SOLUTION: Five balls are selected at random without replacement from an urn containing three white balls and five blue balls. Find the probability that two or three of the balls are white.

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Question 507246: Five balls are selected at random without replacement from an urn containing three white balls and five blue balls. Find the probability that two or three of the balls are white.
The "two OR three of the balls are white" is confusing me!
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Five balls are selected at random without replacement from an urn containing three white balls and five blue balls. Find the probability that two or three of the balls are white.
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P(A or B) = P(A) + P(B) - P(A and B)
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P(2 or 3 white) = P(2 white) + P(3 white) -0
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P(2 white and 3 blue) = [3C2*5C3]/8C5 = (3*10)/56 = 30/56
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P(3 white and 2 blue) = [3C3*5C2]/8C5 = (1*10)/56 = 10/56
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Ans: P(2 white or 3 white) = (30+10)/56 = 40/56
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Cheers,
Stan H.
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