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2 votes
2 votes
4 person wearing different hat went to restaurant, they gave there hat to manager, manager has habit of forgetting thing while returning manager gave hat back to each person, probability that none of the person gets there respective hats is ?

2 Answers

8 votes
8 votes

Total Number of ways 4 hats can be arranged/distributed = 4!=24

Number of degeneration of four numbers will give number of arrangements where no one gets correct hat.

$4!/2! - 4!/3! +4!/4! $

$=24/2 - 24/6 +1$

$=12-4+1$

$9$

Probability that no one gets correct  hat=$9/24$=.375

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