Question

A bucket is in the form of a frustum of a cone and it can hold 28.49 litres of water. If the radii of its circular ends are 28 cm and 21 cm, find the height of the bucket.

Answer 1

Volume = 28.49 litres

$\Rightarrow$ 28.49 x 1000 $\Rightarrow$ 28490 $c{m}^3$

R = 28 cm

r =21 cm

Volume = $\frac{1}{3}$ $\times$$\pi$h[$R^2$ + $r^2$ + Rr]

$\Rightarrow$ (28490 = $\frac{1}{3}$ $\times$ $\frac{22}{7}$ $\times$ h [ 784 + 441 + 588 ]

$\Rightarrow$ 28490 = ​​​​​​​ $\frac{1}{3}$ $\times$ $\frac{22}{7}$ × 1813 h

On solving,

$\Rightarrow$ h = 15 cm