Answer: (3.46, 3.62)
Step-by-step explanation:
The formula to find the confidence interval for population mean is given :-
, where n = sample size.
= Two-tailed t-value for significance level of
and degree of freedom df= n-1.
= sample standard deviation.
As per given , we have
mm
s= 0.20 mm
n= 25
Significance level
Since population standard deviation is not given , it means the given problem has t- distribution.
Two-tailed t-value for significance level of and degree of freedom df= 24:
95% Confidence interval for population mean:
Hence, the 95% two-sided confidence interval for the mean glass thickness = (3.46, 3.62)
