I must strenuously disagree with all of these posts! I won't argue about whether our quant sections are harder--some people find them so, although others find that they are unable to match their practice scores on the real test. In any case, that's not the problem here.
The problem is that it is absolutely essential to treat practice tests as *practice tests.* You should never give yourself extra time, nor should you allow yourself to run out of time at the end, or guess on the last 5-7 questions. The GMAT is a timed test, and handling the time constraints is an essential skill for anyone looking to break 600, let alone 700. If a problem is too difficult or time-consuming, move on. Don't spend 4 minutes on a problem, don't press the pause button, and don't give yourself any luxuries you won't have on the real test. Our tests allow you to set the time, and this is great for those who have been granted extended time on the test. If that's not you, you should complete each section in 75 minutes each time--no more, and preferably not much less. Remember that even at the 700 level, you will miss about 40% of the problems. Don't get hung up! Keep moving, and if you find you've moved *too* fast, adjust your pacing for the next test.
For those wanting to get the most out of the test, don't worry! You can always go back and review, taking as much time as you need to really understand the problem. In fact, I recommend that you review each problem this way before you even check the answers. This forces you to think harder, make connections, and look for alternate ways of seeing the problem. This is much healthier for your performance than simply checking the answers and reading the explanations.
Good luck!
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