You need to compute
Where
A=ball chosen from urn A was white
and
B=exactly 2 white balls were selected.
Hey
I've just been stuck on this question for a while and can't seem to figure out how to do it. I would appreciate any help.
Problem:
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 white balls were selected.
Thanks!
I don't know about all that A-complement stuff
JUST write down what B and AB are....
and figure out the probability of those events
FOR example, the event AB isn't so hard.
It consists of two mutually exclusive events... OR
where the subscript denotes which urn.
BY independence and since we are only selecting ONE marble, that probability is
(2/6)(4/12)(1/4)+(2/6)(8/12)(3/4)
B consists of those two events and only one more ...