# How relate the length of a conveyor belt between two interlocked circles?

I'm trying to solve this problem:

Two wheels are one next to another and linked by a conveyor belt. How to express the length of the radius of the smaller wheel in terms of the length of the belt? Note that the size of the radius of A is three times the radius of B.

Let the length of the belt be $b$.
• Mind sharing what software did you used to sketch the graphics and label the angles and the lenghts?. Plus, how can be proved that the $PO_{1}O_{2}$ angle formed on the bigger wheel and $BO_{2}$ in the smaller one are the same?. – Chris Steinbeck Bell Oct 4 '17 at 2:56
• @ChrisSteinbeckBell The software appears to be $\LaTeX$ – gen-z ready to perish Oct 4 '17 at 2:57
• @ChrisSteinbeckBell Share$\LaTeX$ – gen-z ready to perish Oct 4 '17 at 3:02