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expected number of coin tosses, variance


New member
Oct 28, 2007
A game is played with n fair coins starting with all coins showing tails. In each
round all coins that show tails are tossed; rounds continue until all coins show heads.
Let Xn be the number of rounds and Yn be the number of tosses. Find E(Yn) and
Var(Yn) for all values of n.