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In: Statistics and Probability

The age distribution of students in a graduate program is approximately Normal with un- known mean...

The age distribution of students in a graduate program is approximately Normal with un- known mean μ and standard deviation σ = 5. You sample 24 individuals from this population and calculate the sample mean 25.0.

(a) Calculate the 95% confidence interval for the mean based on these data. Interpret your interval.

(b) Calculate the 99% confidence interval for the data

(c) Is the 99% confidence intervals wider than the 95% confidence interval? Why?

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