In how many ways can 9 books be arranged on a shelf?

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Answer 1 · 2016-01-14T11:26:58

#9! = 362880# ways

Assume that all the books are distinct from one another.

There are:

9 ways to put the first book.

8 ways to put the second book after putting the first one.

7 ways to put the third book after putting the second one.

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1 way to put the ninth book after putting the eighth one.

Multiply all the different number of ways together to get nine factorial.