Question

If the lateral surface area of a cube is $1600c{m}^2$, then its edge is

• A. $15cm$
• B. $18cm$
• C. $20cm$
• D. $25cm$

Answer 1

The correct option is C $20cm$

Let the edge of the cube be $a$ cm.

Lateral surface area of cube $=4a^2$

$\therefore 4a^2=1600$

$\Rightarrow a^2=400$

$\Rightarrow a=\sqrt{400}$

$\Rightarrow a=20$

Hence, the edge of the cube is $20cm$