A sample is selected to find a 90% confidence interval for the average starting salary. Here...

A sample is selected to find a 90% confidence interval for the average starting salary. Here are the sample statistics: n = 31, x ̄ = $43, 780, s = $1, 600.

a). Find the t− score used in the calculation of the confidence interval.

b). Build a 90% confidence interval for the mean starting salary.

c). Based on the result of part b), could we make a conclusion that the mean staring salary is below $45, 000? Explain your reason.

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orchestra answered 10 months ago

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