Question
A bag contains 5 red balls, 4 blue balls, and 3 green
balls. If three balls are drawn randomly, what is the probability that all three balls are of different colors?Solution
Total balls = 5 + 4 + 3 = 12. Total ways to choose 3 balls = 12C3 = 220. Favorable ways = 5C1 × 4C1 × 3C1 = 5 × 4 × 3 = 60. Probability = 60/220 = 3/11. Correct option: b
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