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Go ahead, roll your eyes… but it’s GMAT quantitative reasoning, not GMAT math


If you’ve struggled with the GMAT quant section more than you think you should, this blog post is for you. If you’ve ever said, “I’ve always been a really good math student, but I can’t understand why the GMAT quant is so hard for me!” – then this post is definitely for you.

In my former life as a PhD student, I spent far too much time learning about the statistical science underneath standardized testing, known as psychometrics. My nearly three-year PhD odyssey didn’t result in much other than some grey hairs and a “thank you for playing!” Master’s degree in education, but I did experience a few things that probably helped me become a better GMAT and GRE tutor.

This is a story about one of those things – and at the time, I never would have guessed that it would be useful for my GMAT and GRE students.

In my first year as a PhD student, I went to a psychometrics conference, populated by academics and employees of major standardized testing organizations, including ETS (makers of the GRE and TOEFL) and GMAC (creators of your beloved GMAT). I attended a presentation by a high-ranking GMAT psychometrician, who discussed… well, nevermind that part, I’ll put you right to sleep if I start talking about it.

Anyway, here’s the useful bit: somebody in the audience asked a question about the “math section of the GMAT.” The GMAT psychometrician interrupted him politely: “Excuse me,” he said, “there is no math section on the GMAT. There’s only quantitative reasoning.”

I probably rolled my eyes. “What a dick,” I thought, “why would he make a big deal out of that? It’s math. S#!t, I’ve been teaching it for a decade. Whatever, dude.”

Sure, maybe the GMAT psychometrician wasn’t picking the best moment to make a big deal out of it, but he absolutely had a point. In the few years since I attended that conference, I’ve realized that my students – particularly Americans – actually perform better on the quant section of the GMAT when they stop thinking of it as “math” and start thinking of it as “quantitative reasoning.”

Here’s the thing: in the United States, “math” knowledge – at least through the high school level – is typically taught as sequences of mechanical steps that you need to memorize and follow. Throughout much of my public school education, our daily homework would consist of 10 or 20 nearly identical math problems. The problems were usually so similar that there was no reason to think about what any of it meant. If you could follow instructions, you’d get an A – even if you had absolutely zero understanding of the underlying mathematical concepts.

As a result, most Americans think that the word “math” just refers to a boring series of steps that you follow. Sadly, we don’t think of mathematics as a way of thinking, or as a set of useful tools for reasoning our way through useful problems. There are, of course, plenty of exceptions, but the overwhelming majority of Americans have learned math in a way that strips it of its logic, meaning, and intuition.

So it’s no surprise that I hear this over and over from GMAT test-takers, especially Americans: “I’m a really good math student, but I can’t understand why the GMAT is so hard for me!”

Obviously, there are a ton of reasons why somebody might struggle with the GMAT quant section, but plenty of GMAT test-takers make the subtle mistake of trying to learn too many formulas, memorize too many steps, and drill too many mechanical aspects of mathematics. The GMAT, for all of its flaws, brilliantly twists 10th-grade math into a hard-to-penetrate – or at least a hard-to-quickly-penetrate – tangle of logic.

In other words: if you’re trying to blindly apply mechanical techniques to GMAT quant questions above the 500 or 600 level, the exam will eat you for breakfast.

Let’s look at an example (with apologies for the blurry fractions):

Which of the following is greatest?

GMAT blog example quantitative reasoning

If you think of this as a mechanical “math question,” you’ll follow some well-worn steps here: find some common denominators, add the fractions, and THEN compare the sums.

Go ahead and try it if you’d like. If you can correctly solve the question that way in two minutes or less, I’ll give you a cookie.

But if you’re thinking of the GMAT as “quantitative reasoning” – with or without the eye-roll – then maybe you’ll try something quicker, smarter, and less arithmetic-intensive. In this case, we’re just looking for the greatest value – and we don’t care what that value actually is, as long as we know that it’s larger than the other four answer choices.

So since the question is just asking for the greatest of the five answer choices, you can just compare pairs of answer choices, and knock off anything that’s the smaller of the two. Let’s start with D and E. It’s easy to see why E is larger than D once you notice that 1 – ½ = ½, so D is gone.

Similarly, B looks a lot like E, except that the denominators in B are squared – and since larger denominators mean that the fractions must be smaller, we can cross off B. The same argument holds for C – it’s clearly smaller than E as well. And then A has smaller denominators than E – so A is your answer.

No computation required, right? If you’re approaching this wisely, you barely need to lift your pen.

So if you’re thinking of the GMAT quant section as a set of narrow mathematical tasks – formulas that need to be memorized, or boring-ass steps that need to be followed – then you’re barking up the wrong tree, at least if you want an elite GMAT quant score. Once you start looking for opportunities to apply flexible logic and identify multiple solution paths, then you’re on the right track.

