As Veritas Prep's Director of Academic Programs, Brian Galvin runs all of the company's GMAT prep services.
The writers of the GMAT are tasked with a fairly difficult challenge -- using fairly basic, high-school level math and verbal skills, they must create questions that will elicit incorrect answers from some of the most intelligent people on the planet. If you're even interested in taking the GMAT, you've either graduated from or intend to shortly graduate from a four-year university, and you likely have at least a few years of quality work experience, plus the desire to spend two years and a healthy amount of money to obtain a Master's degree. People like you, quite frankly, are difficult to consistently outsmart!
The writers, however, are quite sharp themselves, and realize astutely that intelligent people have learned over time to make time-saving assumptions that allow them to consistently perform at a high level without spending undue time to do so. As a multitasker, you allow yourself to take shortcuts that can be your undoing on the GMAT.
Consider this question:
How many even integers exist within the range -9 to 9?
As you attempt to answer this quickly, you'll likely note that the range is symmetrical, and that by recognizing 2, 4, 6, and 8 as the positive even integers, you can multiply by 2 to account for all of the negative integers. Accordingly, you might choose 8 as your answer.
In doing so, however, you probably forgot about 0, one of the devilish devices that the GMAT uses to bait unaware test-takers. Zero, quite literally, means "nothing," making it an easy number to overlook. Furthermore, it's neither positive nor negative (which mean "greater than zero" and "less than zero," respectively), so it has no opposite in a situation like this when you might try to bank on the symmetry of the data set to shorten your workload.
To be successful on the GMAT, be keenly aware of the presence of the number 0 in any problems where it could appear. Much like a talented, multi-dimensional football player can cause defenses to always seek for his jersey number on the field ("Where's number 5? Who's covering number 5?"), the number 0 should keep you alert, as well. Ask yourself how 0 might factor in to each situation you face (it's nonnegative but not positive; it's even; when multiplied, it makes the entire product 0), as it just may be the difference-maker that the authors of the test need to keep your score down.
For more GMAT prep and MBA admissions advice, visit Veritas Prep.
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