(i) Let the edge of cube be l.
Since, Surface area of the cube (A)=6l²
When edge of cube is doubled, then
Surface area of the cube (A’)= 6(2l)² = 6x4l² = 4x6l²
A’ = 4 x A, Hence, the surface area will increase four times.
(ii) Volume of cube (V) = l³
When edge of cube is doubled, then volume of cube (V’)=(2l)³=8l³
V’ = 8 x V, Hence, the volume will increase 8 times.

Class 8 Maths Chapter 11 Exercise 11.4 Solution in Video

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