Why You Felt Good on the GMAT Quant Section but Didn’t Score Well

This is a problem that I have seen many times before. It leaves students bewildered because all of the signs that would lead them to expect a lower score are absent. They did not run out of time, they did not have to guess at lots of questions, and they did not feel overwhelmed. Even I have suffered from this a bit, my lowest Quant score came on the exam where I felt most comfortable – and my highest score on Quant came on the exam that felt the worst.

How is it that you can confidentially answer question after question while obviously missing quite a few questions that felt “easy?”

One culprit is the subtlety of the official GMAT questions overall. No other questions do as good a job of luring you into confidently choosing the wrong answer. This can happen on problem solving, but today I would like to focus on Data Sufficiency.

I sometimes refer to Data Sufficiency as “the Silent Killer” because the very structure of the Data Sufficiency question invites you to choose the wrong answer. This is because you do not know that you have forgotten to consider something. There are no values in the answer choices to help you see what you might have overlooked. That is why the person choosing the incorrect answer is often more confident than is the one who got the question right.

As you can see it is often difficult to gauge how you are doing on Data Sufficiency. And because the Quantitative section adapts as a whole, missing these data sufficiency questions results in the computer selecting lower-level questions in problem solving. So the problem solving questions may have seemed easier because they actually were at a lower level.

This is a pattern that I have seen repeated many times on practice exams. Students miss mid-level data sufficiency questions in the first part of the exam. This results in lower level questions being offered, and the student keeps missing just enough problems (of both Data Sufficiency and Problem Solving) to keep the difficulty level from increasing.

The result? A quant section that felt comfortable because most of the questions were below the level that would really challenge the student. This may be what happened to you.

How to avoid this fate:

With Data Sufficiency questions there are no answer choices to provide a check on your assumptions or calculations. You must be your own editor and look for mistakes before you confirm your answer. Fortunately, there are several things you can do:

  1. Think with your pen. Do not presume that you will remember what the question is asking, the facts you are given, or the hidden facts that are implied by the question stem. Note these things on your scratch paper so that you do not forget them. It may seem unnecessary to write “x is integer” or “must be positive” but just think of how dangerous it would be to forget this information!

  1. Do your work early. Rewording the question is a great way to make data sufficiency more fool-proof. For example, it is much easier to comprehend the question “Is x a multiple of 4” than it is to wrestle with the questions “Is x/2 a multiple of 2?” Think about what the question is really asking and re-word it when you can.

  1. Catch mistakes before you submit. Always keep in mind the most common number properties, “positive/ negative” “integer/ non-integer” and “the numbers 0 and 1.” The test makers can really hide these number properties so that even experts could overlook them, so just run through these three number properties on every problem and you will catch lots of your mistakes before you submit.

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David Newland has been teaching for Veritas Prep since 2006, and he won the Veritas Prep Instructor of the Year award in 2008. Students’ friends often call in asking when he will be teaching next because he really is a Veritas Prep and a GMAT rock star! Read more of his articles here.