Question

A bag contains 5 blue and 4 black balls. Three balls are drawn at random. What is the probability that 2 are blue and 1 is black?

Answer 1

On drawing three balls from it, there are a total of 4 outcomes as follows:

1. 3 blue balls.

2. 2 blue balls and 1 black ball.

3. 1 blue ball and 2 black balls.

4. 3 black balls.

As one among the total probabilities is of 2 blue balls and 1 black ball, the no. of favourable outcomes is 1.

Therefore, probability is 1/4.

Thank you.