Analysis of Most Difficult Questions and CategoriesWe have collected 400 of the hardest questions discussed on GMAT Club (you can find the list of 100 of them here: Hardest GMAT Questions).
While collecting them, we have looked at the tags and categories to see if we can spot some patterns or make any conclusions - this post is about what we have learned.
Observation #1: Quant questions in the OG are not Representative
20% of the hardest PS questions and 40%!!! of the DS questions were from GMAT Prep and only 13% and 9% respectfully were from the Official Guide. That tells me that GMAT Prep is pretty tricky and continues to surprise test takers while the Official Guide is not as representative of the difficult questions you are to encounter on the GMAT
Observation #2: Arithmetic is harder and more important than Probability
15% of the 100 hardest PS questions were arithmetic and 31% of DS were inequalities, ahead of combinations, which were 9% in PS. Did you know that around 50% of the questions you encounter on the GMAT will be arithmetic questions? If you are short on time and choosing whether to spend the next 3 days in probability or in arithmetic, choose arithmetic.
Observation #3: Parallel Structure is a challenge in SC
SC is the most common question type on the Verbal portion of the test and most issues come up with Parallel Structure, Modifiers, and Subject Verb agreement - make sure you ace these 3 topics before your appointment.
Observation #4: Verbal questions in the OG are Representative!
For Verbal, the difference between OG and GMAT Prep is not as significant as in the quant, which indicates that OG is a pretty good source for your verbal practice and it is very representative of the GMAT. (Here of course we had to make an assumption that GMAT Prep is representative of the actual GMAT, which I hope you caught since Assumptions are the most problematic area in CR). Anyway, you want to value and savor those Verbal questions as no other source has them as good, as hard, and as original.
Top 10 Hardest Question Areas by Question Type
(click to see the questions related to each topic/tag). Freq = Frequency of the tag/category in the top 100
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