Author Question: What sample size should be used if we would like to estimate the mean age of the individuals who ... (Read 90 times)

LCritchfi · **on:** Jul 24, 2018

What sample size should be used if we would like to estimate the mean age of the individuals who are attend a university with a 95 confidence interval that has a width of at most 5 years? Assume the population is normally distributed with a standard deviation of 4.2 years.

a.The sample size should be 10.
b.The sample size should be 19.
c.The sample size should be 11.

d.The sample size should be 8.

Question 2

Which of the following is the correct formula for a

confidence interval for

when both

and

are estimated?

a.

with df = n - 1
b.

with df = n - 1
c.

with df = n - 1