more than 1 million copies sold worldwide

13th EDITION

REVIEW The only study guide by the creators of the test • More than 900 questions ®

from past GMAT exams • NEW! Companion website includes

50 Integrated Reasoning questions • Diagnostic section helps you assess

where to focus your test-prep efforts ~The ~ L ICIA

OFF uide G

®

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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

6 7 7 8 9 10 10 11 11 11 12 12 13

2.0 2.0 2.1 2.2 2.3 2.4 2.5

How to Prepare How to Prepare How Should I Prepare to Take the Test? What About Practice Tests? How Should I Use the Diagnostic Test? Where Can I Get Additional Practice? General Test-Taking Suggestions

14 15 15 15 16 16 16

3.0 3.0 3.1 3.2 3.3 3.4 3.5 3.6

Diagnostic Test Diagnostic Test Quantitative Questions Verbal Questions Quantitative and Verbal Answer Keys Interpretive Guide Quantitative Answer Explanations Verbal Answer Explanations

18 19 20 27 45 45 46 65

4.0 Math Review 4.0 Math Review 4.1 Arithmetic 4.2 Algebra 4.3 Geometry 4.4 Word Problems

106 107 108 120 127 140

5.0 5.0 5.1 5.2 5.3 5.4 5.5

Problem Solving Problem Solving Test-Taking Strategies The Directions Practice Questions Answer Key Answer Explanations

148 149 150 150 152 186 188

6.0 6.0 6.1 6.2 6.3 6.4 6.5

Data Sufficiency Data Sufﬁciency Test-Taking Strategies The Directions Practice Questions Answer Key Answer Explanations

268 269 270 272 274 292 293

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!

NEW

7.0 7.0 7.1 7.2 7.3 7.4 7.5 7.6

358 359 360 362 363 364 418 419

8.0 8.0 8.1 8.2 8.3 8.4 8.5 8.6

Critical Reasoning Critical Reasoning What Is Measured Test-Taking Strategies The Directions Practice Questions Answer Key Answer Explanations

496 497 498 498 499 500 539 540

9.0 9.0 9.1 9.2 9.3 9.4 9.5 9.6 9.7 9.8

Sentence Correction Sentence Correction Basic English Grammar Rules Study Suggestions What Is Measured Test-Taking Strategies The Directions Practice Questions Answer Key Answer Explanations

664 665 665 670 670 670 671 672 698 699

10.0 10.0 10.1 10.2 10.3 10.4

Integrated Reasoning Integrated Reasoning What Is Measured The Question Types Test-Taking Strategies The Directions

776 777 777 778 785 787

11.0 Analytical Writing Assessment 11.0 Analytical Writing Assessment 11.1 What Is Measured 11.2 Test-Taking Strategies 11.3 The Directions 11.4 GMAT速 Scoring Guide: Analysis of an Argument 11.5 Sample: Analysis of an Argument 11.6 Analysis of an Argument Sample Topics Appendix A Appendix B

788 789 789 790 790 791 793 797 829 832 833 833 834 835 836 837 838 839

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1.0  What Is the GMAT® Exam?

1.0 What Is the GMAT® Exam?

1.0 What Is the GMAT® Exam?

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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 5,200 graduate management programs at approximately 1,900 institutions worldwide. Using GMAT scores helps institutions select the most qualified applicants and ensure that the applicants they admit are up to the academic rigors of their programs. 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 profiles, so you may also find these profiles 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.

Myth -vs- FACT M – If I don’t score in the 90th percentile, I won’t get into any school I choose. F – Very few people get very high scores. Fewer than 50 of the more than 200,000 people taking the GMAT exam each year get a perfect score of 800. Thus, while you may be exceptionally capable, the odds are against your achieving a perfect score. Also, the GMAT exam is just one piece of your application packet. Admissions officers use GMAT scores in conjunction with undergraduate records, application essays, interviews, letters of recommendation, and other information when deciding whom to accept into their programs.

No matter how well you perform on the GMAT exam, you should contact the schools that interest you to learn more about them 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 offices, web sites, and materials 7

The Official Guide for GMAT® Review 13th Edition

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1.2 GMAT® Exam Format The GMAT exam consists of four separately timed sections (see the table on the next page). The test starts with one Analytical Writing Assessment (AWA) essay prompt, and you will have 30 minutes to type your essay on a computer keyboard. The AWA is followed immediately by the 30-minute Integrated Reasoning section, which features 12 question prompts in four different question formats. The test ends with two 75-minute, multiple-choice sections: the Quantitative section, with 37 questions, and the Verbal section, with 41. The 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 much too hard or too easy for you. The first question will be of medium difficulty. As you answer each question, the computer scores your answer and uses it—as well as your responses to any preceding questions—to select the next question.

