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Answer : 2 19/42 Explanation : Answer: B) 19/42 Explanation: A red ball can be drawn in two mutually exclusive ways (i) Selecting bag I and then drawing a red ball from it. (ii) Selecting bag II and then drawing a red ball from it. Let E1, E2 and A denote the events defined as follows:E1 = selecting bag I,E2 = selecting bag IIA = drawing a red ballSince one of the two bags is selected randomly, therefore P(E1) = 1/2  and  P(E2) = 1/2Now, PAE1 = Probability of drawing a red ball when the first bag has been selected = 4/7  PAE2  = Probability of drawing a red ball when the second bag has been selected = 2/6 Using the law of total probability, we have  P(red ball) = P(A) = PE1×PAE1 PE2×PAE2                            = 12×47 12×26=1942

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