Gmat club tricky PS.

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Gmat club tricky PS.

by bblast » Sun May 08, 2011 5:59 am
A 4 cm cube is cut into 1 cm cubes. What is the percentage increase in the surface area after such cutting?

(A) 4%
(B) 166%
(C) 266%
(D) 300%
(E) 400%

OA-D

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by pankajks2010 » Sun May 08, 2011 9:36 am
The volume of 4cm cube is 64 cubic cm and the volume of 1 cm cube is 1 cubic cm. Thus, there would be 64, one cm cubes out of the bigger (4 cm cube).

Now, surface area of 4cm cube is 96 sq. cm. The surface area of 1cm cube is 6 sq. cm. Thus, the total surface area of 64 cubes = 64*6=384 sq cm.

Now, percentage increase = ((384/96)-1)*100=300%

Thus D