Question

The area of a circle is 301.84 cm². Find its circumference.

Answer 1

Area of the circle = 301.84 cm²
We know:
Area of a circle$=\pi r^2$

$$\begin{gathered} \Rightarrow 301.84=\frac{22}{7}{r}^2 \\ \Rightarrow \frac{301.84\times 7}{22}=r^2 \\ \Rightarrow r^2=96.04 \\ \Rightarrow r=9.8\mathrm{cm} \end{gathered}$$

Now,
Circumference of the circle = $2\mathrm{\pi r}$
$$\begin{gathered} =2\times \frac{22}{7}\times 9.8 \\ =61.6\mathrm{cm} \end{gathered}$$