# Question

a. In a random sample of 500 observations drawn from a normal population, the sample mean and sample standard deviation were calculated as x̄ = 350 and s = 100. Estimate the population mean with 99% confidence.

b. Repeat part (a) assuming that you know that the population standard deviation is σ = 100.

c. Explain why the interval Estimates were virtually identical.

b. Repeat part (a) assuming that you know that the population standard deviation is σ = 100.

c. Explain why the interval Estimates were virtually identical.

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