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Problems › Probability

Bayesian Coin Identification

Probability · Easy · Free problem
You have two coins: Coin A is fair ($p = 0.5$) and Coin B is biased ($p = 0.7$). You pick one uniformly at random and flip it 5 times, observing 4 heads and 1 tail. What is the posterior probability that you are holding Coin B?

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