Some excellent discussion on this thread.
The
Manhattan CATs are about as representative as you can get without including questions from Official Guides (prohibited by copyright laws). We recently updated the grading scale to more accurately represent the score you might expect on the GMAT. The CATs are great to practice and benchmark your score, but remember that the most important aspect of the practice exams is to identify your areas of weakness so you can focus your precious study time.
A few cautions: don't become more comfortable with "practice" test questions than with actual "GMAT" test questions, understand that the GMAT is always evolving, and realize that no practice can fully represent the actual test.
People can get in trouble by becoming too comfortable with test questions from test-prep companies. These "practice" questions are invaluable for providing extra practice questions and teaching key GMAT concepts. However, if you don't spend adequate time working on GMAT questions (Official Guides, GMATPrep exams, GMAT Focus, etc.), you will find that these real GMAT questions seem a bit awkward or even harder than what you are used to. That can be a very uncomfortable feeling especially if it happens when are sitting down for the GMAT itself. Throughout your preparation, be sure to include plenty of
Official Guide practice (in timed sets of multiple problems). Save the GMATPrep exams for closer to test day but consider purchasing the Question Packs to get some additional practice early in your preparation.
Recognize that the GMAT is always evolving elements of its content. The tested concepts are generally static, but new questions are constantly being created and certain areas of emphasis change over time. The most significant change we've seen recently has been the increased emphasis on Meaning in Sentence Correction. Meaning problems must be practiced, but because this empahsis is relatively new there aren't many good sources of pracitce problems. Many
Official Guide problems are still full of idiom issues (which are being de-emphasized) and they lack any real meaning issues. Studying modifier questions and practicing "new" GMAT content (GMATPrep and Question Pack) are good ways to prepare yourself.
Lastly, the GMAT experience will be different than any of your prior practice exams. When you take the real GMAT you will be in a controlled test environment, you will be exposed to experimental questions, and you will be taking the REAL test! This means that your performance on the real test will not always track with your practice exams. You can't mimic the experimental question aspect of the GMAT, but you can make your practice environment as "test-like" as possible. Take your exams according to the timeline of the GMAT. Take all the timed breaks and don't take any extra. Take the exam in a single sitting with all the test parts. Take the exam at the same time of day as your real test (whenever possible). Report your scores to others to give yourself similar test "pressure". Perhaps most importantly, plan to take the exam multiple times, remembering the mandatory 31 day wait period between exams.
KW
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