SOLUTION: a bag contains 10 red balls 15 green balls and 5 purple balls if two balls are chosen at random without replacement what is the probability that both of them are the same color?

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Question 1034065: a bag contains 10 red balls 15 green balls and 5 purple balls if two balls are chosen at random without replacement what is the probability that both of them are the same color?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
a bag contains 10 red balls 15 green balls and 5 purple balls if two balls are chosen at random without replacement what is the probability that both of them are the same color?
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# of same-color pairs:: 10C2 + 15C2 + 5C2 = 45+95+10 = 150
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# of random pairs:: 30C2 = 435
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P(same-color pills) = 150/435 = 0.345
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Cheers,
Stan H.
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