Management Aptitude Test Dec 2012 Paper

(c) Surface area of metal sheet
= 2 (27 x 8 + 8 x 1 + 1 x 27)
= 2(216 + 8 + 27)
= 2 x 251 = 502 $\mathit{c}{\mathit{m}}^2$
Let edge of cube which we form be x. Then,
according to the question,
${\mathit{x}}^3$ = 27 x 8 x 1
⇒ x = 3 x 2 = 6cm
∴ Surface area of the cube = 6 ${\mathit{x}}^2$
= 6 x $6^2$ = 216 $\mathit{c}{\mathit{m}}^2$
∴ Required difference = 502 - 216 = 286 $\mathit{c}{\mathit{m}}^2$