Question

The total surface area of a cube is $9.6{cm}^2$ , then what is its volume,

Answer 1

Total surface area of a cube with side $a$ units $=6a^2$ sq.units

i.e., $6a^2=9.6$

$⟹a^2=\frac{9.6}{6}=1.6=\frac{(4{)}^2}{10}$

$\therefore a=\frac{4}{\sqrt{10}}$ cm.

Volume of a cube with side $a$ units $=a^3$ cu.units

Volume $=(\frac{4}{\sqrt{10}}{)}^3=\frac{64}{10\sqrt{10}}=\frac{64\sqrt{10}}{100}c{m}^3$