Myth -vs- FACT M – Getting an easier question means I answered the last one wrong. F – Getting an easier question does not necessarily mean you got the previous question wrong. To ensure that everyone receives the same content, the test selects a specific number of questions of each type. The test may call for your next question to be a relatively difficult problem-solving item involving arithmetic operations. But, if there are no more relatively difficult problem-solving items involving arithmetic, you might be given an easier item. Most people are not skilled at estimating item difficulty, so don’t worry when taking the test or waste valuable time trying to determine the difficulty of the questions you are answering.

8

1.3 What Is the GMAT® Exam? What Is the Content of the Test Like?

The 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 different on the computer. When you take the test: • Only one question or question prompt at a time is presented on the computer screen. • The answer choices for the multiple-choice questions will be preceded by circles, rather than by letters.

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• Different question types appear in random order in the multiple-choice and Integrated Reasoning sections of the test. • 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.

Format of the GMAT® Exam Analytical Writing Analysis of an Argument Integrated Reasoning Multi-Source Reasoning Table Analysis Graphics Interpretation Two-Part Analysis

Questions

Timing

1

30 min.

12

30 min.

37

75 min.

41

75 min.

Total Time:

210 min.

Optional break Quantitative Problem Solving Data Sufﬁciency Optional break Verbal Reading Comprehension Critical Reasoning Sentence Correction

1.3 What Is the Content of the Test Like? The GMAT exam measures higher-order analytical skills encompassing several types of reasoning. The 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 different formats to make reasoned conclusions; the Quantitative section asks you to reason quantitatively using basic arithmetic, algebra, and geometry;

9

The Official Guide for GMAT® Review 13th Edition

and the Verbal section asks you to read and comprehend written material and to reason and evaluate arguments.

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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. The 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 difficulty comes from the required analytical abilities, which are developed over time. The questions in this book are organized by question type and from easiest to most difficult, but keep in mind that when you take the test, you may see different types of questions in any order within each section.

1.4 Integrated Reasoning Section The 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 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 online 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, please visit the Integrated Reasoning online component using your unique access code found in the back of this book.

1.5 Quantitative Section The 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 Sufficiency 10

1.6 What Is the GMAT® Exam? Verbal Section

Both are intermingled throughout the Quantitative section, and both 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.

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1.6 Verbal Section The GMAT Verbal section measures your ability to read and comprehend written material, and to reason and evaluate arguments. The Verbal section includes reading sections from several different 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. Three 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 The Analytical Writing Assessment (AWA) consists of one 30-minute writing task: Analysis of an Argument. The 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.

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The Official Guide for GMAT® Review 13th Edition

1.9 What Are the Test Centers Like?

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The 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 breaks—one after completing the Integrated Reasoning section and another between the Quantitative and Verbal sections. 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.

12

1.11 What Is the GMATÂŽ Exam? Test Development Process

Appendix A contains the 2011 percentile ranking tables that explain the distribution of GMAT scaled scores across all GMAT tests-takers during the period beginning July 2008 and ending JuneÂ 2011. These ranking tables do not include Integrated Reasoning scores.

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1.11 Test Development Process The 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, see mba.com.

13

5.3 Problem Solving Practice Questions

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147. A certain rectangular window is twice as long as it is wide. If its perimeter is 10 feet, then its dimensions in feet are (A)

by

(B)

by

(C)

2 by 4

(D)

3 by 6

(E)

by

as many boxes as each worker on the day

crew. If the night crew has

as many workers as the

day crew, what fraction of all the boxes loaded by the two crews did the day crew load? (A) (B) (C) (D)

X

(E)

Y

148. The diagram above shows the various paths along which a mouse can travel from point X, where it is released, to point Y, where it is rewarded with a food pellet. How many different paths from X to Y can the mouse take if it goes directly from X to Y without retracing any point along a path? (A)  6 (B)  7 (C) 12 (D) 14 (E) 17

149. If the operation is deﬁned by positive numbers x and y, then

for all

152. A restaurant meal cost \$35.50 and there was no tax. If the tip was more than 10 percent but less than 15 percent of the cost of the meal, then the total amount paid must have been between (A)

