A metal sheet 27 cm long 8cm broad and 1 cm thick is melted into a cube. The difference between the surface areas of two solids is__________?

A. 284 cm2
B. 286 cm2
C. 296 cm2
D. 300 cm2
Explanation:
Volume of sheet = (27 × 8 × 1)cm3 = 216 cm3

Volume of cube formed = 216 cm3

Therefore, Edge of the cube = (6 × 6 × 6)1/3 = 6 cm

Surface area of original cuboid = 2 (27 × 8 + 8 × 1 + 27 × 1) cm2 = 502 cm2

Surface area of the cube formed = [6 × (6) 2] cm2 = 216 cm2

Therefore, Difference in areas = (502 – 216)cm2= 286 cm2