A Precision Control Engineer Is Interested in the Mean Length

question 28

Essay

A precision control engineer is interested in the mean length of tubing being cut automatically by machine.It is known that the standard deviation in the cutting length is 0.15 feet.A sample of 60 cut tubes yields a mean length of 12.15 feet.This sample will be used to obtain a 99% confidence interval for the mean length cut by machine.
a.What is the zα _{/ 2} value to use in obtaining the confidence interval?
b.Develop the 99% confidence interval for μ.

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Definitions:

Unionize

The act of forming or joining a union to collectively bargain for improved working conditions, wages, and benefits.

Open Shop Movement

Advocacy for workplaces where union membership is not a condition of employment, allowing employees the choice to join or not join a union.

Private Sector Union Density

Refers to the proportion of workers in the private sector who are members of a union, indicating the level of unionization within private industry.

Labor Movement

A social movement aiming to improve conditions for workers, focusing on rights, wages, and working conditions.