To find the circumference of a circle you would need to use the formula 2πr.
Since the diameter is twice the radius...
(Assuming that π = 3.14)
2 * 3.14 * (4 / 2)
2 * 3.14 * 2
6.28 * 2
= 12.56 cm
Answer: 25.13cm is the circumference of the diameter of 4cm.
7.2m questions
9.6m answers