Question

Total surface area of a cube is 864 sq.cm. Find its volume.

Answer 1

Given: Total surface area of cube = 864 sq. cm 

To find: Volume of cube 

Solution:

i. Total surface area of cube = 6l² 

∴ 864 = 6l² 

∴ l² = \(\sqrt[864]6\)

∴ l² = 144

∴ l = \(\sqrt{144}\)… [Taking square root on both sides] 

= 12 cm 

ii. Volume of cube = l²

 = 12³

= 1728 cubic cm. 

∴ The volume of cube is 1728 cubic cm.