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

Ex Input:
Problem: two trains each 120 m in length each , are running on two parallel lines in opposite directions . if one goes at the speed of 85 km / h while the other travels at 65 km / h . how long will it take for them to pass each other completely .

Ex Output:
10.07 sec


Ex Input:
Problem: a contractor undertook to do a piece of work in 18 days . he employed certain number of laboures but 9 of them were absent from the very first day and the rest could finish the work in only 6 days . find the number of men originally employed ?

Ex Output:
4.5


Ex Input:
Problem: the probability that a number selected at random from the first 50 natural numbers is a composite number is

Ex Output:

17 / 25