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## Introduction to the GMAT Computer-Adaptive Test

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One of the most challenging aspects of the GMAT is that it is an adaptive test. Not everyone sees the same questions, and you're not scored purely on how many questions you get right or wrong. This raises some complicated issues of preparation, timing, and strategy.

In short, the more questions you answer correctly, the tougher the test will become. The fewer questions you answer correctly, the easier the test will become. Rather than your typical test, which seeks to rate you on how many questions you can get right, the GMAT seeks to pinpoint your ability level. If you consistently get "680-level" questions wrong and consistently get "640-level" questions right, your score will fall somewhere between those points.

Based on thousands of tests, each item in the GMAT question pool is ranked. If, say, only 10% of test takers get that question right, it's a 90th percentile question, or a 680-level question. Everyone starts with a few questions at the 50th percentile level, and your performance on those dictates where you go from there.

The biggest adjustment you'll have to make is mental. It is likely that you will not answer every question correctly. You'll probably see several that are too difficult for you. You'll also see a few that look doable, but would take too much time to work through.

Realize, first, that in order to get a good score (even a great one, well above the 90th percentile), you don't need to get every question right. If you're forced to decide between having a chance at getting a question right and conserving time in order to ensure that you finish the test, finishing the test is far and away the better choice.

Second, learn to recognize questions that are beyond your skill level. When practicing, by all means try to learn how to do those questions. But if you hit a point where you know you'll never get tricky probability questions in less than 3:30, be ready to cut your losses on test day. Because the stakes of the GMAT are so high, we all want to nail every question and give our best effort. But if our best effort takes five minutes, the trade-off just isn't worth it. Keep that in mind while you work through difficult problem sets.

When Do the Questions Get Hard?

I hear this question all the time. Unfortunately, there's no simple answer. If you get the first five questions right, odds are question #6 will be difficult for you (especially on the Quantitative). If you get the first ten, #11 will be a killer. No generalization I can make, though, will apply to every single test.

Remember that no two GMAT test takers are identical. If a question is considered to be "700-level," that's only an average. If you're very good at geometry problems, you may cruise through 750-level geometry problems and struggle with 650-level algebra. You won't notice every subtlety of the test adapting to you, because you're not an "average" test taker--not even an average test-taker at your particular score level.

How Bad is it to Not Finish?

Really bad. A big part of the GMAT--by design--is time management. The testmakers want to see if you can budget your time effectively while you have so much else to think about. The main way they take that into account is by assessing a penalty for not finishing a section. They don't make public the amount of the penalty, but it's a safe bet that it's at least 30-50 points per section.

Worst case scenario, quickly guess on the last few questions to make sure you finish each section. However, in the last year or so, the GMAT has started to penalize you for rapidly moving through the final several questions. So, now more than ever, proper time management is key.

Depending on whom you ask, 10-25% of the questions on the GMAT are experimental. In other words, they don't count toward your score; they are used only for research purposes. Those questions may or may not be at your skill level.

This is yet another area in which mental preparedness is the most important thing. If you think you're doing great, then you suddenly see a very easy question, the natural reaction is to imagine you've missed a few questions in a row, and that the test has adjusted accordingly. However, that easy question could be experimental. For that matter, it could be one that you're just well prepared for.

General Thoughts

The key concept to take away (beyond the basic characteristics of the test) is that there are all sorts of reasons why the test won't feel perfectly adaptive to you. Most of the time, you won't recognize the test getting a little harder or easier. Since you're not an "average" test taker, and several of the questions are random (experimental), it's only natural. Don't let yourself obsess over details like that during the test.

It's important to know how the test works, but all this knowledge doesn't do you a whole lot of good during the test. It's very easy to think too much about how well you're doing, but that'll never be to your benefit. All you can do is manage your time well and get as many questions right as possible.

About the author: Jeff Sackmann has written many GMAT preparation books, including the popular Total GMAT Math, Total GMAT Verbal, and GMAT 111. He has also created explanations for problems in The Official Guide, as well as 1,800 practice GMAT math questions.

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