A Machine Has Been Designed to Make Nails Which Are

question 107

Multiple Choice

A machine has been designed to make nails which are 8cm long with a standard deviation of 0.15cm.A sample of 48 nails is selected periodically to assess if the length is too variable from the standard of 8cm.From the sample of 48 nails,the mean is found to be 7.983cm.Assume the lengths are normally distributed and the standard deviation is known to be 0.15cm.Compute the 95% confidence interval for the population mean nail length.

• A)[7.947,8.019]
• B)[7.941,8.025]
• C)[7.933,8.033]
• D)[7.955,8.011]
• E)[7.916,8.050]

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Definitions:

Percentage Increase

A measure of the degree to which a quantity has grown compared to its previous value, expressed as a percentage.

Horizontal Analysis

Amounts of items compared on the same line of comparative financial reports. Horizontal analysis can also be in the form of a trend analysis.

Trend Percentage

A financial analysis tool that shows how a financial statement item changes over time, often used to spot patterns or trends.