Question

Assume $\pi =\frac{22}{7}$ , unless stated otherwise.
Find the volume of a sphere whose radius is
(i) $7$ cm
(ii) $0.63$ m

Answer 1

Given

(i) Radius $=7$cm

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

$=\frac{4}{3}\times \frac{22}{7}\times 7\times 7\times 7$

Volume $=\frac{49\times 4\times 22}{3}=1437.2c{m}^3$

(ii) Radius $=0.63$m

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

$=\frac{4}{3}\times \frac{22}{7}\times 0.63\times 0.63\times 0.63$

$=0.12\times 22\times 0.63\times 0.63$

Volume of sphere $=1.04m^2$.