Question 464860
6 people queue up to get on the bus. Is 2 specific person refuse to follow each other, how many ways are possible?
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If the 2 were more flexible: 6! = 720 ways to line up
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If the 2 always queued together: 2*5! = 240 ways to line up
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Problem condition # of lineups = 720-240 = 480 ways
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Cheers,
Stan H.
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