Bertrand's box
Three cards: one red on both sides, one black on both sides, one red on one side and black on the other. You draw a card at random and see a red face. What is the probability the other side is also red? Give a decimal.
Show hints (2)+
- Count faces that could be showing, not cards.
- Two of the three red faces are on one card.
Answer
Reveal answer →Final answer
0.6667 (± 0.005)
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