A Car Mechanic Is Thinking of Guaranteeing Customers That an Oil

question 139

Essay

A car mechanic is thinking of guaranteeing customers that an oil change will take no more than 15 minutes with a 99.73% confidence level.He takes a few samples of size 5 and finds the process mean to be 13 minutes with a standard deviation of .2 minutes and average sample range of 1.2 minutes.Find the , ,and values and use them to compute the upper and lower limits for an x-bar chart.Use the upper limit to determine if the mechanic can offer a 15 minute guarantee.Assume the mechanic plots the samples on the x-bar control chart and finds the process is in control,is there anything else the mechanic is missing to ensure the process is in control?

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Definitions:

Legal Agreement

A binding contract between two or more parties that is enforceable by law.

U.S. Clothing Firm

A U.S. Clothing Firm is a business enterprise located in the United States that specializes in the design, production, and sale of clothing and apparel items.

Direct Ownership

A situation where an individual or entity has full control and claim over an asset or property, without any intermediaries.

Contract Manufacturing

The outsourcing of certain production activities to third-party companies, often to save costs or leverage specialized capabilities.