2018 PUMaC Live Round 2.3
Source:
January 13, 2019
PuMACLive Roundcountingdistinguishabilityprobabilityexpected value
Problem Statement
Sophie has indistinguishable pairs of socks in a laundry bag. She pulls them out one at a time. After pulling out socks, the expected number of unmatched socks among the socks that she has pulled out can be expressed in simplest form as . Find .