The task is to generate the correct answer for a given math problem.

Problem: on a certain road , 10 % of the motorists exceed the posted speed limit and receive speeding tickets , but 20 % of the motorists who exceed the posted speed limit do not receive speeding tickets . what percent of the motorists on that road exceed the posted speed limit ?
12.5 %

Problem: find compound interest on $ 10000 at 15 % per annum for 2 years 4 months , compounded annually .
3886.25

Problem: a train covers a distance of 12 km in 10 minutes . if it takes 4 seconds to pass a telegraph post , then the length of the train is
80 m