gmat prep question

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by manulath » Sun Sep 28, 2008 11:41 pm
one was used to form a circle of radiur r
hence circumfrence = 2pi.r

let the two parts = x and y such that x + y = 40

let x be used to make circle.
Hence x = 2pi.r

y = 40 - 2pi.r

y formed a square. Perimeter of square = 4*side = 40 - 2pi*r
side = 10 - pi*r/2

Area: Circle = pi*r^2
Square = (10 - pi*r/2)^2

Sum of area = pi*r^2 + (10 - pi*r/2)^2