SOLUTION: 2 marbles are selected at random from an urn which contain 4 white and 8 black marbles. what is the probability that both marbles will be white?

Question 473225: 2 marbles are selected at random from an urn which contain 4 white and 8 black marbles. what is the probability that both marbles will be white?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
2 marbles are selected at random from an urn which contain 4 white and 8 black marbles. what is the probability that both marbles will be white?
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# of ways to select 2 white marbles: 4C2 = 6
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# of ways to select 2 marbles randomly: 12C2 = 66
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P(2 white) = 6/66 = 1/11
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Cheers,
Stan H.
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