Q2 of 227 Page 914

The volume of a cube is 729 cm3. Find its surface area.

Given,


Volume of the cube = 729 cm3


Let the edge of the cube = a cm


So,


Volume (v) of the cube = a3
a3 = 729
a3 = (9cm)3
a = 9 cm


Lateral surface area of cube = 4a2
= 4 × 92
= 4 × 81
= 324cm2
Total surface area of the cube = 6a2
= 6 × 92
= 6 × 81
= 486 cm2


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