Question

A vessel is in the form of a frustum of a cone. Its radius at top end is 12 m and the bottom end is 10 m. Its volume is 369 $\pi m^3$. Find its height.

• A. 3.64 m
• B. 3.04 m
• C. 3.54 m
• D. 3.44 m

Answer 1

The correct option is B 3.04 m

Volume of a frustum cone = $\frac{\pi h}{3}(R^2+Rr+r^2)$

$369\pi$$=\frac{\pi \times h}{3}({12}^2+12\times 10+{10}^2)$

$369\times 3$ = $h(144+120+100)$

$1,107=h\left(364\right)$

h = 3.04 m