Question 417917: please help me solve this question.
there are three urns, A B C. In A there are 6 blue and 4 green balls, In B there are 2 blue and 8 green balls, In C there are 5 blue and 5 green balls. 3 balls are then randomly drawn from each urn without replacement. what is the probability of drawing 8 balls of the same color?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! there are three urns, A B C. In A there are 6 blue and 4 green balls, In B there are 2 blue and 8 green balls, In C there are 5 blue and 5 green balls. 3 balls are then randomly drawn from each urn without replacement.
what is the probability of drawing 8 balls of the same color?
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Total balls 30
Pick a color: 2 ways
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Blues:
A has 6
B has 2
C has 5
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Pick 8 blue balls: A3/B2/C3 :
6C3*2C2*5C3 = 20*1*10 = 200 ways
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Green:
A has 4
B has 8
C has 5
Pick 8 green :
4C3*8C3*5C2 = 4*56*10 = 2240 ways
or 8C3*5C3*4C3 = 56*10*4 = 2240 = ways
or 5C3*4C3*8C2 = 10*4*28 = 1120 = ways
Total 8 green = 5600
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Total # of ways to get 8blue or 8 green = 5800
Total # of sets of 3/3/3
(10C3)^3 = 120^3 = 1728000
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P(8 blue or 8 green) = 5800/1728000 = 0.003356
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Comment:
Don't take all this as Gospel truth unless
you agree with the approach and the arithmetic.
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Cheers,
Stan H.
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