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

Example Input: Problem: pipe a can fill a tank in 6 hours . due to a leak at the bottom , it takes 10 hours for the pipe a to fill the tank . in what time can the leak alone empty the full tank ?
Example Output: 15

Example Input: Problem: a train traveling at 72 kmph crosses a platform in 33 seconds and a man standing on the platform in 18 seconds . what is the length of the platform in meters ?
Example Output: 300 meters

Example Input: Problem: how much time does a train 160 metres long running at 72 km / hr take to pass a pole ?
Example Output:
8 s