Are most of these IR questions designed to be just brute force plugging and chugging numbers?
Not at all. First of all, I would recommend the Magoosh
IR eBook, to see the astonishing variety possible among IR questions. http://magoosh.com/gmat/2012/gmat-integ ... ing-ebook/
As you will see in that eBook there are four IR question types
(a) Multi-Source Reasoning (MSR)
(b) Table Analysis (TA)
(c) Graphic Interpretation (GI)
(d) Two-Part Analysis (2PA)
You will see all four types on any live GMAT IR section. This, of course, is a 2PA question.
Of these four question types, the only ones that could deal with something intensely numerical like a recursive sequence are the 2PA questions--- this current question is not at all representative of a MSR, a TA, or a GI question.
Furthermore, the 2PA is easily the most versatile question format on the entire GMAT
. Some 2PA questions, like this, are purely numerical --- they can involve sequence or any one of a number of other number property topics; other 2PA questions are algebraic & symbolic, similar to PS questions that involve variables in the answer choices; other 2PA questions can involve reading a chart or graph, and these share skills in common with GI questions; other 2PA questions are purely verbal, and involve the skills you will also use in RC and CR questions.
This blog gives an example of an algebraic 2PAhttp://magoosh.com/gmat/2012/integrated ... -analysis/
This blog gives you the relative breakdown of question types and their sub-formats in the 50 IR questions of GMAC's official IR website (you get full access to this website with the purchase of the OG13.) This includes a breakdown of the different kinds of 2PA questions. http://magoosh.com/gmat/2012/gmacs-offi ... -new-gmat/
The question I posted in this thread is representative of one particular genre of numerical 2PA question --- that is representative of only one subset of only one kind of only one of the four questions on the IR. Yes, it is representative of a particular question format that could appear on the GMAT, but NOT AT ALL representative of the IR section overall.
Does all that make sense? Please let me know if you have any more IR-related questions.
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