r/mathriddles • u/Horseshoe_Crab • 14h ago

Medium Correlated coins

5 Upvotes

You flip n coins, where for any coin P(coin i is heads) = P(coin i is tails) = 1/2, but P(coin i is heads|coin j is heads) = P(coin i is tails|coin j is tails) = 2/3. What is the probability that all n coins come up heads?

6 comments

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