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

Example Input: Problem: by investing in 1623 % stock at 64 , one earns rs . 1500 . the investment made is
Example Output: rs . 5760

Example Input: Problem: the average of first 17 even numbers is ?
Example Output: 18

Example Input: Problem: john makes $ 40 a week from his job . he earns a raise and now makes $ 80 a week . what is the % increase ?
Example Output:
100