Question

Pvc pipe is manufactured with a mean diameter of 1.01 inch and a standard deviation of 0.003 inch. find the probability that a random sample of n = 9 sections of pipe will have a sample mean diameter greater than 1.009 inch and less than 1.012 inch

Answer 1

Answer: 7.517 inches

Hope I was helpful! (:

Answer 2

The probability that the sample mean is within 2 standard deviations on the high side and 1 standard deviation on the low side is about 0.8186.