Question

The circumference of a circle exceeds its diameter by 30 cm then its radius is

Answer 1

Hi ,

Let C and d are circumference and

diameter of a circle ,

C = d + 30 ( given )

We know that ,

C = πd

d + 30 = πd

2r + 30 = π × 2r

r + 15 = πr

15 = πr - r

15 = r( π - 1 )

15 = r ( 22/7 - 1 )

15 = r ( 22 - 7 )/7

15 = r ( 15/7 )

15 × ( 7/15 ) = r

7 = r

Therefore ,

radius = r = 7 cm

I hope this helps you.

: )