A circle of diameter $\displaystyle 20$ cm is equally divided into five sectors. Find the area and perimeter of one of the sectors.

Here, radius = $\displaystyle 10$ cm Central angle of each sector \(\displaystyle =\frac{360^{\circ}}{5}=72^{\circ}\) Area of one sector \(\displaystyle =\frac{72}{360} \times \frac{22}{7} \times 10 \times 10\) \[=\frac{440}{7} \mathrm{~cm}^{2} \text { or } 62.8 \mathrm{~cm}^{2} \text { (approx.) } \] Perimeter of one sector \(\displaystyle =\frac{72}{360} \times 2 \times \frac{22}{7} \times 10+10+10\) \[=\frac{228}{7} \mathrm{~cm} \text { or } 32.5 \mathrm{~cm} \text { (approx.) } \]