Each of 111 people names his or her 5 favorite movies out of a list of 11 movies. (a)
Chapter 4, Problem 68(choose chapter or problem)
Each of 111 people names his or her 5 favorite movies out of a list of 11 movies. (a) Alice and Bob are 2 of the 111 people. Assume for this part only that Alices 5 favorite movies out of the 11 are random, with all sets of 5 equally likely, and likewise for Bob, independently. Find the expected number of movies in common to Alices and Bobs lists of favorite movies. (b) Show that there are 2 movies such that at least 21 of the people name both of these movies as favorites.
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