The perimeter of a sector of a circle of radius... - WAEC Mathematics 2016 Question
The perimeter of a sector of a circle of radius 21cm is 64cm. Find the angle of the sector [Take (\pi = \frac{22}{7})]
A
70o
B
60o
C
55o
D
42o
Ask EduPadi AI...
Correct Option: B
Perimeter of a sector
= 2r + (\frac{\theta}{360^o}) x 2 x (\frac{22}{7}) x 21
64 = 2 x 21 + (\frac{\theta}{360^o}) x 2 x (\frac{22}{7}) x 21
64 = 42 + (\frac{\theta}{360^o}) x 44 x 3
64 - 42 = (\frac{\theta}{360^o}) x 11 x 3
22 = (\frac{33\theta}{90})
(\theta = \frac{22 \times 30}{11})
= 60o
Please share this, thanks:
#WAEC #WAEC
Add your answer
No responses