Show all work on this paper. 1. Thompson and Thompson is a steel bolts manufactu
ID: 2932791 • Letter: S
Question
Show all work on this paper. 1. Thompson and Thompson is a steel bolts manufacturing company. Their current steel bolts have a mean diameter of 128 millimeters, and a standard deviation of 8. If a random sample of 31 steel bolts is selected, what is the probability that the sample mean would differ from the population mean by more than 0.9 millimeters? Round your answer to four decimal places. 2. Thompson and Thompson is a steel bolts manufacturing company. heir current steel bolts have a mean diameter of 141 millimeters, and a standard deviation of 7. If a random sample of 39 steel bolts is selected, what is the probability that the sample mean would be greater than 141.4 millimeters? Round your answer to four decimal places.Explanation / Answer
Hi , please don't post assignment question. You could break down the assignment into individual questions and then post them.
1.
We change the X' distribution to Z distribution by using the below normal params:
Mean = 128 mm
Stdev = 8 mm
n = 31
P( |Musample-Mupop| > 0.9)
= P( |Z| > 0.9/(8/sqrt(31))
= P(|Z|> .6264)
= 2*(1-.7324) = .5352