Answer:
And we are 95% confident that the true mean of chloride concentration is between 0.375 and 0.377 cc/ cubic meter
Step-by-step explanation:
Data provided
represent the sample mean for the chloride concentration
population mean (variable of interest)
s=0.0012 represent the sample standard deviation
n=15 represent the sample size
Confidence interval
The confidence interval for the mean is given by the following formula:
(1)
Since we need to find the critical value first we need to begin finding the degreed of freedom
The Confidence is 0.95 or 95%, the significance would be and
, and the critical value for this case with a t distribution with 14 degrees of freedom is
And the confidence interval is:
And we are 95% confident that the true mean of chloride concentration is between 0.375 and 0.377 cc/ cubic meter
