Lazurus Steel Corporation produces iron rods that are supposed to be 37 inches long. The machine that makes these rods does notproduce each rod exactly 37 inches long. The lengths of the rods vary slightly. It is known that when the machine is working properly,the mean length of the rods made on this machine is 37 inches. The standard deviation of the lengths of all rods produced on thismachine is always equal to 0.2 inch. The quality control department takes a sample of 20 such rods every week, calculates the meanlength of these rods, and makes a 97% confidence interval for the population mean. If either the upper limit of this confidence intervalis greater than 37.05 inches or the lower limit of this confidence interval is less than 36.95 inches, the machine is stopped andadjusted. A recent sample of 20 rods produced a mean length of 37.08 inches. Based on this sample, will you conclude that themachine needs an adjustment? Assume that the lengths of all such rods have a normal distribution.Round your answers to two decimal places.The confidence interval isitoiinches.The machinean adjustment.

Answered: adjusted. A recent sample of 20 rods…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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