[BruceZ]

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There are 10 pairs of gloves (20 gloves), and 6 are selected at random. Let X be the number of pairs of gloves. Find the EV of X.

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Here's an easy way. The EV is the sum of the probabilities of each pair being selected, which is 10 times the probability that a particular pair is selected, which is
<font color="red">
Edited from:10*C(20,4)/C(20,6) = 1.25.</font>
<font color="blue">Edited to: 10*C(18,4)/C(20,6) =~ 0.7895