GMAT Problem Solving (PS) | Re: One side length of a left square is m and one side length of a right s

Based on the diagram- m^2 < n^2. Hence eliminate option B.
In all the other options the dimensions are not correct- meaning- area has to be of the form (length)^2. None of the other options are of that form (you can't do m + n^2 or n + m^2, it's like adding 1 metre and 1 sq.metre)

Hence answer has to be Option A.

Using this method you can solve this in 20 seconds max.

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