Question

A cone has a volume of 462 cu cm and a height of 9 cm. Find the radius of its base.

Answer 1

Radius of cone (r) =?
Height of cone (h) = 9 cm
Volume of cone = 462 cu cm
Volume of a cone =$\frac{1}{3}\mathrm{\pi }{r}^{2}h$
$$\begin{gathered} \Rightarrow 462=\frac{1}{3}\times \frac{22}{7}\times r^2\times 9 \\ \Rightarrow r^2=\frac{462\times 3\times 7}{22\times 9} \\ \Rightarrow r^2=49 \\ \Rightarrow r=7cm \end{gathered}$$