SOLUTION: A sample of 15 randomly selected students has a grade point average of 2.86 with a deviation of 0.78. Construct a 90% confidence interval for the population mean.

Question 275274: A sample of 15 randomly selected students has a grade point average of 2.86 with a deviation of 0.78. Construct a 90% confidence interval for the population mean.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
A sample of 15 randomly selected students has a grade point average of 2.86 with a deviation of 0.78. Construct a 90% confidence interval for the population mean.
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sample mean = 2.86
standard error = E = 1.645*0.78/sqrt(15) = 0.3313
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90% CI: 2.86 - 0.3313 < u < 2.86+0.3313
90% CI:2.5287 < u < 3.1913
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Cheers,
Stan h.

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