Circumference of a circle: 2 * Pi * R
1. Calculate radius from diameter.
Radius = Diameter/2
Radius = 15/2
Radius = 7.5cm
Formula to calculate the circumference:
2 * Pi * R
= 2 * Pi * 7.5
= 15 * Pi
= About 47.10 cm in terms of Pi.
So, in conclusion, the circumference if this circle is about: 47.10cm.