The circular dart board has a diameter of 18 inches. So, its radius is 18/2 = 9 inches.

Therefore its area is pi*r^2 = pi*9^2

This is divided into 20 equal sectors.

**So the area of each sector is pi*81/20 = 12.72 square inch approximately.**

The circular dart board has a diameter of 18 inches. So, its radius is 18/2 = 9 inches.

Therefore its area is pi*r^2 = pi*9^2

This is divided into 20 equal sectors.

**So the area of each sector is pi*81/20 = 12.72 square inch approximately.**