SOLUTION: 4. A bag of 10 marbles contains 3 red marbles and 7 blue marbles. If two marbles are selected at random, what is the probability that at least one marble is blue?

Algebra ->  Probability-and-statistics -> SOLUTION: 4. A bag of 10 marbles contains 3 red marbles and 7 blue marbles. If two marbles are selected at random, what is the probability that at least one marble is blue?       Log On


   



Question 723966: 4. A bag of 10 marbles contains 3 red marbles and 7 blue marbles. If two marbles are selected at random, what is the probability that at least one marble is blue?

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A bag of 10 marbles contains 3 red marbles and 7 blue marbles. If two marbles are selected at random, what is the probability that at least one marble is blue?
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P(at least one blue) = 1 - P(no blue)
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= 1 - [3C2/10C2]
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= 1 - 3/45
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= 1 - (1/15)
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= 14/15
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Cheers,
Stan H.
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