A sample of size n = 89 has sample mean x̄ = 87.2 and sample standard...
A sample of size n = 89 has sample mean x̄ = 87.2 and sample standard deviation s = 5.3.
- Construct a 95% confidence interval for the population mean ?.
-
b. If the confidence level were 99%, would the confidence interval be narrower or wider?
( I am having trouble figuring out how the t-critical value of 1.963 is calculated as the answer for (a) and t-critical value for b) It does not make sense to me. Can someone explain?
Homework Answers
Solution:-
a) 95% Confidence interval for the mean = (86.084,88.316)
b) 99% Confidence interval be wider.
99% Confidence interval for the mean = (85.721,88.679)
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