4. (5 points) Let Y be the mean of a (random) sample of size n from a population with a normal
distribution with mean and variance 9. Find the smallest integer n such that (Y1,Y+1) is a 90%
confidence interval..
4. (5 points) Let Y be the mean of a (random) sample of size n from a.pdf
1. 4. (5 points) Let Y be the mean of a (random) sample of size n from a population with a normal
distribution with mean and variance 9. Find the smallest integer n such that (Y1,Y+1) is a 90%
confidence interval.