Received a PM asking me to reply.
You said that your quant section was "overtime 15 mins" - do you mean you set the timer for longer than is allowed on the real test?
If so, your test results are not valid. Extra time can make a HUGE difference to your score for a variety of reasons - so that test was not representative of how you would do on the real test.
It's important to take practice tests under official conditions, including timing, the essays, the length of the breaks - everything. That's the only way to get practice results that are as valid as possible (though still not as valid as taking the real test!).
In terms of frequency, I tell my students to take practice tests only once every 2-3 weeks until a few weeks before the test, when they can start to take the tests once a week.
Why? Well, CAT exams are really good for (a) figuring out where you're scoring right now, (b) practicing stamina, and (c) analyzing your strengths and weaknesses. The actual act of just taking the exam is NOT so useful for improving. It's what you do with the test results / between tests that helps you to improve.
I would recommend, however, that you take another practice test soon under strict official conditions (if you didn't last time), so that you know you are working off of valid data. If you take a GMATPrep test, you will get the most valid result (because that's coming from the people who make the real test), but you won't get all of the data about strengths and weaknesses. So, for now, I would recommend taking a practice test from a test prep company so that you can get that data - and save the GMATPrep tests for a bit later in your study.
Re: CR (or anything with which you are struggling!), the first thing to ask yourself is: why? Are you bad at ALL CR questions? Probably not. So, which ones are giving you trouble. WHY are they giving you trouble? Are you struggling to understand the argument? the question? the answers? all of the above?
If the argument - you need to study how to read and extract information from the argument. Break it down into parts: what's the conclusion? What are the premises? Are there any counter-premises? What is fact vs. what is claim / opinion? What is the author assuming, even though s/he doesn't say it? [For instance, if I tell you that the Grapefruit Diet is the best way to lose weight then I'm assuming there isn't a better weight loss plan out there, even things I've never tried or heard about!]
Re: the question itself: do you know the different kinds of CR questions that can be asked? Do you know how to recognize, from reading the question stem, the specific type of CR question being asked? Do you know what you are supposed to do for each different type?
Re: the answers: do you mostly understand the above stuff but tend to fall into traps on the answers? WHY did you think that wrong answer was right? Not just "why is this wrong" - but you picked it, so you actually thought it was right. Why? Then, ask yourself what the fault was in your thinking. By the same token, you eliminated the right answer - you actually thought it was wrong (or, at least, not as good as the one you picked). Why? And what was the fault in your thinking this time?
Finally, I very much second Eric's suggestion to use the forums. You can post specific questions to discuss all of the above with fellow students and experts.
Oh - and re: whether you scored well, it just depends on your goal! Do you have a goal score in mind? Have you taken a look at the average scores at the schools to which you plan to apply? For some schools, a 660 would be a great score, for some that would be an average score, and for still others that would be a lower score. It just depends on where you plan to apply!
Please note: I do not use the Private Messaging system! I will not see any PMs that you send to me!!
Stacey Koprince
GMAT Instructor
Director of Online Community
Manhattan GMAT
Contributor to Beat The GMAT!
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