Reasoning

Opening Envelopes

Difficulty
You have two independent envelopes. Each envelope contains a card that is red with probability \( 1/2 \) and blue otherwise. 1) Given that at least one envelope contains a red card, what is the probability that both envelopes contain red cards? 2) Given that the first envelope you picked contains a red card, what is the probability the other envelope is red?
Reported at 2 firmsDa Vinci Trading · DE ShawI’ve seen this in an interviewI’ve seen this
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