New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    A bag contains 6 red, 10 yellow, and 14 black balls. If

    2 balls are picked at random without replacement, find the probability that the first ball is red and the second ball is either yellow or black.
    A 148/45 Correct Answer Incorrect Answer
    B 48/147 Correct Answer Incorrect Answer
    C 24/145 Correct Answer Incorrect Answer
    D 48/59 Correct Answer Incorrect Answer
    E none of these Correct Answer Incorrect Answer

    Solution

    We have a bag with: 6 Red balls 10 Yellow balls 14 Black balls Total balls = 30 We pick two balls without replacement, and we need the probability that: First ball is Red. Second ball is either Yellow or Black. Step 1: Probability of picking a Red ball first First ball is Red. Second ball is either Yellow or Black. Probability of picking a Red ball first P(R1) = 6/30 = 1/5 Probability of picking a Yellow or Black ball next After picking a red ball, 29 balls remain. Yellow + Black balls left = 10+14 = 24. P(Y2 or B2) = 24/29 Multiply the probabilities P(R1 and (Y2 or B2)) = 1/5 × 24/29 = 24/145

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