A circle with a radius of $18 \mathrm{cm}$ has a sector with a central angle of $120°$ . Find the area of the sector. Use ($\pi =3.14$).

If r is the circle's radius, then the area of the sector of the angle $=\frac{\theta }{{360}^{°}}\times \pi r^2$

Given, radius, $\mathrm{r}=18 \mathrm{cm}$, central angle $\mathrm{\theta }=120° \mathrm{and} \mathrm{\pi }=3.14$

$\text{Area of sector }=\frac{\theta }{{360}^{°}}\times \pi r^2$

$=\frac{{120}^{°}}{{360}^{°}}\times 3.14\times 18\times 18$

$=\frac{1}{3}\times 3.14\times 324$

$=3.14\times 108$

$=339.12$

Hence, the area of the sector is $339.12{ \mathrm{cm}}^2$.