Question

In: Statistics and Probability

Below you are given ages that were obtained by taking a random sample of 6 undergraduate...

Below you are given ages that were obtained by taking a random sample of 6 undergraduate students. Assume the population has a normal distribution.

40

42

43

39

37

39

a.

What is the point estimate of μ?

b.

Determine the standard deviation.

c.

Construct a 90% confidence interval for the average age of undergraduate students.

d.

Construct a 99% confidence interval for the average age of undergraduate students.

e.

Discuss why the 99% and 90% confidence intervals are different.

Solutions

Expert Solution

a) 40

b) 2.1909

c)

d)

e) both are different because 99% confidence interval is wider than 90% confidence interval.

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