OG DS 117

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OG DS 117

by jzw » Tue Mar 06, 2012 11:54 am
So I messed up here but only because I thought that the smaller circle extends beyond the center of the larger circle. I know that in DS I cannot trust the picture given, but how was I supposed to know that the center of the big circle is the "end" of the diameter of the smaller circle? What in the text said this that I missed?

SORRY - just realized I forgot to upload the picture. See below.
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by jzw » Tue Mar 06, 2012 7:51 pm
Anyone know?

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by GMATGuruNY » Tue Mar 06, 2012 8:35 pm
Image

The area inside the larger circle but outside the smaller circle = larger circle - smaller circle.

Question rephrased: What is the area of each circle?

Statement 1: AB=3 and BC=2.
Image
Radius of the smaller circle = AB = 3.
Radius of the larger circle = AC = 3+2 = 5.
Thus, we can determine the area of each circle.
SUFFICIENT.

Statement 2: CD=1 and DE=4.
Image
Radius of the larger circle = CE = 1+4 = 5.
Since C is the center of the larger circle, AC = CE = 5.
Thus, the diameter of the smaller circle = AC+CD = 5+1 = 6.
Thus, we can determine the area of each circle.
SUFFICIENT.

The correct answer is D.
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