If any of this strikes a nerve, then it might not be a bad idea to stop yourself whenever you start thinking about the GMAT “math section.” Roll your eyes at yourself if you’d like, but thinking of the GMAT quant section as “quantitative reasoning” might help you embrace the flexibility and logic you’ll need for a top GMAT quant score.

GRE vs. GMAT, part IV: GRE study materials

Thanks in large part to MBA programs’ increasing appetite for the GRE, I’ve had a surge in GRE tutoring inquiries over the past year or so.  The GMAT is still king in the MBA admissions world—and probably will be for a long time—but a surprisingly large proportion of my time is spent on the GRE now.  Even though I actually have a longer history with the GRE than with the GMAT (and I’ll feel really really old if I tell you exactly how long that is), I’ve never seen this level of interest in the GRE among MBA applicants.  So congratulations, GRE:  you’re not winning yet, but you’re in the game now.

In a series of earlier blog posts, I did my best to figure out what types of MBA applicants might be better off taking the GRE instead of the GMAT.  If you really want to read the whole series, I would recommend starting with Part I, but here’s the oversimplified summary:  since MBA programs are more familiar with the GMAT—and since the GRE includes those annoying vocabulary questions—relatively few MBA applicants will actually gain a significant advantage by taking the GRE.  Sure, some applicants are much better off with the GRE, but it’s tough to argue that one test is unambiguously “better” than the other if you’re shooting for a top MBA program.

I did, however, accidentally leave one factor out of the discussion in those three blog posts:  the relatively limited availability of GRE test-prep materials.  If you’re choosing between the GRE and the GMAT and you think that you’ll need a lot of repetition in order to reach your score goals, then the GMAT might be a better bet.

From a test-taker’s perspective, one of the GMAT’s best qualities is that it isn’t difficult to keep yourself busy with high-quality study materials, even if you’re facing a protracted battle with the GMAT beast.  We’re blessed with four full, official GMATPrep practice tests, a beefy bank of nearly 500 additional questions in the GMATPrep Question Pack (which can be used to cobble together additional “fake tests”), and somewhere around 750 quant and 600 verbal questions in the GMAT official guides (including the official GMAT quant and verbal review guides).

If that isn’t enough, we also have the crusty old GMAT paper tests, older editions of the GMAT official guides that can yield a few hundred additional questions, the (deeply flawed) GMAT Focus tests, and a nearly limitless supply of LSAT questions if you need some extra work on CR and RC.  And of course, there’s a healthy ecosystem of GMAT test-prep firms that will happily provide additional materials and practice tests, albeit of lamentably variable quality. 

The bottom line:  it would take literally hundreds of hours of studying to exhaust the supply of worthwhile GMAT materials.  I’ve seen it happen, but it’s a rarity.

Unfortunately, we aren’t nearly as well-endowed when it comes to high-quality GRE materials.  (And yes, I really did just use the phrase “well-endowed” on a GMAT blog.  Judge if you must.)  The official GRE software includes only two full, adaptive practice tests—which means that you should use them very carefully if you’re planning to take the GRE.  There are a total of three additional paper-based GRE practice tests available in the GRE official guide and in an odd corner of the GRE website, but paper-based tests do not even begin to mimic the experience of taking an actual, computer-adaptive GRE exam, and therefore are of somewhat limited value.

The GRE looks even worse when we tally the questions that appear in the GRE official guides.  Even if we include the GRE’s new verbal and quantitative reasoning guides (in addition to the GRE Official Guide), we still have only 210 additional verbal questions and 210 additional quant questions – far fewer than are available for the GMAT.  Sure, it’s possible to supplement the official GRE materials with “knockoff” materials from test-prep firms, but these materials are rarely as useful as official GRE or GMAT questions.  The old GRE official guide (out of print, but still generally available online) is still a decent source of quant practice questions, but the vocabulary questions are completely obsolete, and the quant questions are generally easier than the ones you’ll encounter on an actual, computerized GRE.

So at best, we have maybe half as many high-quality GRE test questions as we do GMAT questions, depending on how you want to define “high-quality.”  If you’re a naturally gifted test-taker, then you probably won’t need that much practice, and the lack of good GRE materials is a non-issue.  But if you’re looking for a huge score improvement, you might have an easier time moving forward on the GMAT than on the GRE.

To be fair, the GRE just experienced a major overhaul in 2011, and because it is incredibly expensive for testing companies to develop operational exam questions, it normally takes quite a few years before retired questions are publicly released.  (The GMAT, after all, only began to sell the Exam Pack, which includes two additional adaptive practice tests, in 2013.)  I can’t blame the GRE’s creators at all:  their job is to create a valid exam, not necessarily to provide us with materials that help us clobber that exam.  But if you already know that you have a long road ahead of you and you’re not sure which test to take, the GMAT’s relative generosity with retired questions might be a decent reason to steer clear of the GRE.