# Question

A sociologist found that in a sample of 50 retired men, the average number of jobs they had during their lifetimes was 7.2. The population standard deviation is 2.1.

a. Find the best point estimate of the mean.

b. Find the 95% confidence interval of the mean number of jobs.

c. Find the 99% confidence interval of the mean number of jobs.

d. Which is smaller? Explain why.

a. Find the best point estimate of the mean.

b. Find the 95% confidence interval of the mean number of jobs.

c. Find the 99% confidence interval of the mean number of jobs.

d. Which is smaller? Explain why.

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