SOLUTION: Bag I contains 3 red and 4 black balls while another Bag II contains 5 red and 6 black balls. One ball is drawn at random from one of the bags and it is found to be red. Find th

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Question 1045315: Bag I contains 3 red and 4 black balls while another Bag II contains 5 red
and 6 black balls. One ball is drawn at random from one of the bags and it is
found to be red. Find the probability that it was drawn from Bag II.

Found 2 solutions by Boreal, robertb:
Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website!
=======Bag 1=========Bag2-----T
R---------3----------------5---------8
B---------4----------------6--------10
T---------7----------------11--------18
Probability of a red ball (8 altogether) being drawn from Bag II is 5/8

Answer by robertb(5830) (Show Source):
You can put this solution on YOUR website!
The conditional probability
P(|Red) = P(∩Red)/P(Red)
holds.
Now P(Red) = P(∩Red) + P(∩Red)
= P(Red|)*P() + P(Red|)*P()
=.

===> P(|Red) = P(∩Red)/P(Red) =