Question

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

Answer 1

Let the radius of the circle be r cm. Then, Diameter = 2r cm and Circumference = 2πr cm

It is given that the circumference exceeds the diameter by 16.8 cm

∴ Circumference = Diameter + 16.8

⇒ 2πr = 2r + 16.8

${\displaystyle \Rightarrow 2\times \frac{22}{7}\times r=2r+16.8}$

⇒ 44r = 14r + 16.8 × 7

⇒ 44r – 14r = 117.6 ⇒30 r = 117.6

${\displaystyle \Rightarrow r=\frac{117.6}{30}=3.92}$

Hence, radius = 3.92 cm