Q1 of 33 Page 12

The circumference of a circle exceeds the diameter by 16.8 cm. Find the radius of the circle.

Given: Diameter of circle = 16.8 cm


To find: The radius of the circle.


Explanation:


Let the radius of the circle be “r” cm.


⇒ D=2r cm and Circumference = 2πr cm


According to the given question,


2πr = 2r + 16.8



⇒ 44 r = 7(2r + 16.8)


⇒ 44r = 14r + 117.6


⇒ 44r – 14r = 117.6


⇒ 30r = 117.6


⇒ r = 3.92 cm


Hence the radius is 3.92 cm.


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