Brain Teasers & Mental Math
A bag has 2 fair coins and 1 two-headed coin. You pick one at random and flip a head. What is the probability you picked the two-headed coin?
Model answer
Bayes. P(2H) = 1/3, P(head | 2H) = 1; P(fair) = 2/3, P(head | fair) = 1/2. P(2H | head) =…
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