\$40 and \$42

(B)

\$39 and \$4 1

(C)

\$38 and \$40

(D)

\$37 and \$39

(E)

\$36 and \$37

153. In a weight-lifting competition, the total weight of Joe’s two lifts was 750 pounds. If twice the weight of his ﬁrst lift was 300 pounds more than the weight of his second lift, what was the weight, in pounds, of his ﬁrst lift? (A) 225

(A) 30

(B) 275

(B) 60

(C) 325

(C) 90

(D) 350

(D)

(E) 400

(E) 150. A bar over a sequence of digits in a decimal indicates that the sequence repeats indeﬁnitely. What is the value of (A)  0 (B)   (C)  1.2 (D) 10

?

154. A club collected exactly \$599 from its members. If each member contributed at least \$12, what is the greatest number of members the club could have? (A) 43 (B) 44 (C) 49 (D) 50 (E) 51

(E) 12 173

The Official Guide for GMAT® Review 13th Edition

155. If y is the smallest positive integer such that 3,150 multiplied by y is the square of an integer, then y must be

B 5 ft.

(A)  2

2 ft.

(B)  5 (C)  6

A

(D)  7 (E) 14

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156. If [x] is the greatest integer less than or equal to x, what is the value of ? (A) 3

(A) 39

(B) 4

(B) 40

(C) 5

(C) 42

(D) 6

(D) 45

(E) 7

(E) 46.5

157. If

, what is the value of

?

(A) –4 (B)

– 1

(C)  0 (D)  1 (E)  2

158. In the first week of the year, Nancy saved \$1. In each of the next 51 weeks, she saved \$1 more than she had saved in the previous week. What was the total amount that Nancy saved during the 52 weeks?

174

159. The trapezoid shown in the ﬁgure above represents a cross section of the rudder of a ship. If the distance from A to B is 13 feet, what is the area of the cross section of the rudder in square feet?

(A) \$1,326 (B) \$1,352 (C) \$1,378 (D) \$2,652 (E) \$2,756

160. In a certain sequence, the term xn is given by the formula

for all

, what is the value of x3 ? (A) 2.5 (B) 3.125 (C) 4 (D) 5 (E) 6.75

. If

and

will have a hundreds digit of 2 can be expressed as

.

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11. 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

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 or

average would be , 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. The median would be 5 and the average would be

(E) \$2,750

. Thus, for the

Algebra First-degree equations

value in III, the average equals the median.

Letting x represent the total value of the item, convert the words to symbols and solve the equation.

7% of value in excess of

13. 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

12. 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

(C) 160 (D) 180 (E) 200

Let the width of the rectangle be x. Then the length is 2x. Since the perimeter of a rectangle is twice the sum of the length and width, it follows that

III. 5

So, the length is 120.

(A)

II only

(B)

III only

(C)

I and II only

(D)

II and III only

(E)

I, II, and III 191

The Official Guide for GMATÂŽ Review 13th Edition

14. If

, which of the following could be a value

16. On Monday, a person mailed 8 packages weighing an average (arithmetic mean) of

of y ?

Tuesday, 4 packages weighing an average of pounds. What was the average weight, in pounds,

(A) â&#x20AC;&#x201C;11

of all the packages the person mailed on both days?

(B)

(A)

(C)

(B)

(D) 11

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(E) 22

(C)

Algebra Inequalities; Absolute value

Since

(D)

is equivalent to , or

(E)

, select the

value that lies between That value is

and

Arithmetic Statistics

.

Since average

.

,

the information about the two shipments of packages can be expressed as

15. At a supermarket, John spent

average

of his money on fresh

fruits and vegetables,

bakery products. If he spent the remaining \$6 on candy, how much did John spend at the supermarket?

on meat products, and

on

. The correct answer is A.

(A) \$60 17.

(B) \$80 (C) \$90

(A) 0.1

(D) \$120

(B) 0.111

(E) \$180

(C) 0.1211

Arithmetic Fractions

(D) 0.2341

The amount spent was

(E) 0.3

of the total, so the \$6 left was

of the total. It follows that

the total is (15)(\$6) = \$90. The correct answer is C.

192

pounds, and on

Arithmetic Operations on rational numbers

Calculate the squared and the cubed term, and then add the three terms.

Questions 75–83 refer to the passage on page 396. 75. Which of the following titles best summarizes the contents of the passage?

