SOLUTION: A simple random sample of 101 light bulbs had a mean life of 576 hours with a standard devation of 34 hours. construct a 90 percent confidence interval for the mean life of all lig

Question 435211: A simple random sample of 101 light bulbs had a mean life of 576 hours with a standard devation of 34 hours. construct a 90 percent confidence interval for the mean life of all light bulbs of this type.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
A simple random sample of 101 light bulbs had a mean life of 576 hours with a standard devation of 34 hours.
Construct a 90 percent confidence interval for the mean life of all light bulbs of this type.
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x-bar = 576
ME = zs/sqrt(101) = 1.645*34/sqrt(101) = 5.5652
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90%CI: 576-5.5652 < u < 576+5.5652
90%CI: 570.43 < u < 581.57
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Cheers,
Stan H.
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