How to convert points to radians in Objective-C?

In my app I'm using UIBezierPath to draw an arc into a circle. I'm trying to correlate a number to radians. So let's say a user has a certain number of points, and the points are capped at 100 points. I want 100 points to be 360 degrees. I want the first 33% of the circle to be green, and then from 34% to the next 66% of the circle to be stroked in orange, and then from 67% to 100% in red.

The issue I'm having here is converting percents of a circle to radians. When creating a UIBezier path, I need to provide a startAngle and endAngle, and I'm having a bit of trouble converting these points to radian values.

How would I go about solving this?



CGFloat radians = percent * 0.01 * 2 * M_PI;

Simple algebra.