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

    Question

    A bag contains 7 green balls, 5 blue balls, and 10

    yellow balls. A box contains 3 green balls and 8 yellow balls. A ball is randomly drawn from the box and put into the bag, and then a ball is randomly drawn from the bag. Find the probability that the ball is of yellow color.
    A 69/155 Correct Answer Incorrect Answer
    B 118/253 Correct Answer Incorrect Answer
    C 49/135 Correct Answer Incorrect Answer
    D 59/122 Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    ATQ, Bag:  22 balls (10 yellow).  Box:  11 balls (8 yellow, 3 green).  Case 1: A yellow ball is added to the bag. Probability of drawing yellow from the box:  8/11.  Bag ha 11 yellow out of  23 balls: 11/23. Contribution: 8/11, 11/23 = 88/253.

    Case 2: A green ball is added to the bag. Probability of drawing green from the box: 3/11 Bag has 10 yellow out of 23 balls = 10/23 Contribution: 3/11, 10/23 = 30/253 .

    Total Probability:

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