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

Ex Input:
Problem: a student chose a number , multiplied it by 2 , then subtracted 138 from the result and got 102 . what was the number he chose ?

Ex Output:
120


Ex Input:
Problem: find ( 7 x + 2 y ) / ( x - 2 y ) if x / 2 y = 3 / 2 ?

Ex Output:
23


Ex Input:
Problem: if a ^ 2 is divisible by 240 what is the least possible value of integer a ?

Ex Output:

60