The contents of three given urns I, II and III are as follows
- 1 white, 2 black and 3 red
- 2 white, 1 black and 1 red
- 4 white, 5 black and 3 red
One urn is chosen at random and two balls are drawn. They happen to be white and red. What is the probability they come from urns I, II or III?
Event = choose white and red ball
Total probability = P(urn 1) * P(event / urn 1) + P(urn 2) * P(event / urn 2) + P(urn 3) * P(event / urn 3)
where P(A/B) is the conditional probability. Is this the correct approach?