Question

consider 3 urns. urn A contains 2 white and 4 red balls, urn B contains 8 white and 4 red balls, and urn C contains 1 white and 3 red balls. If 1 ball is selected from each urn, what is the probability that the ball chosen from urn A was white given that exactly 2 balls were selected?

Answer 1

2/9 probability

Answer 2

You see, there is a 2/6 chance of picking a white ball our of Urn A. There is a 2/3 chance of the person even drawing a ball from Urn A. Thus \[2/6\times2/3\] is 2/9.