A rope of length 18m is used to form a sector of a circle of radius 3.5m on a school playing field. What is the size of the angle of the sector, correct to the nearest degree?
-
A.
33o -
B.
40o -
C.
90o -
D.
180o -
E.
270o
Correct Answer: Option D
Explanation
Circumference = 2πr
2 x 22/7 x 3.5 ≅ 22m
22m = 360o
11m = 360/22 x 11 = 180o