Question 274781
a bag contains 6 green,5 yellow and 7 white balls are drawn at random from the box.find the probability that among the balls drawn there is one ball of each colour
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How many balls are drawn? 
Are the balls replaced before the next draw?
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If it's 3, without replacement, then:
the chance of green is 6/18
the chance of yellow is 5/17, and
the chance of white is 7/16
--> (1/3)*(5/17)*(7/16) = 35/816
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Other results are possible with different constraints.