Question 144558
Lets say that a family of 5 decides that instead of each person buying a present for each other person in the family, all the family members will put their names in a hat. Each person then takes one name out of the hat & buys a present for that person. What is the probability of every family member getting his or her own name? 
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Ans. if names are replaced: (1/5)^5 = 0.00032
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Answers if names are not replaced : (1/5)(1/4)(!/3)(1/2)(1/1) = 1/5! = 0.00833...
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Cheers,
Stan H.