Question

Mr. Jones has 10 books that he is going to put on his bookshelf. Of these, 4 are mathematics books, 3 are chemistry books, 2 are history books, and 1 is a language book. Jones wants to arrange his books so that all the books dealing with same subject are together on the shelf. How many different arrangements are possible?

Answer 1

Explanation:

We consider 4 math books as one unit, 3 chemistry books as one unit and 2 history books as one unit and 1 language book as another unit(He wants to arrange his books so that all books dealing with same subject are together on the shelf)

Number of different arrangements possible = number of arrangements of 4 objects = 4! = 4 * 3 * 2 * 1 = 24