Answer:
Now we have everything in order to replace into formula (1):
Step-by-step explanation:
Information given
represent the sample mean
population mean (variable of interest)
s=2.75 represent the sample standard deviation
n=10 represent the sample size
Confidence interval
The confidence interval for the mean is given by the following formula:
(1)
The degrees of freedom are given by:
The Confidence is 0.90 or 90%, the significance is and
, and the critical vaue would be
Now we have everything in order to replace into formula (1):