The angle of a sector of a circle is 108°. If the radius of the circle is 31/2cm, find the perimeter of the sector
-
A.
6 3/5cm -
B.
6 4/5cm -
C.
7 1/10cm -
D.
10 2/5cm -
E.
13 3/5cm,
Correct Answer: Option E
Explanation
Perimeter of sector = (frac{theta}{360°} times 2pi r + 2r)
= (frac{108}{360} times 2 times frac{22}{7} times frac{7}{2} + 2(frac{7}{2}))
= (6 frac{3}{5} + 7)
= (13 frac{3}{5} cm)