Question

An iron right circular cone of diameter $8cm$, and height $12cm$, is melted and recast into spherical lead shots each of radius $4mm$. How many lead shots can be made?

Answer 1

Given, diameter of the right circular cone $=8cm$

Therefore, radius will be $4cm$.

Also given, height $12cm$, radius of spherical lead shots $=4mm$.

We know, $10$ mm $=1cm$

Thus, $4mm=\frac{4}{10}cm$

Volume of right circular cone $=n\times$ $($ number of spherical lead shots $)$

$n=\frac{1}{3}\frac{\pi r^{2}h}{\frac{4}{3}\pi r^3}$

Putting all the value , we get

$n=3\times 5\times 5\times 10$

$n=750$

Therefore, $750$ lead shots can be made.