Question
A bag contains 4 black balls, 6 white balls and 5 red
balls. Two balls are drawn simultaneously. Find the probability that both the balls are of same colour.Solution
Total number of balls in the bag = 4 + 6 + 5 = 15 Total possible outcomes = 15C2 = 105 Number of favourable outcomes = 4C2 + 6C2 + 5C2 = 6 + 15 + 10 = 31 Required probability = 31/105
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