# Area and circumference of a circle.

### By- Isabella Plumb

## Example 1.

## What Is the area and circumference of a circle and why do we use it?

A circle is a shape with all points the same distance from the center. It is named by the center.

The circle to the left is called circle A since the center is at point A. If you measure the

distance around a circle and divide it by the distance across the circle through the center, you will always come close to a particular value,

depending upon the accuracy of your measurement. This value is approximately 3.14159265358979323846... We use the Greek letter to represent this value. The number

## Circumference

The distance around a circle is called the circumference. The distance across a circle through the center is called the diameter.

Pi is the ratio of the circumference of a circle to the diameter.

for any circle, if you divide the circumference by the diameter, you get a value close to Pi. This relationship is expressed in the following formula:

## Citation

"Circumference".

*Mathgoodies.com*. N.p., 2016. Web. 10 May 2016.