A bag contains 4 violet, 2 grey and 6 black pullovers. 3 pullovers are chosen at random. What is the probability that at least 2 pullovers chosen will be violet?

There will be two cases: Case I: 2 violet, 1 (grey or black) Probability = 4C2 × 8C1/ 12C3 = 12/55 Case II: all violet Probability = ^{4}C_{3}/^{12}C_{3} = 1/55 Total probability = 12/55 + 1/55 = 13/55

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