I want to focus on 6-700 level questions for certain categories of Q that I'm having difficutly with in that range. Is there a way to figure difficulty levels for OG questions, or is there a resource that produces questions by subject and difficulty level?

I don't know of a resource that would specifically give you questions only in that general range, no. As a general rule, as the numbers get higher in OG, the problems get harder.

But what I'd argue is this: you don't actually care what the artificial rating of the problem is. You care whether you can do the problem sitting in front of you right now, accurately and efficiently. Your skill level will vary depending on question type / content area.

So start going through OG. If problem 10 is way too easy, skip up to problem 30 or 40. Still too easy? Go higher. If you're using GMATPrep Prep Pack #1, maybe you only choose the medium and harder questions, not the easy ones. But there are still things to learn on easier problems too - we can often learn shortcuts, for example, on an easier problem that will then help us to move more quickly on harder problems of the same type. :)

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Stacey Koprince
Instructor
Director of Online Community
ManhattanGMAT