Use the Given Degree of Confidence and Sample Data to Construct

question 26

Multiple Choice

Use the given degree of confidence and sample data to construct a confidence interval for the population mean µ. Assume that the population has a normal distribution.
-The mean replacement time for a random sample of 20 washing machines is 10.2 years and the standard deviation is 2.6 years. Construct a 99% confidence interval for the standard deviation, ?, of the replacement times of all washing machines of this type.

• A) \(1.8 \mathrm { yr } < \sigma < 4.9 \mathrm { yr }\)
• B) \(1.8 \mathrm { yr } < \sigma < 5.5 \mathrm { yr }\)
• C) \(1.8 \mathrm { yr } < \sigma < 4.3 \mathrm { yr }\)
• D) \(1.9 \mathrm { yr } < \sigma < 4.1 \mathrm { yr }\)

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Definitions:

Consumption of Services

The action of using services offered in the economy, which can include healthcare, education, and entertainment among others.

Big State University

A hypothetical or generic large public university often used in academic examples.

Tuition

The fee charged for instruction or education, typically by an educational institution such as a school or university.

Disposable Personal Income

Funds available to families for saving or spending after subtracting income taxes.