Mathematics

A rope of length 18m is used to form a sector of a circle of…

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