Total number of books borrowed by 24 students (2+12+10) mentioned in the question = 32. The remaining 28 books should be divided among 6 students. If 5 guys get the least number of books, that is 3, then the 6th guy gets 13.

heshamelaziry wrote:In a class of 30 students, 2 students did not borrow any books, 12 students each borrowed 1 book, 10 students each borrowed 2 books, and the rest each borrowed at least 3 books.

If the average number of books borrowed per student was 2, what is the maximum number of books that any single student could have borrowed ?

For me, I have to think of these problems using the avg formula: Avg = sum/n

So, the sum will be the total number of books borrowed. We are given that the number of books that select students borrowed. 2 borrowed no books; 2*0 = 0; 12 students borrowed 1 book each, 12*1 = 12; 10 students each borrowed 2 books, 10*2 = 20; and the REST (6 students) borrowed AT LEAST 3 books WHERE we are supposed to find, out of these 6 students, what the max # books that one kid could borrow? We assume that 5 kids borrowed the least # of books, 5*3 = 15.

SO: (2*0+12*1+10*2+5*3+x)/30students = 2 per student
47+x = 60
x = 60-47 = 13

Hope that helped!