If you’ve been studying for the GMAT, you’ve probably encountered situations that require knowledge of quadratic equations and how they work. In so doing, you’ve also probably memorized the following three equivalencies: (x + y)2 = x2 + 2xy + y2 (x – y)2 = x2 – 2xy + y2 (x – y)(x + y) = x2 – y2 Knowledge of these three equations will, without a doubt, come in handy on…

One of the most widespread mistakes I see students make on Data Sufficiency concerns the information they consider when evaluating a statement. To properly determine whether a statement is sufficient, you must be focused on using only the information given. If, for example, a statement only tells you that -10 < x < 10, but says nothing else, then you can’t assume that x is an integer, and you…

Recently, while riding the subway, I saw an ad that captures one of the most common GMAT Sentence Correction errors. If you live in New York, you’ve probably seen it: “This poster can make you happier than any other on the subway.” Though I’m sure most subway riders have more pressing concerns than the nuances of English grammar, this ad caught my attention because, much…

An enduring myth among many test-takers (GMAT and otherwise) is that standardized test preparation is simply a matter of memorizing a few rules and shortcuts and implementing these tricks on test day. This belief is only reinforced by large test-prep companies like The Princeton Review and Kaplan, whose curriculum is oriented around such superficial techniques. Unfortunately, I’ve had to break the news to a few…