Kaplan GRE & GMAT Exams Math Workbook, Third Edition (Kaplan GMAT Math Workbook)
Chapter OneBeen there, done that.If you're considering applying to graduate school or business school, then you've already seen all the math you need for both the GRE and the GMAT. You would have covered the relevant math content in junior high. In fact, the math that appears on the GRE and GMAT is almost identical to the math tested on the SAT or ACT. You don't need to know trigonometry. You don't need to know calculus. No surprises -- it's all material you've seen before. The only problem is, you may not have seen it lately. When was the last time you had to add a bunch of fractions without a calculator?No matter how much your memories of junior high algebra classes have dimmed, don't panic. The GRE and the GMAT test a limited number of core math concepts in predictable ways. Certain topics come up in every test, and, chances are, these topics will be expressed in much the same way; even some of the words and phrases appearing in the questions are predictable. Since the tests are so formulaic, we can show you the math you're bound to encounter. Some practice on testlike questions, such as those in the following chapters, will ready you for the questions you will see on the actual test.Here is a checklist of core math concepts you'll need for the GRE and GMAT. These concepts are vital, not only because they are tested directly on every GRE and GMAT, but also because you need to know how to perform these simpler operations in order to perform more complicated tasks. For instance, you won't be able to find the volume of a cylinder if you can't find the area of a circle. We know the math operations on the following list are pretty basic, but make sure you know how to do them.GRE and GMAT Math BasicsAdd, subtract, multiply and divide fractions. (Chapter 2)Convert fractions to decimals, and vice versa. (Chapter 2)Add, subtract, multiply, and divide signed numbers. (Chapter 2)Plug numbers into algebraic expressions. (Chapter 3)Solve a simple algebraic equation. (Chapter 3)Find a percent using the percent formula. (Chapter 2)Find an average. (Chapter 2)Find the areas of rectangles, triangles, and circles. (Chapter 5)How Math is Scored on the GMATThe GMAT will give you a scaled quantitative score from 0 to 60. (The average score is 30.) This score reflects your performance on the math portion of the test compared to all other GMAT test takers.You will also receive an overall score that reflects your performance on both the math and the verbal portions of the test. This is a scaled score from 200 to 800.How Math is Scored on the GREThe GRE will give you a scaled quantitative score from 200 to 800. (The average score is 500.) This score reflects your performance on the math portion of the GRE compared to all other GRE test takers.Test OverviewThe GRE and the GMAT are pretty similar in terms of the math they test. However, there are significant differences in the way the tests are administered. The GMAT and GRE are now available only as a Computer Adaptive Test, or CAT. You take this test on a computer at special centers. Here's a quick overview of the math sections of the GRE and GMAT CAT.Problem Solving Questions on the GRE and GMATProblem Solving questions are the simplest you will see on either test. You are given a question (and sometimes an accompanying chart or diagram) and asked to choose the correct answer from a list of five answer choices.Quantitative Comparison Questions on the GREQuantitative Comparisons are found only on the GRE. You are given two quantities, one in Column A, and one in Column B, and you must decide if one in particular is larger, whether they are the same size, or whether you need more information to make the comparison. There are four answer choices, which are the same for every Quantitative Comparison question. Sometimes you will be given additional information about the quantities being compared. This will be centered above the columns.Data Sufficiency Questions on the GMATData Sufficiency questions are found only on the GMAT. In Data Sufficiency, a question is followed by two statements containing certain data. Your task is to determine whether the data provided by the statements are sufficient to answer the question. All Data Sufficiency questions have the same five answer choices.Math on the GMAT CATOne Quantitative section:There are 37 questions to be done in 75 minutes.Approximately two-thirds of the questions will be in the Problem Solving format, and the remaining questions will be in the Data Sufficiency format.About 10 of the questions in the GMAT CAT math section will be experimental questions. These are questions that are being tested for use in future tests, and are not scored. However, there is no way of telling the experimental questions from the scored questions around them, and so you should treat all questions as if they are scored.Math on the GRE CATOne Quantitative section:There are 28 questions to be done in 45 minutes.Approximately half of the questions will be in the Quantitative Comparison format and the remaining questions will be in the Problem Solving format. About a quarter of the Problem Solving questions will ask you to interpret a set of charts or graphs.Math ContentThe GMAT and GRE test similar skills and knowledge. As we mentioned, it's basically junior high school level math. The emphasis is slightly different between the tests, though. Most test takers find the math on the GMAT to be slightly more challenging.Here's how the approximate number of questions break down by content area for the two tests. (By the way, this book contains chapters devoted to each of these subject areas, so you can focus on the most relevant material.)GMAT Math by Subject AreaArithmetic -- About half of all questions.Algebra -- About a quarter of all questions.Geometry -- About a sixth of all questions.Graphs, logic questions, and other miscellaneous question types occur from time to time.About half of all questions are presented in the form of word problems.GRE Math by Subject AreaArithmetic -- About a third of all questions.Algebra -- About a sixth of all questions.Geometry -- About a third of all questions.Graphs -- About a sixth of all questions.About a quarter of all questions are presented in the form of word problems.Computer Adaptive TestingThe GMAT and GRE CATs are a little different from the paper-and-pencil tests you have probably seen in the past.You make your way through the GMAT and GRE CATs by pointing and clicking with a mouse -- in fact, the tests are mouse-only. You won't use the keyboard in the math portions of the tests. Each test is preceded by a short tutorial that will show you exactly how to use the mouse to indicate your answer and move through the test. If you have used a computer and mouse before, you will probably find the procedure to be very simple.How a CAT Finds Your ScoreThese computer-based tests "adapt" to your performance. This means the questions get harder or easier depending on whether you answer them correctly or not. Your score is not directly determined by how many questions you get right, but by how hard the questions you get right are.When you start a section the computer:Assumes you have an average score.Gives you a medium-difficulty question.If you answer a question correctly:Your score goes up.You are given a harder question.If you answer a question incorrectly:Your score goes down.You are given an easier question.After a while you will reach a level where most of the questions will seem difficult to you. At this point you will get roughly as many questions right as you get wrong. This is your scoring level. The computer uses your scoring level in calculating your scaled score.Another consequence of the test's adaptive nature is that for the bulk of the test you will be getting questions at the limit of your ability. While every question is equally important to your final score, harder questions generate higher scores and easier questions lower scores. You want to answer as many hard questions as possible. This is a reason to concentrate your energies on the early questions. Get these right and you are into the harder questions, where the points are. The sooner you start to see harder questions, the higher your final score is likely to be.There are a few other consequences of the adaptive nature of the test that you should consider.There is no preset order of difficulty; the difficulty level of the questions you're getting is dependent on how well you have done on the preceding questions. The harder the questions are, the better you are doing. So, if you seem to be getting only hard questions, don't panic: It's a good sign!Once you leave a question, you cannot return to it. That's it. Kiss it good-bye. This is why you should never rush on the CAT. Make sure that you have indicated the right answer before you confirm it and move on. The CAT rewards meticulous test takers.In a CAT you must answer a question to move on to the next one. There's no skipping around. If you can't get an answer, you will have to guess in order to move on. Consequently, intelligent guessing can make the difference between a mediocre and a great score. Guess intelligently and strategically -- eliminate any answer choices that you can determine are wrong and guess among those remaining. The explanations to the questions in this book will demonstrate techniques for eliminating answer choices strategically.One final, important point. There is a penalty for unanswered questions on the CAT. Every question you leave unanswered will decrease your score by a greater amount than a question that you answered incorrectly! This means that you should answer all the questions on the test, even if you have to guess randomly to finish a section.Copyright © 2002 by Kaplan, Inc.