First the standard transliteration of [itex]\pi[/itex] is "pi", not "pie". That is what jbunnii was saying.
Second, Since degrees and radians measure the same thing, they are proportional: the ratio of radian measure to degree measure for the same angle is always the same: If an angle has degree measure d and radian measure r, then
[tex]\frac{r}{d}= \frac{\pi}{180}[/itex]
so
[tex]r= d\left(\frac{\pi}{180}\right)= \frac{d}{180} \pi[/tex]