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jp51378
Apr 26, 2007, 10:35 AM
Hey guys I am trying to work a problem similar to this

4 married couples are at a dance. The wives randomly select new partners from the 4 men they are with, what is the probability that no one dances with their spouse for the next dance?

PLEASE HELP... I'm completely lost

galactus
Apr 26, 2007, 12:35 PM
Drawing a little diagram would help.

There are 4 possible pairings if each person picks their correct spouse.

W1 H1, W2 H2, W3 H3, W4 H4

There are 4^2 possible pairings. Subtract the two to find the number of ways no one is paired with their spouse. Then find the probability.