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#GRE practicequestion The figure above is made up of 4 squares.jpg

This becomes a triangle which has the angles in the ratio of \(45:45:90\) or \(x:x:x\sqrt{2}\)

We do know this because the segment AB is \(8\sqrt{2}\)

which means that the other sides are 8

One side of a square is 4.

We want to know the perimeter of the shaded region which has 10 sides

\(4 \times 10 = 40\)

C is the answer

Aren't we supposed to be told that all the squares are equal? By assuming that they are equal, we might be missing a case when they aren't.