A unit square is circumscribed about a circle...

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A unit square is circumscribed about a circle. If the circumference of the circle is qπ, what is the value of q?

(A) 1
(B) 2
(C) π
(D) 2Ï€
(E) 5Ï€

The OA is A.

I don't understand this PS question. Please can any expert assist me with it? Thanks.

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by dabral » Mon Oct 30, 2017 11:07 pm
Hi swerve,

First off this is not an official GMAT question because it assumes that you know that a unit square has a side of unit 1. The GMAT does not require one to have prior knowledge of jargon, and that is why I always recommend students to stick with official GMAT questions.

As for this particular question the key idea to know that when a circle is circumscribed by a square then the diameter of the circle is equal to the side of the square. You should try to draw this out and this connection will make sense. If the diameter of the circle is 1, then its circumference is equal to pi times diameter or in this case pi, and this is what makes q=1. I hope this makes sense.

Cheers,
Dabral
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