728. 756. 784.
673. 701. 729. 757. 785.
674. 702. 730. 758. 786.
675. 703. 731. 759. 787.
676. 704. 732. 760. 788.
677. 705. 733. 761. 789.
678. 706. 734. 762. 790.
679. 707. 735. 763. 791.
680. 708. 736. 764. 792.
681. 709. 737. 765. 793.
682. 710. 738. 766. 794.
683. 711. 739. 767. 795.
684. 712. 740. 768. 796.
685. 713. 741. 769. 797.
686. 714. 742. 770. 798.
687. 715. 743. 771. 799.
688. 716. 744. 772. 800.
689. 717. 745. 773. 801.
690. 718. 746. 774. 802.
691. 719. 747. 775. 803.
692. 720. 748. 776. 804.
693. 721. 749. 777. 805.
694. 722. 750. 778. 806.
695. 723. 751. 779. 807.
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