Question

A cone has a height of 10 cm and a volume of 60 cubic cm. What isthe approximate circumference of the base of the cone?A. 4.8 cmB. 15.1 cmC. 18.1 cmD. 2.4 cm

Answer 1

Given:

Height of the cone is, h = 10 cm.

Volume of cone, V = 60 cubic cm.

The objective is to find the circumference of the base of the cone.

To find the circumference, the radius of base of the cone can be calculated as,

`\begin{gathered} V=(1)/(3)\pi r^2h \\ 60=(1)/(3)\pi r^2\cdot10 \\ r^2=(60\cdot3)/(\pi\cdot10) \\ r^2=(18)/(\pi) \\ r=\sqrt[]{(18)/(\pi)} \\ r=2.4\text{ cm.} \end{gathered}`

The circumference of the base can be calculated as,

Thus, the circumference of the base is 15.1 cm.

Hence, option (b) is the correct answer.