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    Question

    Bag 'A' contains 5 white and 2 black balls. Bag 'B'

    contains 2 white and 3 black balls. If any one bag is chosen and a ball is taken out of it at random, what is the probability that the ball is black?
    A 31/70 Correct Answer Incorrect Answer
    B 1/2 Correct Answer Incorrect Answer
    C 5/12 Correct Answer Incorrect Answer
    D 3/5 Correct Answer Incorrect Answer

    Solution

    Bag A=5White, 2 Black balls Bag B=2 White, 3 Black balls. Probability of selecting a bag = 1/2 Now, the Probability of picking a black ball = from bag A or from bag B = ²C ₁ /³C ₁ + ³C ₁ /³C ₁ =2/5+3/5 = 1 So, required probability = (1/2) *1 = 1/2

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