Question

The shaded region above represents 3/4 of the circle. If the radius of the circle is 3 inches, what is the perimeter of the sector in terms of ?

Answer 1

To find the perimeter of the sector (3/4 of the circle) you will find what 3/4 of the circumference of the entire circle would be and then add the radius twice (for each of the two straight sides).

Here are the steps:

1.  C = 3/4 x pi x d
           0.75 x 3.14 x 6 in
    C (3/4 of it) = 14.13 inches.

2.  14.13 inches + 3 inches + 3 inches = 20.13 inches

The perimeter of the sector is approximately 20.13 inches.