Question

The edge of a cube is increased by 100%, the surface area of the cube is increased by:

• A. 100%
• B. 200%
• C. 300%
• D. 400%

Answer 1

The correct option is C 300%

Let edge of a smaller cube be 1 m
$\therefore$ Edge of larger cube = 2 m
and Surface area of smaller cube $=6\times (1{)}^2=6m^2$
$\therefore$ Surface area of larger cube $=6\times (2{)}^2=24m^2$
$\therefore$ % increase in surface area $=\frac{24-6}{6}\times 100=300\%$