Question

Three cubes, whose edges are x cm, 8 cm, and 10 cm respectively, are melted and recast into a single cube of edge 12 cm. Find 'x'.

Answer 1

Volume of melted single cube x³ + 8³ + 10³ cm³

= x³ + 512 + 1000 cm³
= x³ + 1512 cm³

Given that 12 cm is edge of the single cube.

12³ = x³ + 1512 cm³
x³ = 12³ - 1512 cm³
x³ = 1728 - 1512
x³  = 216
x³ = 6³
x = 6 cm