Question

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

Answer 1

Let radius of circle = r cms

Diameter(d) = 2 × 𝑟𝑎𝑑𝑖𝑢𝑠 = 2𝑟

Circumference (c) = 2𝜋r

Given circumference exceeds diameter by 16.8cm

C = d + 16.8

⇒ 2𝜋r = 2r + 16.8

⇒ 2r(𝜋 – 1)= 16.8

⇒ 2r ×`(22/7− 1)`= 16.8

⇒ 2r ×`15/7`= 16.8

⇒ r =`(16.8×7)/30 = 5.6 × 0.7`

⇒ r = 3.92 cms

Circumference = 2𝜋r`= 2 × 22/7 × 3.92`

`= 2464/100 = 24.64` 𝑐𝑚𝑠