SOLUTION: Construct a confidence interval for the population mean given that the sample size is 120, the sample mean is 86.1, and sigma is 17, and the desired confidence is 90%. Choose the c

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Question 1056720: Construct a confidence interval for the population mean given that the sample size is 120, the sample mean is 86.1, and sigma is 17, and the desired confidence is 90%. Choose the correct interval from the following:

(63.5, 68.7)
(73.5, 78.7)
(83.5, 99.7)
(83.5, 88.7)

Answer by Boreal(15235)   (Show Source): You can put this solution on YOUR website!
the interval width is z(0.95)*sigma/sqrt(n)
That is 1.645*17/sqrt(120)=2.55
The interval is (83.55,88.65)

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