Circumference of the circle

In our previous blog we learned about area of circles problems. Now let us learn about Circumference of the circle.

The distance around the circle is called the Circumference.

π is the ratio of circumference of the circle to the diameter. This relationship is expressed as

C/d = π, here C = circumference, d = diameter

There are two equivalent formulas for arriving to the circumference of a circle one using the diameter and the other using the radius of the circle. They are :

1. Circumference = π * d (d= diameter)

2. Circumference = 2 * π * r (r = radius)

The π value is usually taken as 3.14

solving circumference word problems

1. The diameter of a circle is 6 cm. What is the Circumference?

Solution:

Given, diameter = 6cm or radius = d/2 = 6/2 = 3cm

We have, Circumference = π * d (π=3.14)

= 3.14 * 6

= 18.84 cm Answer

OR

Circumference = 2 * π * r (π= 3.14)

= 2 *3.14 * 3

= 3.14 * 6

= 18.84 cm Answer

I hope the above explanation was useful.Keep reading and leave your comments.