Three cubes of sides 1 cm, 6 cm and 8 cm are melted to form a new cube. Find one-fourth of the surface area of the new cube.
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e 121.5 cm2
Volumes of the cubes = 1³ = 1; 6³ = 216 and 8³ = 512
Total volume = 1 + 216 + 512 = 729 cubic cm
Cube root of 729 = 9 cm
Surface area of new cube = 6 × 9 × 9 = 486 square cm
One-fourth of surface area = 486 ÷ 4 = 121.5 square cm