Re: Inclusion-Exclusion Principle

Little wrote:
> Could someone explain to me how to use the Inclusion-Exclusion
> Principle to solve this problem.
> Question: A carousel has eight seats, each seat is distinct. Eight
> girls are seated on the carousel facing forward ( each girl looks at
> another girl's back). In how many ways can they change seats so that
> each has a different girl in front of her? How can the problem change
> when the seats are identical?
> Thanks a lot for the help.

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--- Christopher Heckman