GMAT Tip: When to Guess or Skip Questions

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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 Mike McGarry, lead GMAT content creator at Magoosh.

Despite the best preparation, things sometimes don’t go according to plan, even on the GMAT. What should you do in the following worst-case scenarios?

“I understand the question enough to eliminate a few answer choices, but can’t determine the correct answer.”

Then the odds are in your favor for guessing. Never leave such a question blank. Always guess randomly from the remaining answer choices.

“I am unable to eliminate a single answer and I’m running out of time. Should I guess randomly or leave the question blank?”

It turns out that GMAC itself did some sophisticated research on this question. The results, surprisingly, depend on which section of the test is concerned. What follows relies on research conducted by Eileen Talento-Miller and Fanmin Guo for their paper, “Guess What? Score Differences with Rapid Replies Versus Omissions on a Computerized Adaptive Test.”

On the verbal section, GMAC’s data showed no significant score difference between randomly guessing and omitting the same number of questions. This data has powerful implications for “end game” strategies on the verbal section. Suppose that on the verbal section, you realize: “I have only three minutes left for five questions.” Don’t panic. Give full focus to the question in front of you and answer it to the best of your abilities. Your job in the last minutes of verbal should be to answer each question to the best of your abilities, however long it takes. Don’t worry about needing to race through, checking off random answers. On average, that will give you no different a score than if you were to leave them blank.

On the quantitative section, the advice is different. Leaving questions blank hurts you more than does answering a question incorrectly. The better your overall score, the more costly a blank question is, compared to a wrong answer. So the strategy for quantitative is: Skip nothing. If you’re stuck and can’t eliminate anything, at least guess randomly. Under no circumstances should you leave the question blank, even if that means random guessing in a last, mad dash to complete the section’s final questions.

To sum up: Guess when you can eliminate one or more answers; don’t sweat unanswered questions on verbal, but give an answer to everything on quantitative, even if this entails blind guessing.

Mike McGarry scored in the 99th percentile on the GMAT. He is an expert in standardized test preparation, and has been a teacher for over 20 years. McGarry earned both a bachelor’s degree in physics and a master’s in comparative religion from Harvard University.

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