Question 561912
In a scientific study there are 12 guinea pigs, 5 of which are pregnant. If 3 are selected at random without replacement, find the probability that none are pregnant. Enter your answer as a fraction. 
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Binomial Problem with n = 3 and p(not pregnant) = 7/12
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P(x = 0) = 3C3*(7/12)^3*(5/12)^0 = (7/12)^3 = 0.1985
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Cheers,
Stan H.
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