How to Solve GMAT Data Sufficiency Questions and Staying on Pace

Posted by Maryam Amr on 9/16/15 10:00 AM


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Blank.  It's test day, you’re staring at a data sufficiency question, and you’re drawing a blank.  You can feel the seconds slip by and you know you’re losing valuable time.  On test day, powering through this scenario and staying on pace could be the difference between scoring well enough to get into your target MBA program and needing to retake the exam.

What is Data Sufficiency?

The Quantitative section (75 minutes, 37 questions) of the GMAT consists of two question types:  Data Sufficiency and Problem Solving.  The GMAT data sufficiency questions present you with a prompt and two statements.  You must evaluate each of these statements individually to determine if either is sufficient to answer the question.  If they aren’t, you then combine the statements and again test for sufficiency.  It is considered the most difficult of GMAT question types, and if you’re not cognizant of the time elapsed, it can often be quite time-consuming!

Why is Pacing So Important?

The GMAT rewards those who can pace themselves in a few ways.  The first is that the GMAT heavily penalizes you if you don’t finish the exam.  Secondly, a string of incorrect responses will lower a score more than the same number of incorrect responses interspersed.  So, if you rush to finish the exam after falling behind, guessing on answers and making many mistakes in a row, you’re actually doing yourself harm.  This is why it’s very important not to fall behind during the exam.

Since the Quantitative section has 37 questions and gives you 75 minutes, your pace should be about two minutes per question.  As a GMAT tutor with Cambridge Coaching, I created a Five-Step strategy to stay on track when a Data Sufficiency question stumps you.

Five Steps to Pacing

Step 1: Assess the Situation

The two minutes per question is an average; some questions will require more time, some will require less.  Take quick stock of the time that has elapsed and divide by two.  This will give you the question number you should be on by now. (For example, if 20 minutes have passed, you should be on question #10). If you are already on question #12, you may have time to spend here. If you are only on question #8, you must really answer this question quickly and move on.  

If you decide to work a little longer on this problem, allow no more than an extra minute, two maximum, before you move on.  If you decide you must move on, skip directly to Step 5.

Step 2: Remind Yourself of the Goal

Remember: you are not actually supposed to solve the problem. You are solving only to see if you could arrive at a response when given each statement.  Imagine that you are a CEO and have employees to solve these problems for you.  Your only objective is to find out if, given this information, your employees could arrive at an answer. Or do they need further information? After all, as CEO, you do not want to be wasting your employees’ time!

Step 3: Search for a Shortcut

The GMAT rewards test-takers who can quickly find shortcuts.  After all, scoring system on the GMAT is trying to sort for great problem solvers.  It is part of the reason MBA programs put value in the score you earn. If you are stuck, take a moment to re-read the question-- perhaps there is something you missed that could turn into a nifty shortcut!

Step 4: Plug and Chug

If you can’t find a shortcut, and you still don’t know how you might solve the problem, try plugging in values to see if you will arrive at only one answer choice or several.  Remember, if the one or both statements do not point to a single answer, the statements are insufficient.  Try plugging in negative numbers, fractions, and zero-- but be careful to pick numbers that do not complicate the math. For more tips on backsolving, check out this post.

Step 5: Eliminate Answer Choices… and Guess

Almost every company that specializes in GMAT preparation has a different strategy for helping you eliminate answer choices and make an educated guess.  This is because knowing when and how to use this strategy could save you the precious minutes you will need later in the exam.

I prefer 12-TEN, which stands for:

1:   (A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.

2: (B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.

T: (C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

E: (D) EACH statement ALONE is sufficient. (EITHER)

N: (E) Statements (1) and (2) TOGETHER are NOT sufficient. (NEITHER)

I recommend jotting down 12-TEN on your scratch pad and crossing out the letters as you eliminate answer choices.  It helps you keep track of where you are in solving the problem.  Knowing what choices you can eliminate once you have determined if one statement is sufficient can allow you to guess an answer if you are short on time or cannot solve the problem.  For example, if you can prove that Statement (1) alone is sufficient, you know that the answer cannot be B, C, or E.  So, your choices are only A and D once you have proved that Statement (1) is sufficient.  Your chances of answering this question correctly have jumped significantly!

Cambridge Coaching GMAT tutors can help you find a strategy that’s right for you.  

Practice, Practice, Practice

Of course, simply reading this post will not help you on test day!  Make sure to keep this process in mind when solving practice problems.  When you solve batches of GMAT Data Sufficiency questions, time yourself, not just per question, but on the total time elapsed.  This will mimic test conditions more closely and will allow you to practice making the decision of whether or not to invest the time in the question or to simply make an educated guess and move onto the next question.

For more relevant reading, check out these other blog posts, written by our GRE tutors: X, Y, Z. Looking to work with Maryam Amr? Feel free to get in touch! Cambridge Coaching offers private in-person tutoring in New York City and Boston, and online tutoring around the world.

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