<PRE><B>Question 344440</B>
let N=event the chosen factory is a non violator
each outcomes probability is dependent on what was selected previously
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P(selecting 6 at random and getting none of the violators)=P(NNNNNN)
= (16/20)*(15/19)*(14/18)*(13/17)*(12/16)*(11/15) = 0.2066
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this probability could also be written as

C(4,0)*C(16,6)/C(20,6)  basically # ways choosing 0 of the 4 violators times # ways of choosing 6 nonviolators out of 16 nonviolators divided by the # ways of selecting 6 factories out of 20

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