Question

$AO=OB$ perimeter $=47=cm$
find the area of shaded region

Answer 1

Let radius is $r$.

Perimeter $=2r+2\pi r\times \frac{3}{4}$

$=2r+\frac{22}{7}\times r\times \frac{3}{2}$

$=2r+\frac{33r}{7}=47$

$\frac{47r}{7}=47$ , $r=7$ cm

Area $={\pi r}^2\times \frac{3}{4}$

$=\frac{22}{7}\times 7^2\times \frac{3}{4}=115.5{cm}^2$