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

Example Input: Problem: if x , y , and z are positive integers , and 3 x = 5 y = 6 z , then the least possible value of x + y + z is
Example Output: 21

Example Input: Problem: ( 935421 x 625 ) = ?
Example Output: 584638125

Example Input: Problem: the s . i . on a certain sum of money for 5 years at 10 % per annum is half the c . i . on rs . 5000 for 2 years at 12 % per annum . the sum placed on s . i . is ?
Example Output:
127