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

Ex Input:
Problem: a certain social security recipient will receive an annual benefit of $ 12,000 provided he has annual earnings of $ 9,360 or less , but the benefit will be reduced by $ 1 for every $ 3 of annual earnings over $ 9,360 . what amount of total annual earnings would result in a 40 percent reduction in the recipient ' s annual social security benefit ? ( assume social security benefits are not counted as part of annual earnings . )

Ex Output:
$ 30,96


Ex Input:
Problem: a train running at the speed of 72 km / hr crosses a pole in 9 seconds . find the length of the train .

Ex Output:
180 meter


Ex Input:
Problem: 9 years ago i was 5 times as old as my eldest son . today i am 3 times his age . how old am i now ?

Ex Output:

54