<PRE><B>Question 390780</B>
 A school has two backup generators having probabilities of 0.9 and 0.95, respectively , of operating in case of power outage. find the probability that at least one backup generator operates during a power outage
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P(both fail) = 0.1*0.05 = 0.005
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P(at least one operates) = 1- P(both fail) = 1-0.005 = 0.995
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Cheers,
Stan H.
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F 0.855
G 0.89
H 0.95
J 0.995 

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