Answer:
The confidence interval is given by (49.94, 59.26)
Explanation:
Info given
represent the sample mean
population mean (variable of interest)
s=9.2 represent the sample standard deviation
n=48 represent the sample size
Part a
The confidence interval for the mean is given by the following formula:
(1)
The degrees of freedom are given by:
The Confidence is 0.999 or 99.9%, and the significance is
and
, and the critical value would be
And replacing we got:
The confidence interval is given by (49.94, 59.26)