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April 27th, 2018, 12:48 AM   #1
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Why did we subtract 1 from 5?

If 4 persons are invited for a party, find the number of ways in which they can be seated around a table along with the host.

Solution: Including the host, we have five persons. Now, 5 persons can arrange themselves around a table in (5-1)! = 4! = 24 ways.
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April 27th, 2018, 04:09 AM   #2
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Because they are only counting the relative positions. Everybody shifting one or two places to the left, for example, would be counted as the same order.
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April 27th, 2018, 09:17 AM   #3
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Quote:
Originally Posted by Country Boy View Post
Be.....der.
Can you show it in diagram?
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April 27th, 2018, 10:31 AM   #4
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Seating.PNG
The arrangements above have different positions for H (the host) but would be counted as the same if the seating order is all that matters.
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