# Find the volume of a sphere whose radius is

Question.

Find the volume of a sphere whose radius is

(i) $7 \mathrm{~cm}$

(ii) $0.63 \mathrm{~m}$

$\left[\right.$ Assume $\left.\pi=\frac{22}{7}\right]$

Solution:

(i) Radius of sphere $=7 \mathrm{~cm}$

Volume of sphere $=\frac{4}{3} \pi r^{3}$

$=\left[\frac{4}{3} \times \frac{22}{7} \times(7)^{3}\right] \mathrm{cm}^{3}$

$=\left(\frac{4312}{3}\right) \mathrm{cm}^{3}$

$=1437 \frac{1}{3} \mathrm{~cm}^{3}$

Therefore, the volume of the sphere is $1437 \frac{1}{3} \mathrm{~cm}^{3}$.

(ii) Radius of sphere $=0.63 \mathrm{~m}$

Volume of sphere $=\frac{4}{3} \pi r^{3}$

$=\left[\frac{4}{3} \times \frac{22}{7} \times(0.63)^{3}\right] \mathrm{m}^{3}$

$=1.0478 \mathrm{~m}^{3}$

Therefore, the volume of the sphere is $1.05 \mathrm{~m}^{3}$ (approximately).