A box contains 5 red and 7 blue marbles. If two marbles are drawn at random one after the other without replacement, what is the probability that both are red?

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A 5/33
B 25/144
C 5/12
D 7/22

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Answer: A. 5/33

• Answer: A) 5/33
• Explanation: Probability of first red = 5/12. Since there is no replacement, 4 red and 11 total marbles remain. Probability of second red = 4/11. Total probability = (5/12) × (4/11) = 20/132 = 5/33.

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A box contains 5 red and 7 blue marbles. If two marbles are drawn at random one after the other without replacement, what is the probability that both are red?

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