A bag contains 6 red and 3 blue marbles. Two marbles are drawn at random without replacement. What is the probability that both are red?
Answer and explanation
Correct answer: D.
- Step 1: First draw red: ; second draw red: . Step 2. Probability: . **Answer: . Why not the others:** treats the draws as independent (with replacement); counts only the first draw; doubles the first probability.
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