What is formula for circumfrences

The circumference of a circle, which is another way of saying the perimeter of a circle, can be found using the formula 2πr.

Note that π represents the irrational number 3.14159... which

rounds to 3.14 and r represents the radius of the circle.

Therefore, since π = 3.14, another way of writing the formula

for the circumference of a circle is 2 · 3.14r or 6.28r.

circumference = 2 π r

or

circumference = π d

Step-by-step explanation:

r = radius of a circle

d = diameter

therefore

circumference = 2 π r

or

circumference = π d