Question 455424
A box contains 2 white balls and 3 black balls. 2 balls are selected at random what is the probability that one is black and one is white.
a)balls are chosen with replacement
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P(2 black) = (3/5)(3/5) = 9/25
P(2 white) = (2/5)(2/5) = 4/25
P(black/white) = 1 - (13/25) = 12/25 
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b)Balls are chosen without replacement
P(2 black) = (3/5)(2/4) = 6/20
P(2 white) = (2/5)(1/4) = 2/20
P(black/white) = 1 - 8/20 = 12/20 = 3/5
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Cheers,
Stan H.