Question

A simple random sample of size n is drawn from a population that is normally distributed. The sample​ mean, x overbar​, is found to be 105​, and the sample standard​ deviation, s, is found to be 10. ​(a) Construct a 95​% confidence interval about mu if the sample​ size, n, is 26. ​(b) Construct a 95​% confidence interval about mu if the sample​ size, n, is 20. ​(c) Construct an 80​% confidence interval about mu if the sample​ size, n, is 26. ​(d) Could we have computed the confidence intervals in parts​ (a)-(c) if the population had not been normally​ distributed?

Answer 1