The population of lengths of aluminum-coated steel sheets is normally distributed with a mean of 30.05 inches and a standard deviation of .3 inches. What is the probability that the average length of a steel sheet from a sample of 9 steel sheets is more than 29.95 inches long?

Question

Quizplus · Accepted Answer

P[z > (29.95 − 30.05)/(.3/)] = P(z > −1) = 1.00 − .1587 = .8413

The Population of Lengths of Aluminum-Coated Steel Sheets Is Normally