20.4 Circumference

borrowed from wikihow.com

Below is an explanation from aaamath.com

The circumference of a circle is the distance around the outside of the circle. It could be called the perimeter of the circle.

How to find the circumference of a circle:

• The circumference of a circle can be found by multiplying pi ( π = 3.14 ) by the diameter of the circle.
• If a circle has a diameter of 4, its circumference is 3.14*4=12.56
• If you know the radius, the diameter is twice as large.

Check your understand with the quiz at the bottom of this tutorial from mathgoodies.com