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

Example Input: Problem: mixture contains alcohol and water in the ratio 4 : 3 . if 5 liters of water is added to the mixture , the ratio becomes 4 : 5 . find the quantity of alcohol in the given mixture .
Example Output: 10

Example Input: Problem: a train 150 m long is running at a speed of 68 kmph . how long does it take to pass a man who is running at 8 kmph in the same direction as the train ?
Example Output: 9 sec

Example Input: Problem: a group of 8 friends want to play doubles tennis . how many different ways can the group be divided into 4 teams of 2 people ?
Example Output:
10