Question on geometry

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Question on geometry

by [email protected] » Thu Oct 20, 2016 6:06 am
Would be obliged if you could explain highlighted paragraph and the solution of the following problem. I have attached both the question and the answer. Thank you.


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by [email protected] » Thu Oct 20, 2016 10:18 am
Hi sucheta.lahiri,

This is an example of a Quantitative Comparison question from the GRE, so it's out-of-place here on a GMAT website. You might be better served by seeking out GRE-specific websites to ask your questions.

That having been said, the concept involved is a rarer mathematical concept that has to do with how the products of numbers behave. For example, watch what happens as two numbers get closer and closer together:

(1)(9) = 9
(2)(8) = 16
(3)(7) = 21
(4)(6) = 24
(5)(5) = 25

If the two numbers increase/decrease by the same amount, then the product gets bigger (and it's biggest when the two numbers are equal). The same principal applies in this QC question (and to rectangles and squares in general).

GMAT assassins aren't born, they're made,
Rich
Contact Rich at [email protected]
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