You can put this solution on YOUR website! a reduced deck of 4 Jacks and 4 Queens is shuffled. if two cards are picked at random, what is the probability that the second is a queen, given that the first is a jack?
Since we know that the first card is a jack, then we know that the second card
was from a deck that did not contain it. It was from a 7-card deck that
contained only 3 jacks and 4 queens, so the probability that it is a queen is 4
out of 7 or 4/7.
Edwin
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