To Estimate the Average Annual Expenses of Students on Books

question 81

Multiple Choice

To estimate the average annual expenses of students on books and class materials, a sample of size 36 is taken. The sample mean is $850 and the sample standard deviation is $54. A 99 percent confidence interval for the population mean is:

• A)$823.72 to $876.28
• B)$832.36 to $867.64
• C)$826.82 to $873.18
• D)$825.48 to $874.52

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Definitions:

Contribution Margin Ratio

A financial metric that measures the proportion of revenue that exceeds variable costs, indicating how much revenue contributes towards covering fixed costs and generating profit.

Variable Expenses

Costs that change in proportion to the level of activity or volume of output in a business.

Fixed Expenses

Costs that do not change in total regardless of the level of production or sales activity, such as rent and salaries.

Net Income

The total profit or loss of a company after all expenses, including taxes and operating costs, have been subtracted from revenues.