A bag has 4 red and 6 blue marbles. Two marbles are drawn one after the other without replacement. What is the probability that both are red?
Answer and explanation
Correct answer: A. ()
- Step 1: First red: ; then 3 red remain among 9 marbles: . Step 2. . **Answer: . Why not the others:** 4/25 assumes replacement, 2/5 is a single draw, and 1/3 uses a total that does not exist.
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