SOLUTION: I need your help please!
A library has 3 books from each of 5 different authors.
How many ways can the library arrange the books on the shelf if books by the same author must be
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Permutations
-> SOLUTION: I need your help please!
A library has 3 books from each of 5 different authors.
How many ways can the library arrange the books on the shelf if books by the same author must be
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Question 788607: I need your help please!
A library has 3 books from each of 5 different authors.
How many ways can the library arrange the books on the shelf if books by the same author must be placed together? Answer by Edwin McCravy(20054) (Show Source):
You can put this solution on YOUR website! We can choose the author whose 3 books will be on the far left in 5 ways.
We can choose the author whose 3 books will be 2nd from the left in 4 ways.
We can choose the author whose 3 books will be in the middle in 3 ways.
We can choose the author whose 3 books will be 2nd from the right in 2 ways.
We can choose the author whose 3 books will be on the far right in only 1 way.
That's 5! ways to choose the order of authors left to right.
We can choose the order of books by the author whose books are on the far left in 3! ways.
We can choose the order of books by the author whose books are 2nd from the left in 3! ways.
We can choose the order of books by the author whose books are in the middle in 3! ways.
We can choose the order of books by the author whose books are 2nd from the left in 3! ways.
We can choose the order of books by the author whose books are on the far right in 3! ways.
Answer 5!*3!*3!*3!*3!*3! = 933120
Edwin