(A) amount of protein present in a meal

(A) Neurotransmitters: Their Crucial Function in Cellular Communication

(B) concentration of serotonin in the brain before a meal

(B) Diet and Survival: An Old Relationship Reexamined

(C) concentration of leucine in the blood rather than with the concentration of tyrosine in the blood after a meal

(C) The Blood Supply and the Brain: A Reciprocal Dependence

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76. According to the passage, the speed with which tryptophan is provided to the brain cells of a rat varies with the

(D) Amino Acids and Neurotransmitters: The Connection between Serotonin Levels and Tyrosine (E) The Effects of Food Intake on the Production and Release of Serotonin: Some Recent Findings

Main idea

Finding a title that best summarizes a passage requires examining the passage as a whole. This task is made easier by the fact that the second sentence of the first paragraph provides a topic sentence stating the main idea: In recent studies, however, we have discovered that the production and release in brain neurons of the neurotransmitter serotonin … depend directly on the food that the body processes. In the second paragraph, the authors cite the results of several studies relating neurotransmitter levels to eating meals and to injections of insulin. In the final paragraph, the authors discuss a study of the effect of a proteinrich meal on serotonin level. Thus, the correct title must show the relationship between food eaten and serotonin produced. A

The function of neurotransmitters is only briefly mentioned. B The passage does not discuss the relation between diet and survival. C There is no discussion of blood supply and the brain. D While tyrosine is briefly mentioned, this was not a main focus of the studies. E Correct. This title offers a summary of the article’s contents.

(D) concentration of tryptophan in the brain before a meal (E) number of serotonin-containing neurons

Supporting ideas

The phrase according to the passage suggests that the answer is likely stated in the passage. Look at the third paragraph, which discusses variations in the speed with which tryptophan is provided to the brain. Lines 41–44 state the more protein is in a meal … the more slowly is tryptophan provided to the brain. A Correct. The greater the amount of protein, the more slowly tryptophan is provided. B The relationship is not discussed in the passage, although the concentration of serotonin after a meal is measured. C While leucine and tyrosine are mentioned, their concentrations in the blood are not compared. D This relationship is not discussed in the passage, although the concentration of tryptophan after a meal is measured. E The researchers do not consider the number of neurons. The correct answer is A.

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The Official Guide for GMAT® Review 13th Edition

77. According to the passage, when the authors began their ﬁrst studies, they were aware that (A) they would eventually need to design experiments that involved feeding rats high concentrations of protein (B) tryptophan levels in the blood were difﬁcult to monitor with accuracy

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(C) serotonin levels increased after rats were fed meals rich in tryptophan (D) there were many neurotransmitters whose production was dependent on metabolic processes elsewhere in the body (E) serotonin levels increased after rats were injected with a large amount of tryptophan

Supporting ideas

The phrase according to the passage suggests that the answer is likely stated in the passage. Look at the first sentence of the second paragraph where the focus of the authors’ first studies is explained. The investigators wanted to see if an increase in serotonin levels would be observed after rats ate meals that changed tryptophan levels in the blood. Earlier research had already established that injecting tryptophan increased serotonin levels. A

The authors’ decision to add protein came later in their studies, after they had seen the effects of eating in general. B The passage does not identify any problems with monitoring tryptophan levels in the blood. C This was the hypothesis of the first experiment, so the authors could not have known it beforehand. D This point is irrelevant to the authors’ work; only one neurotransmitter, serotonin, is discussed. E Correct. Lines 9–12 show that this increase had already been observed. The correct answer is E.

462

78. According to the passage, one reason that the authors gave rats carbohydrates was to (A) depress the rats’ tryptophan levels (B) prevent the rats from contracting diseases (C) cause the rats to produce insulin (D) demonstrate that insulin is the most important substance secreted by the body (E) compare the effect of carbohydrates with the effect of proteins

Supporting ideas

The phrase according to the passage suggests that the answer is likely stated in the passage. Look at lines 22–26, which say We then decided to see whether the secretion of the animal’s own insulin similarly affected serotonin production. We gave the rats a carbohydrate-containing meal that we knew would elicit insulin secretion. These sentences together show that the authors gave carbohydrates to the rats to cause the rats to secrete insulin. A

Lines 26–29 show that the carbohydrate increased the blood tryptophan level. B Preventing disease was not part of the study. C Correct. The authors had already tried injecting insulin; they then gave the rats carbohydrates to stimulate insulin production. D The authors make no such claim about insulin. E The study involving protein came later, so this could not have been the reason for giving the rats carbohydrates. The correct answer is C.

