The probability questions in OG are fairly easy ..
Could some one guide me if one should be doing tougher problems than those given in OG if you are tragetting 700+ or will OG suffice.
I am practising both 12th edition and 10th edition !
Thank you in advance.
It might be a good idea for you to check out the Veritas
Combinatorics and Probability book. It covers the GMAT relevant theory of these topics and provides you with many higher level questions.
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