Geometry!

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Source: — Data Sufficiency |

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by prindaroy » Fri Jul 24, 2009 3:52 pm
BC/AB = 3/4

BC = (3/4)AB = (3/4)AD

1) Statement 1 alone is insufficient

2) Statement 2 alone in insufficient

Together, (3/4 CD)^2 + (CD)^2 = 625

Solve for CD, and you get CD = 20. So 25^2 - 20^2 = 225. sqrt(225) = 15

15 in the diameter and 7.5 the radius. And the answer to the question is C.

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by shibal » Fri Jul 24, 2009 5:40 pm
IMO B
stmt 2 gives us the diagonal line of the rectangle forming two 45-45-90 triangles. we can get then the BC measure, divide it by 2 and get the circle's area....

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by fruti_yum » Sun Aug 02, 2009 7:06 am
shibal wrote:IMO B
stmt 2 gives us the diagonal line of the rectangle forming two 45-45-90 triangles. we can get then the BC measure, divide it by 2 and get the circle's area....
i AGREE with Shibal!

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by fruti_yum » Sun Aug 02, 2009 7:06 am
shibal wrote:IMO B
stmt 2 gives us the diagonal line of the rectangle forming two 45-45-90 triangles. we can get then the BC measure, divide it by 2 and get the circle's area....
I agree with shibal

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by zeenab » Mon Aug 03, 2009 2:49 pm
Hi
I dont think, it is B,

How do we know the angles are 45-45-90?I think only in a square where the adjacent sides are equal the angles are 45-45-90. In a rectangle it can be anything.

I think C is correct.

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by tom4lax » Mon Aug 03, 2009 6:14 pm
Another vote for C. You can't tell the angle of the quad, it could be either a square or a rectangle