Find the circumference, diameter=84cm use 3.14 for pie

3.14 times 84 which is 263.76

The formula used to find circumference is

C=2 (3.14 or pie) (radius)

To find the radius you need to divide the diameter by 2:

84/2 = 42

So the radius is 42 so you have to do:

C=2 (3.14) (42)

So you get a total answer of 263.76cm