Question

The circumference of a circle is 3.14 m, find its area.

Answer 1

We have :

Circumference of the circle = 3.14 ​m = $2\mathrm{\pi r}$
$$\begin{gathered} \Rightarrow 3.14\mathrm{m}=\left(2\times \frac{22}{7}\mathrm{x}\mathrm{r}\right)\mathrm{m} \\ \Rightarrow r=\left(\frac{3.14\times 7}{2\times 22}\right)\mathrm{m}=\left(\frac{1}{2}\right)\mathrm{m}. \end{gathered}$$

Area of the circle (A) = ${\mathrm{\pi r}}^2$
$$\begin{gathered} \Rightarrow A=\frac{22}{7}\times {\left(\frac{1}{2}\right)}^2{\mathrm{m}}^2 \\ \Rightarrow A=\left(\frac{22}{7}\times \frac{1}{2}\times \frac{1}{2}\right){\mathrm{m}}^2=\left(\frac{22}{28}\right){\mathrm{m}}^2=0.785{\mathrm{m}}^2. \end{gathered}$$