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Source: — Data Sufficiency |

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by Night reader » Mon Jan 10, 2011 5:01 pm
GHong14 wrote:Image
Let us call sides of square x and the two sides of rectangle y and z, then 4x=2*(y+z); find (y*z)/(x^2)
given y/z=2/3 OR y=2z/3

solution: simplifying => 2x=y+z <=> 2x=2z/3 + z <=> 2x=5z/3 OR x=5z/6
x^2=(5z/6)^2
y*z=(2z/3)*z= 2z^2/3

(y*z)/(x^2)= (2z^2)/3 : (25z^2)/36 = 24/25

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by anshumishra » Mon Jan 10, 2011 7:58 pm
GHong14 wrote:Image
Night reader's method is perfect.

Here is another (PIN) approach :
side of rectangle, x = 2, y =3 , area of rectangle = 6
=> side of square = (4+6)/4 = 5/2 , area of square =25/4

So, the required ratio = 6/(25/4) = 24:25.
Thanks
Anshu

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