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January 13th, 2018, 09:51 AM   #1
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Probablity - round table

How many ways there is when sitting next to round table of n-chairs?
How many ways there is if Dan and David don't want to sit together?
What is the formula?
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January 13th, 2018, 12:47 PM   #2
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Sitting how many people? n?
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January 13th, 2018, 01:39 PM   #3
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Yes, n people.
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January 13th, 2018, 02:07 PM   #4
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Quote:
Originally Posted by policer View Post
Yes, n people.
suppose the table was linear rather than circular.

how many different ways could you arrange n people?

now given that table is circular, how many of those arrangements are in fact identical for a given arrangement.

given the two answers above what is the formula for the # of arrangements around an n seat circular table?
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January 13th, 2018, 05:03 PM   #5
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Quote:
Originally Posted by policer View Post
How many ways there is if Dan and David don't want to sit together?
No way if n < 4
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January 15th, 2018, 01:54 AM   #6
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I don't know

Quote:
Originally Posted by romsek View Post
suppose the table was linear rather than circular.

how many different ways could you arrange n people?

now given that table is circular, how many of those arrangements are in fact identical for a given arrangement.

given the two answers above what is the formula for the # of arrangements around an n seat circular table?
I have no idea how to solve this question? Please give me more hints.
And why n >= 4 (because of the round table (?!))?
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January 15th, 2018, 04:17 AM   #7
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If n = 3, then 3 chairs only:
so they have to be next to each other, being a round table!
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January 15th, 2018, 04:35 AM   #8
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What about n = 1?
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January 15th, 2018, 05:08 AM   #9
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Easy: Dan and David kiss n' make up, Dan sits on David's lap
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