SOLUTION: A box contains 3 blue and 2 red marbles while another box contains 2 blue and 5 red marbles. A marble drawn at random from one of the boxes turns out to be blue. What is the probab
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-> SOLUTION: A box contains 3 blue and 2 red marbles while another box contains 2 blue and 5 red marbles. A marble drawn at random from one of the boxes turns out to be blue. What is the probab
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Question 1022485: A box contains 3 blue and 2 red marbles while another box contains 2 blue and 5 red marbles. A marble drawn at random from one of the boxes turns out to be blue. What is the probability that it came from the first box? Answer by robertb(5830) (Show Source):
You can put this solution on YOUR website! Apply Bayes' Theorem directly:
P(1st box|blue) = P(1st box AND blue)/P(blue) = P(blue|1st box)*P(1st box)/P(blue) = P(blue|1st box)*P(1st box)/[P(blue|1st box)*P(1st box) + P(blue|2nd box)*P(2nd box)] = .
