The metal sheet is in the shape of a cuboid.
Total surface area of the cuboid is given by 2 (lb + bh + hl) = 2[(27 ×8) + (8 ×1) + (1 ×27)] = 502 cm2.
When the metal sheet is melted into a cube, then the volume of the metal sheet will be equal to the volume of the cube.
Hence, Volume of the cuboid = Volume of the cube
Let each side of the cube be a
Hence, 27 × 8 × 1 = a3
⇒a = 6 cm
Total Surface area of the cube is given by 6a2 = 6 × (6)2 = 216 cm2.
Hence, the difference between surface areas of two solids = (502 -216) cm2 = 286 cm2.