SOLUTION: There are 12 pens in a pack. 7 of the pens are blue and 5 of the pens are red. Three pens are picked at random from the pack without replacement. Work out the probability that exac

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Question 778401: There are 12 pens in a pack. 7 of the pens are blue and 5 of the pens are red. Three pens are picked at random from the pack without replacement. Work out the probability that exactly one of the pens is red and two are blue.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
There are 12 pens in a pack. 7 of the pens are blue and 5 of the pens are red. Three pens are picked at random from the pack without replacement. Work out the probability that exactly one of the pens is red and two are blue.
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# of ways to succeed:: 5C1*7C2 = 5*21 = 105
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# of possible outcomes:: 12C3 = 220
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P(1 red/2blue without replacement) = 105/220 = 0.4773
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Cheers,
Stan H.
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