Which coin produced two heads?
One of two coins is picked at random: a fair coin, and a coin that lands heads with probability . You flip the chosen coin twice and get two heads. What is the probability you picked the biased coin? Give your answer as a decimal (to 2 decimals).
Show hints (2)+
- Likelihood of HH is for the biased coin and for the fair coin.
- Both coins are equally likely a priori, so just compare likelihoods.
Answer
Reveal answer →Final answer
0.69 (± 0.01)
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