Question

A frustum is made by removing a small cone from
a similar large cone.
Work out the volume of the frustum, below.
Give your answer in terms o

Answer 1

Answer:

$volume \ of \ cone = \frac{1}{3}\pi R^2h = \frac{1}{3} \pi 15 \cdot 15\cdot 16 = 1200\pi$

$volume \ of \ frustum \ = \frac{\pi h}{3} (R^2 + Rr+ r^2) \ where \ R \ is \ the \ base \ radius \ r \ is \ the \ top \ radius$Here r is not mentioned so we will keep it as r itself.

Substituting the values of R = 15cm and h of the frustum which is 4cm.

Volume of frustum :

                   $\frac{4\pi }{3} (15^2+ 15r + r^2)\\\\\frac{4\pi }{3} (225+ 15r + r^2)$