Question

Find the circumference and area of a circle of radius 8.4 cm.

Answer 1

We know that the circumference $C$ and area $A$ of a circle of radius $r$ are given by,

Circumference $=2\pi r$ and

Area of circle $=\pi r^2$

Here, $r=8.4cm.$

$\therefore$C $=$ circumference $=2\pi r$ $=2\times \frac{22}{7}\times 8.4=52.8cm$

A $=$ Area $=$ $\pi r^2$ $=$ $\frac{22}{7}\times 8.4\times 8.4c{m}^2=221.76c{m}^2$