# Question: When calculating a confidence interval for the population mean

When calculating a confidence interval for the population mean µ with a known population standard deviation σ, describe the effects of the following two changes on the confidence interval:

(1) Doubling the sample size,

(2) Quadrupling (multiplying by 4) the sample size. Give two reasons why this relationship does not hold true if you are calculating a confidence interval for the population mean µ with an unknown population standard deviation.

(1) Doubling the sample size,

(2) Quadrupling (multiplying by 4) the sample size. Give two reasons why this relationship does not hold true if you are calculating a confidence interval for the population mean µ with an unknown population standard deviation.

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