Question
A box contains 5 red, 7 blue and 8 green balls. If two
balls are drawn at random without replacement, what is the probability that both are blue?Solution
ATQ, Total balls = 5 + 7 + 8 = 20 Probability of first blue = 7/20 Probability of second blue = 6/19 Required probability = (7/20) x (6/19) = 42/380 = 21/190 Hence, the correct answer is 21/190.
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