# Question: The standard deviation for a population is 15 3

The standard deviation for a population is σ = 15.3. A sample of 36 observations selected from this population gave a mean equal to 74.8.

a. Make a 90% confidence interval for µ.

b. Construct a 95% confidence interval for µ.

c. Determine a 99% confidence interval for µ.

d. Does the width of the confidence intervals constructed in parts a through c increase as the confidence level increases? Explain your answer.

a. Make a 90% confidence interval for µ.

b. Construct a 95% confidence interval for µ.

c. Determine a 99% confidence interval for µ.

d. Does the width of the confidence intervals constructed in parts a through c increase as the confidence level increases? Explain your answer.

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