SOLUTION: What are the solutions: After several rounds of a card game, a deck of playing cards contains, 10 red-suited cards and 15 black-suited cards. Terry draws cards from this deck wit

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Question 588759: What are the solutions: After several rounds of a card game, a deck of playing cards contains, 10 red-suited cards and 15 black-suited cards. Terry draws cards from this deck without replacement until she has either two red cards or two black cards. To the nearest tenth of a percent, what is the probability that Terry draws two red cards?
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
(10C2)/25C2=45/300=0.15 Probability that the first 2 cards are red.
(15C2)/25C2=105/300=0.35 Probability that the first 2 cards are black.
1.00-.35-.15=.50 probability one card is red and the other black after two cards are drawn.
10/25 * .50 = .20 probability one card is red and the other black after two cards are drawn AND the card drawn is red.
.15 + .20 = .35 the probability that Terry draws two red cards.
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Ed