SOLUTION: There a 100 ducks in a pond. 15 of them have red dots on them. If three ducks are randomly picked. What is the probability that 2 of them are ducks with a red dot? Once a duck

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Question 615197: There a 100 ducks in a pond. 15 of them have red dots on them. If three ducks are randomly picked. What is the probability that 2 of them are ducks with a red dot? Once a duck is picked, it does not go back in the pond.
Here is what I tried.
15/100 X 14/99
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
There a 100 ducks in a pond. 15 of them have red dots on them. If three ducks are randomly picked. What is the probability that 2 of them are ducks with a red dot? Once a duck is picked, it does not go back in the pond.
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# of triples with 2 red and and 1 not red.
15C2*85 = 105*85 = 8925
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# of random triples = 100C3 = 161700
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P(2 red and 1 not red) = 8925/161700 = 0.0552
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Cheers,
Stan H.
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