Ans:
Standard error of mean=800/sqrt(64)=100
Sample mean=4000
critical z value for 97% Confidence level is 2.17
97% confidence interval for mean annual earnings
=4000+/-2.17*100
=4000+/-217
=(3783, 4217)
to. Cóllege students annual earnings are hormally distributed with standard deviation σ $800. If the mean...
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