Lazurus Steel Corporation produces iron rods that are supposed to be 30 inches long. The machine that makes these rods does not produce each rod exactly 30 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 30 inches. The standard deviation of the lengths of all rods produced on this machine is always equal to 0.3 inch. The quality control department takes a sample of 21 such rods every week, calculates the mean length of these rods, and makes a 97% confidence interval for the population mean. If either the upper limit of this confidence interval is greater than 30.10 inches or the lower limit of this confidence interval is less than 29.9 inches, the machine is stopped and adjusted. A recent sample of 21 rods produced a mean length of 30.01 inches. Based on this sample, will you conclude that the machine 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 is to inches. The machine an adjustment.

Lazurus Steel Corporation produces iron rods that are supposed to be 30 inches long. The machine that makes these rods does not produce each rod exactly 30 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 30 inches. The standard deviation of the lengths of all rods produced on this machine is always equal to 0.3 inch. The quality control department takes a sample of 21 such rods every week, calculates the mean length of these rods, and makes a 97% confidence interval for the population mean. If either the upper limit of this confidence interval is greater than 30.10 inches or the lower limit of this confidence interval is less than 29.9 inches, the machine is stopped and adjusted. A recent sample of 21 rods produced a mean length of 30.01 inches. Based on this sample, will you conclude that the machine 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 is to inches. The machine an adjustment.

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Description: Lazurus Steel Corporation produces iron rods that are supposed to be 30 inches long. The machine that makes these rods does not produce each rod exactly 30 inches long. The lengths of the rods vary slightly. It is known that when the machine is work

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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