The biggest mistake almost everyone makes on the GMAT

Up until now, most if not all of the tests you have taken have based the score you received on the amount of questions you answered correctly. To ace tests, you were taught to use all the allotted time to double check your answers, trying your hardest to answer each question correctly and achieve the coveted 100 percent or A+.

Yet if you approach the GMAT with this goal, you’ll set yourself up for a host of score-killing dilemmas. Your GMAT score isn’t based on how many questions you get right. In fact, the top scorers don’t expect to get every question right and plan to take guesses. In order to understand why such a strategy helps them maximize their score, it helps to understand a little bit about how the GMAT functions.

Scores, question difficulty and the GMAT algorithm

Rather than base your score on the percent of questions answered correctly, the GMAT calculates your score according to the difficulty level of the questions you get right and wrong. This is the function of the much talked about GMAT algorithm.

The algorithm is complex, and its exact construction is a closely guarded secret of GMAC, but you can think of it as a sort of choose-your-own-adventure book (grant it, one that no one would want to read). Instead of answering a standard set of questions, each test taker’s path through the test is unique. Test takers don’t answer the same questions. Instead, the algorithm selects each question it gives you based on the difficultly of the previous questions you answered and whether you answered them correctly.

The point of this process is to find the difficulty level at which you answer roughly 60 percent of the questions correctly. If you get a few questions right, the algorithm will select harder questions. If you get a few questions wrong, the algorithm will select easier questions. The test then generates your score based on the difficulty of the questions you answered correctly and incorrectly.

This test design leads to a few interesting features: Missing easier questions hurts your score more than missing hard questions, and all test-takers, even those who score in the highest GMAT percentiles, are guaranteed to miss a significant number of questions.

The GMAT is designed so that even these top test takers will encounter questions that are just too hard for them to answer in the allotted time, and yet these questions don’t hurt their score as much as you may think because the overall difficulty of the questions they answer is high. Test takers who score low on the GMAT, on the other hand, generally miss many easy questions. Because of this the general difficulty level of their “60 percent” range is low.