SOLUTION: An electrical company takes 120 hours with a standard deviation of 25 hours to wire a build complex. What is probability that the same company will take at least 115 hours to do th

Question 787888: An electrical company takes 120 hours with a standard deviation of 25 hours to wire a build complex. What is probability that the same company will take at least 115 hours to do the same job?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
An electrical company takes 120 hours with a standard deviation of 25 hours to wire a build complex. What is probability that the same company will take at least 115 hours to do the same job?
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z(115) = (115-120)/25 = -1/5
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P(x >= 115) = P(z >= -1/5) = 0.5793
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Cheers,
Stan H.
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