Provide an Appropriate Response $95 \%$ Confidence Interval for the Population Mean

question 52

Multiple Choice

Provide an appropriate response.
-Construct a $95 \%$ confidence interval for the population mean, $\mu$ . Assume the population has a normal distribution. A sample of 20 part-time workers had mean annual earnings of $\$ 3120$ with a standard deviation of $\$ 677$ .

• A) \(( \$ 2803 , \$ 3437 )\)
• B) \(( \$ 1324 , \$ 1567 )\)
• C) \(( \$ 2135 , \$ 2567 )\)
• D) \(( \$ 2657 , \$ 2891 )\)

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Definitions:

Contribution Margin

The contribution margin is the sales revenue minus the variable costs. It shows how much revenue contributes to covering the fixed costs and generating profit.

Fixed Corporate Costs

Expenses that do not vary with production levels, including salaries of executives, rent, and insurance.

Fixed Costs

Expenses that do not change with the level of output or sales over a specific period, such as rent, salaries, or insurance.

Financial Advantage

The gain or benefit obtained in financial terms, often seen in the context of investments or business operations.