Area of circle

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Area of circle

by Ashetty » Sat Jul 16, 2011 9:31 am
The diameter of circle S is equal in length to a certain square. The diameter od circle T is equal in length to a diagnol of the same square. The area of circle T is how many times the area of circle S?
Ans is 2.
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by MBA.Aspirant » Sat Jul 16, 2011 9:54 am
Ashetty wrote:The diameter of circle S is equal in length to a certain square. The diameter od circle T is equal in length to a diagnol of the same square. The area of circle T is how many times the area of circle S?
Ans is 2.

let square side = s

diagonal of square = √2 s

or

√s^2+s^2 = √2 s


area of circle S = TT (s/2)^2 = TT s^2/4

area of circle T = TT (√2 s/2)^2 = TT 2s^2/4 = TT s^2/2

T:S

TT s^2/2 : TT s^2/4 (x4, remove TT and s^2)

2 : 1