PYQ Vault
EbooksTutor

A ball is moved from one bag to another, then a ball is drawn

This type of question, asked 3 times: 29 Jul 2022, 29 Jan 2025, 23 Jan 2026 S2. All 3 questions below, oldest first.

Try each one first, then open its answer.

  1. Question 1

    29 Jul 2022

    166
    Bag I contains 3 red, 4 black and 3 white balls and Bag II contains 2 red, 5 black and 2 white balls. One ball is transferred from Bag I to Bag II and then a ball is draw from Bag II. The ball so drawn is found to be black in colour. Then the probability, that the transferred ball is red, is:

    Tap an option to check your answer.

  2. Question 2

    29 Jan 2025

    141
    Bag 1 contains 4 white balls and 5 black balls, and Bag 2 contains nn white balls and 3 black balls. One ball is drawn randomly from Bag 1 and transferred to Bag 2. A ball is then drawn randomly from Bag 2. If the probability, that the ball drawn is white, is 29/4529/45, then n is equal to:

    Tap an option to check your answer.

  3. Question 3

    23 Jan 2026 S2

    61
    Bag A contains 9 white and 8 black balls, while bag B contains 6 white and 4 black balls. One ball is randomly picked up from the bag B and mixed up with the balls in the bag A . Then a ball is randomly drawn from the bag A . If the probability, that the ball drawn is white, is pq,gcd(p,q)=1\frac{p}{q},gcd(p,q) = 1, then p+qp + q is equal to

    Tap an option to check your answer.