<PRE><B>Question 710403</B>
A box contains 4 red marbles and 3 blue marbles. 2 marbles are drawn at random without replacement. What is the probability that the second marble drawn is blue given that:
(a) the first marble drawn is red 
P(blue | red) = 3/(3+3) = 1/2
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(b) the first marble drawn is blue 
P(blue | blue) = 2/6 = 1/3
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Cheers,
Stan H.
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