PacingAlthough time is limited on the GMAT, working too quickly can damage your score. Many problems hinge on subtle points, and most require careful reading of the setup. Because undergraduate school puts such heavy reading loads on students, many will follow their academic conditioning and read the questions quickly, looking only for the gist of what the question is asking. Once they have found it, they mark their answer and move on, confident they have answered it correctly. Later, many are startled to discover that they missed questions because they either misread the problems or overlooked subtle points.
To do well in your undergraduate classes, you had to attempt to solve every, or nearly every, problem on a test. Not so with the GMAT. For the vast majority of people, the key to performing well on the GMAT is not the number of questions they solve, within reason, but the percentage they solve correctly.