Question

A metal cube of edge 12 cm is melted and formed into three smaller cubes. If the edges of the two smaller cubes are 6 cm and 8 cm, find the edge of the third smaller cube.

Answer 1

Volume of large cube `= V_1+V_2+V_3`
Let the edge of the third cube be x cm
`123^3 = 6^3+8^3+x^3`
`1728=216+512+x^3`

⇒`x^3=1728-728=1000`

⇒`x=10cm`

∴Side of third side= 10cm.