Madhya Pradesh Police Exam Model Paper 3

Given:
Ratio of area of 2 circles = 9 ∶ 16
Formula used:
Area of circle =πr2
Circumference of circle =2πr
Where,
r → Radius of circle
Calculation:
Let the radius of the circles be ‘R’ and ‘r’
∴ (Area of circle 1)/(Area of circle 2) =9/16
⇒πR2/πr2=9/16
⇒R2/r2=9/16
⇒R/r=√(9/16)
⇒R/r=3/4
(Circumference of circle 1)/(Circumference of circle 2) =2πR/2πr
(Circumference of circle 1) ∶ (Circumference of circle 2) = 3 ∶ 4
∴ Ratio of circumference of both the circles is 3 ∶ 4