<PRE><B>Question 417921</B>
In an urn there are 5 blue, 6 red and 4 green balls. 
Three balls are randomly drawn from the urn without replacement. 
What is the probability of drawing only two colors from the urn?
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There ae 5C3  = 10 all blue
There are 6C3 = 20 all red
There are 4C3 = 4 all green
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There are 5*6*4 = 120 that are all three colors.---
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There are a total of 15C3  = 455 sets of three.
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# of sets with 2 colors = 455-[10+20+4+120] = 455-154 = 301
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P(drawing a set with only 2 colors) = 301/455
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Cheers,
Stan H.
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