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 Andrew Mitchell, director of pre-business programs and GMAT instructor at Kaplan Test Prep.
One of the two question types on the quantitative section of the GMAT is data sufficiency. It’s a question type unique to the GMAT; no other standardized test contains a question type of this format. Within data sufficiency, there are two different sub-types, which can be classified as “value” and “yes/no.” A value question will simply ask for a value: “What is the value of x?” or “How much money did Jill make in 2011?” A yes/no question is a little more nuanced: It will ask a question such as “is a positive?” or “Did Jill make more than John in 2011?” For all data-sufficiency questions, consider what information you would need to answer the question before looking at the additional data provided in the statements.
Here’s an example of understanding what to look for in a yes/no question:
“In Triangle ABC, side AB has a length of 2, and side BC has a length of 5.”
Knowledge of the Triangle Inequality Theorem will be extremely helpful here—the GMAT will require some level of content mastery. Fortunately, this is a relatively easy concept to master: For three sides of a triangle, the length of any one side must be both greater than the difference of the lengths of the other two sides and less than the sum of the lengths of the other two sides.
A data-sufficiency question could ask something about the length of side AC. There’s no way to know the exact value of the length of side AC.
In understanding the concept of yes/no, consider the following question:
“Is the length of side AC greater than 8?”
Using the Triangle Inequality Theorem, you know that the length of side AC must be greater than 3 and less than 7. Without any further knowledge of the triangle, you’re able to definitively answer this question with a no. You may have been tempted to think you need further information: Is the triangle a right triangle or isosceles? What are the angle measurements of the triangle? But you don’t need any further information. Maintain the same mindset for yes/no questions in data sufficiency; think about what information is needed, rather than trying to drill down to a specific answer. Yes/no questions don’t require a specific-value answer and often won’t even allow one.
But you’ve answered the question being asked, and that’s another step toward GMAT success.
Mitchell helps manage Kaplan Test Prep’s GMAT business, including marketing, program development, and delivery. Still an active GMAT and GRE instructor, Mitchell is leading Kaplan’s efforts to revamp its curriculum to teach the GMAT’s new Integrated Reasoning section. A best-selling author, his previous experience includes consulting for the Pentagon and product development at Google. Mitchell graduated from Harvard University with a B.S. in physics in 2001 and completed his MBA in 2007 at the University of Chicago’s Booth School of Business.