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.