Question

ABCD is a flower bed. If OA = 21m and OC = 14m, then find the area of the bed in $m^2$.

Answer 1

Required area = Area of sector OAB – Area of sector OCD
$=\frac{\theta }{360}\times \pi (R^2-r^2)$

$=\frac{90}{360}\times \pi ({21}^2-{14}^2)$

$=\frac{1}{4}\times \pi \left(245\right)$

$=192.5m^2$