Question -
A metal sheet 27 cm long, 8 cm broad and 1 cm thick is melted into a cube. The difference between total surface area of the two solids is ______ cm2.
Options:
A .  280 cm2
B .  284 cm2
C .  286 cm2
D .  296 cm2
Answer: Option C : C The metal sheet is in the shape of a cuboid. Total surface area of the cuboid is given by2 (lb + bh + hl) = 2[(27 ×8) + (8 ×1) + (1 ×27)] = 502 cm2. When themetal sheet is melted into a cube, then the volume of themetal sheet will be equal to the volume of thecube. Hence, Volume of the cuboid = Volume of the cube Let eachside of thecube be a Hence, 27 × 8 × 1 = a3 ⇒a = 6 cm Total Surface area of the cube is given by6a2 = 6 × (6)2 = 216 cm2. Hence, the difference between surface areas of two solids = (502 -216)cm2 = 286 cm2.
Submit Your Solution hear: