Gmat Prep (Geometry and fractions)

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Gmat Prep (Geometry and fractions)

by aosh » Wed Aug 01, 2007 5:11 am
I did the usual trick of calculating both circular areas and subtract, but that did not help!

A circular cloth with a diameter of 20 inches is placed on a circular tray with a diameter of 24 inches. What fraction of the tray’s surface is NOT covered by the cloth?

- 1/6
- 1/5
- 11/36
- 25/36
- 5/6

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by lanter1 » Wed Aug 01, 2007 5:36 am
Not covered is (1-covered)

(1-(10^2Pi/12^2Pi)=44/144=11/36