Question

What is the circumference of a circle with a diameter of 21 m? (use for pi)

Answer 1

D=21m
R=21/2=10.5m
C=2*pi*r
2*3.14*10.5
65.94

So circumference of a circle with a diameter of 21m is 65.94m

Answer 2

21π m, or ≈ 65.94 m

Explanation:

Remember that π is the ratio between a circle's circumference and its diameter, or, in equation form:

`\pi=(c)/(d)`

where c is the circumference and d is the diameter. If we want to find the circumference, we can just multiply that equation by d on both sides to get

`c=\pi d`

Here, our d = 21 m, so our circumference would be

`c=21\pi` m, or approximately 21(3.14) = 65.94 m