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

Ex Input:
Problem: a 270 metres long bullet train running at the speed of 120 kmph crosses another bullet train running in opposite direction at the speed of 80 kmph in 9 seconds . what is the length of the other bullet train ?

Ex Output:
230

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

Ex Output:
- 4.

Ex Input:
Problem: find the least number must be subtracted from 62575 so that remaining number is divisible by 99 .

Ex Output:
7