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

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

Ex Output:
3886.25


Ex Input:
Problem: what is 82 % of 3 / 5 ?

Ex Output:
0.492


Ex Input:
Problem: if x + y = 4 and x 2 y 3 + y 2 x 3 = 36 , what is the value of xy ?

Ex Output:

4