Three prisoners
Three prisoners A, B, C will have exactly one pardoned, chosen uniformly at random. A asks the guard to name one of B, C who will be executed; the guard truthfully names B (choosing fairly between B and C if both are doomed). Given this, what is the probability that A is pardoned? Give your answer as a decimal (to 2 decimals).
Show hints (2)+
- The guard never names A, so his answer says nothing new about A.
- Apply Bayes' rule with the guard's tie-breaking probability for B vs C.
Answer
Reveal answer →Final answer
0.33 (± 0.01)
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Asked at: Jane Street, SIG