79. According to the passage, the more protein a rat consumes, the lower will be the (A) ratio of the rat’s blood-tryptophan concentration to the amount of serotonin produced and released in the rat’s brain (B) ratio of the rat’s blood-tryptophan concentration to the concentration in its blood of the other amino acids contained in the protein

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(C) ratio of the rat’s blood-tyrosine concentration to its blood-leucine concentration (D) number of neurotransmitters of any kind that the rat will produce and release (E) number of amino acids the rat’s blood will contain

Supporting ideas

The phrase according to the passage suggests that the answer is likely stated in the passage. In lines 41–43, the authors state: The more protein is in a meal, the lower is the ratio of the resulting bloodtryptophan concentration to the concentration of competing amino acids …. A

While lower levels of blood-tryptophan lead to lower serotonin levels, the relationship is not discussed in terms of a ratio. B Correct. Lines 41–43 show this to be the correct answer choice. C This relationship is not demonstrated in the passage. D This point is not made in the passage. E Lines 38–40 explain that consumption of protein increases blood concentration of the other amino acids much more …. Since proteins are made up of amino acids, eating protein would logically increase the number of amino acids.

80. The authors’ discussion of the “mechanism that provides blood tryptophan to the brain cells” (lines 34–35) is meant to (A) stimulate further research studies (B) summarize an area of scientiﬁc investigation (C) help explain why a particular research ﬁnding was obtained (D) provide supporting evidence for a controversial scientiﬁc theory (E) refute the conclusions of a previously mentioned research study

Logical structure

To find the purpose of this discussion, look at the context in which this reference occurs. At the beginning of the third paragraph, the authors note that, surprisingly, adding protein led to lower brain tryptophan and serotonin levels. The question is why were the levels lowered? The answer lies in the mechanism cited in lines 34–35. Therefore, the discussion of the mechanism is meant to explain a surprising research finding. A B

No further studies are mentioned. There are summaries of several studies, but there is no summary of an entire area of scientific investigation. C Correct. The mechanism helps explain the surprising finding about lower brain tryptophan and serotonin levels. D No theory is advanced, nor is any evidence about it provided. E There is no attempt to refute any other study. The correct answer is C.

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The Official Guide for GMAT® Review 13th Edition

81. According to the passage, an injection of insulin was most similar in its effect on rats to an injection of (A) tyrosine (B) leucine (C) blood (D) tryptophan (E) protein

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Supporting ideas

Since the question refers to information given in the passage, the answer can be found by careful reading. In order to find an injection with a similar effect, look first at the effect of injecting insulin. In lines 20–22, the authors state that injecting insulin … caused parallel elevations in blood and brain tryptophan levels and in serotonin levels. The only other reference to injection occurs earlier in lines 10–13 where rats injected with tryptophan had increased serotonin levels; injecting tryptophan would obviously cause tryptophan levels to increase. Thus, the effects of injecting insulin were similar to the effects of injecting tryptophan. A

No evidence suggests that tyrosine injection would have similar effects. B The studies did not involve injecting leucine. C The studies did not involve injecting blood. D Correct. According to the passage, injecting tryptophan raises serotonin and tryptophan levels just as injecting insulin does. E The studies involved eating protein, not injecting it; eating protein did not raise serotonin levels. The correct answer is D.

82. It can be inferred from the passage that which of the following would be LEAST likely to be a potential source of aid to a patient who was not adequately producing and releasing serotonin? (A) Meals consisting almost exclusively of protein (B) Meals consisting almost exclusively of carbohydrates (C) Meals that would elicit insulin secretion (D) Meals that had very low concentrations of tyrosine (E) Meals that had very low concentrations of leucine

Inference

Since this question asks for an inference, the answer is not directly stated in the passage; it must instead be derived from the information given. What kind of meals would NOT help a patient with low serotonin levels? Meals that increased serotonin would help the patient; meals that lowered serotonin would not. According to the last sentence in the passage, the more protein in a meal, the less serotonin subsequently produced and released. Therefore, high-protein meals would be LEAST likely to help the patient. A Correct. Meals with very high levels of protein would tend to lower serotonin and thus to be less beneficial for the patient with inadequate serotonin levels. B When rats ate a carbohydrate-containing meal, serotonin increased (lines 25–29). Therefore, these meals would tend to raise serotonin levels and so help the patient. C In the study, meals that elicited insulin secretion raised serotonin levels. D Since tyrosine is an amino acid found in protein, meals low in tyrosine would be low in protein and so would tend to raise serotonin levels and help the patient. E Since leucine is an amino acid found in protein, meals low in leucine would be low in protein and so would tend to raise serotonin levels and help the patient. The correct answer is A.

