Kaplan Geometry Question

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by kmittal82 » Tue Aug 17, 2010 4:03 am
Hi,

I don't fully understand Q1 myself, but here is my attempt at Q2

Let radius of the circle = r
side of square = a

Question is asking, is pi*r^2 = a^2

(1)
Diameter = Side => 2r = a => r = a/2

Area of circle = pi*r^2 = pi*(a/2)^2 = pi*a^2/4

Area of square = a^2

Clearly, pi*a^2/4 is not equal to a^2 (if it was, we would pi = 4), hence sufficient to answer the question

(2)

(2/3)*pi*r^2 < (5/8)*a^2

=> 16*pi*r^2 < 15*a^2

If pi*r^2 = a^2, then we would get 16<15, which is not true, hence sufficient to answer the question as well.

Thus, in my opinion, answer should be (D). Can you please confirm the OA?

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by kvcpk » Tue Aug 17, 2010 4:24 am
first problem:

two points are given.

It means that a line segment is given.

With a line segment as a chord, any number of circles can be drawn.

Hence pick D.
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by gmatmachoman » Tue Aug 17, 2010 5:03 am
very nice questions :

1 : D

2: D