GMAT Math Content (Beginner's Guide)
February 11, 2008
Like all standardized exams, the content tested on the GMAT is extremely consistent. (It has to be, or it wouldn't be standardized.) That is especially true on the Quantitative section.
To the novice, however, it may be clear exactly what math is tested on the GMAT. Much of the content overlaps with what appears on the SAT, an still more is similar to material on the GRE. A lot of the skills are taught in middle school, particularly in Pre-Algebra, Algebra, and Geometry classes.
What's tricky, though, is defining the range of content any further. A good deal of what you learned in your middle school or high school Geometry class is not on the GMAT, and there are some topics that you may have never been exposed to before. That doesn't mean they are particularly difficult, only that you'll be learning them from scratch.
This article doesn't have room enough to contain a detailed outline of the math content tested on the GMAT, but there are several places you can look for those.
For a very, very brief overview, look at the first set of bullet points in this article. It gives you a good idea of the areas that are tested, and one way to categorize them.
If you'd like a couple dozen pages that go over the various subject areas in a very dry manner, try the Math Review section of The Official Guide to GMAT Review. I don't particularly recommend that chapter as a resource, but it is useful in that it catalogues the types of questions you are likely to see, and it is written from the perspective of the testmaker.
I've contributed to the field as well; my Total GMAT Math contains much more detailed coverage of every subject area and just about every type of question on the exam.
Drawing the Line
Because GMAT math content is so specific to the GMAT, it is generally not helpful to use study resources that were not designed for GMAT Prep. For example, in a article several months ago I pointed readers to an online Algebra textbook. However, to make it worthwhile, you'll notice I had to pick and choose among the sections. If I did the same thing with a Geometry book, I'd probably have to be choosier still.
To give just some examples of how the GMAT is unique:
- The GMAT tests quadratic equations of the form ax^2 + bx + c, but the value of a is almost always 1.
- You'll see questions that address standard deviation, but you don't need to know how to solve for standard deviation.
- You need to know the side ratios of triangles with angle ratios of 45:45:90 and 30:60:90, but no others; despite coming that close to trigonometry, the GMAT goes no farther.
- There is plenty of arithmetic on the test, but the GMAT almost never requires that you do calculations with numbers larger than 144.
What's more, about one-third of GMAT Math problems are in the Data Sufficiency format, which is only found on the GMAT. I'll cover that question type in my next "Beginner's Guide" article.
Ultimately, it's up to you to learn where the lines are drawn. The resources I mentioned above can help, but your personal practice (and the way you think about what you are practicing) is the best way to learn what concepts recur, how they present themselves, and how you need to react to them.
GMAT Math Resources
Most GMAT Math books are not very good at presenting all of the content you need in a concise form. Many of the test prep books you'll find are geared toward strategies, tricks, and practice problems, and they presuppose a level of content knowledge that you may not have.
As I've pointed out, non-GMAT materials have their problems as well: It's no fault of the authors of those books, but the scope of an algebra or geometry textbook isn't the same as that of a GMAT book.
I think Total GMAT Math is the best resource out there that walks you through all the content you need to know; if you'd prefer something that you can put on your bookshelf, the best resource you're likely to find at your neighborhood Barnes & Noble is Kaplan's GMAT Math Workbook.
If you do use other materials, make sure that the content you are learning from them matches up to what you see in the Math Review section of the Official Guide; if the testmaker is going to be so kind as to tell you what is on the test, take full advantage of it, and focus your efforts in that direction!
About the author: Jeff Sackmann is a GMAT tutor based in New York City. He has created many resources for GMAT preparation, including the popular Total GMAT Math and Total GMAT Verbal, as well as 1,800 practice GMAT math questions.