Question 475749
12 books be divided between A and B so that one may get 9 books and the other student 3 books.

case 1:  when A will get 9 books and B will get 3 books

number of ways = 12C9 * 3C3 = 220


case 2:  when A will get 3 books and B will get 9 books

number of ways = 12C3 * 9C9 = 220


total number of ways = 220 + 220  = 440


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