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Counting & ProbabilityMediumInclusion–Exclusion, Derangements & Pigeonhole

Inclusion--Exclusion, Derangements & Pigeonhole · Medium problem

A permutation of {1,2,3,4,5}\{1,2,3,4,5\} is chosen at random. What is the probability it is a derangement? Give an exact fraction.

Express your answer as a common fraction.