Hi all, this is my first post and I feel like I shouldn't even have to ask, but I'm having a tough time figuring this out. I watched an instructional video teaching how to solve for the arc of an angle and in the video, he divides a fraction and gets another fraction. My issue is I have no idea how he got the resulting fraction...

The expression was this (a = angle):

25pi/8 = 4.8a

125pi/192 = a

How does it simplify into a much larger number? According to the algebra I know, it's supposed to come out to 25pi/38.4 = a. What am I missing?

Thanks!