where is the example
I can't answer the question without the example provided, but here are some steps to solve it.
Basic info-
Circumference (C)
3.14 is used for pi π= 3.14
The line halfway of the circle is the radius(r)
The line through the circle is the diameter(d)
Formulas:
C= 2πr
2 × 3.14 × the radius
OR
C= πd
3.14 × the diameter