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The Official Guide for GMAT® Review 13th Edition

Read the question thoroughly to make sure you understand what is being asked. Then consider each phrase, statement, numerical value, or algebraic expression to learn what information in the table you need to make your decision. In analyzing the table, you may need to, for example, • determine statistics such as mean, median, mode, or range • determine ratios, proportions, or probabilities • identify correlations between two sets of data

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 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. The blanks should be filled 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 find 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 first bar indicates that 7 units were sold on Monday of Week 1. Units Sold in Week 1 10 Units Sold

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• compare an entry’s rank in two or more of the table’s categories

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10.2 Integrated Reasoning The Question Types

The same information is presented below as a line graph. Each point indicates the total number of units sold on a given day. The 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. Units Sold in Week 1

Units Sold

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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. The line graph shows what percent of the total units were sold on each day. The scale for the percentages is shown on the right axis. units sold percent of total

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Units Sold in Week 1

Units Sold

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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 offered for sale. A dotâ&#x20AC;&#x2122;s position relative to the vertical axis indicates the productâ&#x20AC;&#x2122;s price, and its position relative to the horizontal axis indicates its weight. Thus, the product that weighs 1.0 kg costs approximately 32,000 rupees.

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price in rupees

Products for Sale by Price and Weight 35,000 30,000 25,000 20,000 15,000 10,000 1.0

1.5 2.0 weight in kg

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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. Thus, in the scatterplot below, the trend line indicates a negative correlation between price and weight among the products represented on the graph. The closer the data points are to a trend line, the more strongly the data are correlated. Products for Sale by Price and Weight price in rupees

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0.5

35,000 30,000 25,000 20,000 15,000 10,000 0.5

1.0

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2.5

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In a bubble graph, each data point is represented by a circle. The center of the circle indicates the values on the horizontal and vertical axes, as in a scatterplot. The 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. Thus, 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. Products for Sale by Price, Weight, and Number Sold price in rupees

35,000 30,000 25,000 20,000 15,000 0.9

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10.2 Integrated Reasoning The Question Types

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Other common kinds of graphics do not use vertical and horizontal axes. These include pie charts, flow 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. The 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 Thursday, 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. Thus, Tuesdayâ&#x20AC;&#x2122;s sales comprised more than 25% of total sales. Week 1 Sales by Day Friday

Monday

Thursday

Wednesday

Tuesday

A flow 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 flow of the process. Flow charts generally progress from top to bottom or from left to right. In the simple flow chart below, rectangles indicate steps to be completed. The 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. Yes

Prepare contract for consultant

New consultant?

Append tax forms

Mail contract

No

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 staff and cleaning staff both report to the kitchen manager, and the serving staff report to the serving staff manager. 783

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restaurant manager

kitchen manager

chef

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food preparation staff

serving staff manager

cleaning staff

serving staff

For all kinds of Graphics Interpretation questions, be sure to read the question carefully to be sure you understand what is being asked. Then 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 filled. Both blanks must be filled 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. These 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 different components in a mixture

• determine something that would be lost and something that would be gained in a trade-off

• find the maximum number of two different products that could be purchased within a certain budget • identify a first action and a second action that together would bring a company into compliance with a new rule

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The following appeared in a memorandum from the assistant manager of Pageturner Books: “Over the past two years, Pageturner’s proﬁts 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 proﬁts 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 proﬁtability.”

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11.6 Analytical Writing Assessment Analysis of an Argument Sample Topics

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 ﬁnancial beneﬁts, farmers in this country should begin growing it.” Discuss how well reasoned … etc.

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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 ﬁve years. If Aurora is to proﬁt 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 Diversiﬁed Manufacturing: “Managers at our central ofﬁce 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 ofﬁce operations: “During a two-week study of postal operations, the Presto City post ofﬁce handled about twice as many items as the Lento City post ofﬁce, 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 ofﬁce. Therefore, the postmasters at these two ofﬁces should exchange assignments: the Presto City postmaster will solve the problems of inefﬁciency and customer dissatisfaction at the Lento City ofﬁce while the Lento City postmaster learns ﬁrsthand the superior methods of Presto City.” Discuss how well reasoned … etc.

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