Question

If the perimeter of one face of a cube is $20cm$, then its surface area is

• A. $120c{m}^2$
• B. $150c{m}^2$
• C. $125c{m}^2$
• D. $400c{m}^2$

Answer 1

Answer: (B)

$150c{m}^2$

Perimeter of one face of a cube is $4a=20$

$\Rightarrow a=5$ $cm$
Now the surface area will be $6a^2$

$=6\times 5\times 5$
$=150c{m}^2$
Hence, option $B$ is correct.