Question

Miguel is putting 9 books in a row on his bookshelf. He will put one of the books, The Iliad, in the first spot. He will put another of the books, The Odyssey, in the last spot. In how many ways can he put the books on the shelf?

Answer 1

5040

Explanation:

The first and last spots are already determined, so they do not factor into our probability. To find how many ways 7 books can be arranged on a shelf we can use the following model:

7 * 6 * 5 * 4 * 3 * 2 * 1 or 7!

The reason why the numbers are descending is because there is one less book that can do into each spot as we move along the shelf.