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

Ex Input:
Problem: if | x - 9 | = 3 x , then x = ?

Ex Output:
- 4.


Ex Input:
Problem: if the average ( arithmetic mean ) of a and b is 45 and the average of b and c is 80 , what is the value of c − a ?

Ex Output:
60


Ex Input:
Problem: what is the sum of the greatest common factor and the lowest common multiple of 16 and 72 ?

Ex Output:

152