Couples in a Row
- kfoozminus
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In how many ways $4$ couples can stand in a row so that no one doesn't stand beside it's pair?
jannatul ferdows jenny
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Re: Couples in a Row
By Inclusion-Exclusion method,we get:
$8!-4\times7!\times2+6\times6!\times4-4\times5!\times8+4!\times16$.
$8!-4\times7!\times2+6\times6!\times4-4\times5!\times8+4!\times16$.
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