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by bluementor » Thu May 07, 2009 3:34 am
a = area of circle A
b = area of circle B
c = area of circle inscribed inside square WXYZ

each side of the WXYZ square = w, so area of WXYZ square = w^2

the question gives us the following relationships:
a = 3b
b = w^2/6

so, a = 3(w^2/6) = (w^2)/2

the circle inscribed within WXYZ will have a diameter equal to the length of each side of WXYZ. So,

c = pi*(w/2)^2

we can now calclulate the ratio:

c/a = (pi*(w^2)/4) / (w^2)/2
c/a = pi/2

Choose C.

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Re: problem

by sanju09 » Thu May 07, 2009 3:55 am
hmboy17 wrote:help needed
Area Circle A = 3 b (let’s say), where b is the area of Circle B.

And b = (1/6) x^2, or x^2 = 6 b; where x is each side of square WXYZ. Hence radius of circle that can be inscribed within the square WXYZ, will be x/2, and its area will be π (x^2/4) = π (6 b)/4 = (3/2) b π. The required ratio is (3/2) b π : 3 b = π/2.

Go with C.
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