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

Ex Input:
Problem: 17 balls are numbered 1 to 17 . a ball is drawn and then another ball is drawn without replacement . what is the probability that both balls have even numbers ?

Ex Output:
7 / 34


Ex Input:
Problem: in a room filled with 6 people , all 6 people have exactly 2 siblings in the room . if two individuals are selected from the room at random , what is the probability that those two individuals are not siblings ?

Ex Output:
3 / 5


Ex Input:
Problem: twelve machines , each working at the same constant rate , together can complete a certain job in 6 days . how many additional machines , each working at the same constant rate , will be needed to complete the job in 3 days ?

Ex Output:

12