Question 1116050
 A box contains 4 ​red, 3 white and 4 green balls. Two balls are drawn out of the box in succession without replacement. What is the probability that both balls are the same​ color? 
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# of same-colored balls:: 4C2+3C2+4C2 = 6+3+6 = 15
# of random pairs:: 11C2 = 55
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P(both same color) = 15/55 = 3/11
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Cheers,
Stan H.
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