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

Example Input: Problem: 20 is subtracted from 80 % of a number , the result is 60 . find the number ?
Example Output: 100

Example Input: Problem: a no . when divided by 281 gives a remainder 160 , what remainder will be obtainedby dividingthe same no . 21 ?
Example Output: 21

Example Input: Problem: find the principle on a certain sum of money at 9 % per annum for 2 2 / 5 years if the amount being rs . 1120 ?
Example Output:
921.0