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

Ex Input:
Problem: in a class of 32 students , 2 students did not borrow any books from the library , 12 students each borrowed 1 book , 10 students each borrowed 2 books , and the rest borrowed at least 3 books . if the average number of books per student was 2 , what is the maximum number of books any single student could have borrowed ?

Ex Output:
11

Ex Input:
Problem: from a pack of cards , two cards are drawn one after the other , with replacement . what is the probability that the first card is a black card and the second card is a king ?

Ex Output:
1 / 26

Ex Input:
Problem: in a garment industry , 12 men working 9 hours per day complete a piece of work in 10 days . to complete the same work in 12 days , working 15 hours a day , the number of men required is :

Ex Output:
7