Question

The perimeter of one face of a cube is $40$ $cm$ . Find the sum of the length of its edges .

Answer 1

Let length of one edge of the cube is $a$

Perimeter of one face of a cube is $40$ $cm$

$\Rightarrow 4a=40$
$\Rightarrow a=\frac{40}{4}$
$\Rightarrow a=10$ cm

length of one edge$=10$ $cm$

no of edge in a cube$=12$

sum of length of all the edges of cube$=12\times 10$cm $=120$cm.