GMAT Tip: The Two Minute Rule

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The GMAT Tip of the Week is a weekly column that includes advice on taking the Graduate Management Admission Test, which is required for admission to most business schools. Every week an instructor from a top test prep company will share suggestions for improving your GMAT score. This week’s tip comes from Sean Selinger, founder of 800Score.

GMAT math questions can all be solved in two minutes or less. The GMAT doesn’t have a built-in calculator and doesn’t want to measure how good you are at basic math calculations. It wants to measure your math intuition. If it looks as if you need to do five minutes of calculations to solve the question, you are likely missing a shortcut. You should probably try to reduce or eliminate the need for exhaustive calculations.

How? It’s simpler than you think. Imagine, for example, a question that asks you to multiply 123 × 341. The answer choices are: A) 40,816 B) 41,943 C) 42,637 D) 42,755 E) 43,321.

Don’t just do the calculation. Stop and think. Take a look at the answer choices. Multiply the last digit in 123 by the last digit in 341. You get 3 x 1, or 3. Whatever the answer is, it has to end in 3. As luck would have it, only one answer choice ends in 3. The correct answer is B.

Sean Selinger is the founder of 800score, a test prep service for the GRE and GMAT since 1999. Selinger graduated from Cornell University and scored above the 99th percentile on the SAT and the GMAT.

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