A truck tire with a diameter of 36 in is rolling over level ground spinning at 11 rotations/second. If the speed limit is 55 miles per hour and the penalty is $20 per hour over the speed limit, should the driver be fined and if so, how much?

Answer 1

36 * pi in/rev * 11 rev/sec * 1mi/(5280*12)in * 3600s/hr = 71mph

so, the fine is $20*16 = $320