Haryana Police Constable Model Paper 9

Given:
Area of square $=484{\mathrm{cm}}^2$
Formula used:
Area of square $={\mathrm{side}}^2$
The perimeter of square $=4\times \mathrm{side}$
Area of circle $=\mathrm{\pi }{\mathrm{r}}^2$
The perimeter of circle $=2\mathrm{\pi }\mathrm{r}$
Where, $\mathrm{r}=$ radius of the circle
Calculation:
Let ‘ $\mathrm{r}$ ’ be the radius of the circle.
Area of square $={\mathrm{side}}^2$
Side of the square $\Rightarrow \sqrt{484}$ $=22\mathrm{cm}$
Length of the square $\Rightarrow 4\times 22=88\mathrm{cm}$
Now, the wire is bent into the circle
The radius of the circle $\Rightarrow 2\mathrm{\pi }\mathrm{r}=88\Rightarrow \mathrm{r}=14\mathrm{cm}$
Area of circle $\Rightarrow \mathrm{\pi }{\mathrm{r}}^2=\left(\frac{22}{7}\right)\times 14\times 14=616{\mathrm{cm}}^2$
∴ The area of the circle is $616{\mathrm{cm}}^2$ .