Question

Points $A$ and $B$ lie on circle $O$ (not shown). $AO=3$ and $\angle AOB={120}^o$. Find the area of sector $AOB$.

• A. $\frac{\pi }{3}$
• B. $\pi$
• C. $3\pi$
• D. $9\pi$

Answer 1

The correct option is C $3\pi$

Area of a sector is given by $\frac{\theta }{360}\times \pi \times r^2$ where $\theta$ is the angle made by the sector, $r$ is the radius of the circle.

Here, $\theta ={120}^o$ and $r=3$

$\therefore$ area of sector $=\frac{120}{360}\times \pi \times 9=3\pi$