Question

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

• A. \(284\ cm ^ 2\)
• B. \(296\ cm ^ 2\)
• C. \(286\ cm ^ 2\)
• D. \(300\ cm ^ 2\)

Answer 1

The Correct Option is C

Surface area of the metal sheet = 2(lb + bh + hl)
= 2(27 x 8 + 8 x 1 + 1 x 27)
= 2(216 + 8 + 27)
= 2(251) = 502 cm²
Edge of the cube which is formed after melting = l x b x h
i.e a³ = 27 x 8 x 1 (or) a = 6
Surface area of the cube = 6a² = 216
Required difference = 502 - 216 = 286 cm²
Hence, option C is the correct answer.The correct option is (C): 286 cm ^ 2