How does an officer calculate the fine for a speeding ticket?

Any speed over the speed limit within the first 10 M.P.H. is a fifty (50) dollar fine. The violator is accessed an additional $10.00 for each M.P.H. over ten m.p.h. For example, if the speed limit is 35 M.P.H. and a violator is stopped for traveling 50 m.p.h., the fine would be $100.00.