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

Example Input: Problem: the least number which should be added to 1789 so that the sum is exactly divisible by 5 , 6 , 4 and 3 is ?
Example Output: 11

Example Input: Problem: calculate the sum of first 60 natural numbers .
Example Output: 1830

Example Input: Problem: half a number plus 7 is 17 . what is the number ?
Example Output:
2