A Credit Union Took a Random Sample of 40 Accounts $90 \%$

question 17

Multiple Choice

A credit union took a random sample of 40 accounts and yielded the following $90 \%$ confidence interval for the mean checking account balance at the institution:
$\$ 2183 < \mu$ (balance) $< \$ 3828$ .

• A) If we took random samples of checking accounts at this credit union, about nine out of ten of them would produce this confidence interval.
• B) We are \(90 \%\) confident that the mean checking account balance at this credit union is between \(\$ 2183\) and \(\$ 3828\), based on this sample.
• C) We are \(90 \%\) confident that the mean checking account balance in the U.S. is between \(\$ 2183\) and \$3828.
• D) About 9 out of 10 people have a checking account balance between \(\$ 2183\) and \(\$ 3828\).
• E) We are \(90 \%\) sure that the mean balance for checking accounts in the sample was between \(\$ 2183\) and \(\$ 3828\)

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Definitions:

Contribution Margin

The contribution margin represents the portion of sales revenue that is not consumed by variable costs and is available to cover fixed costs, contributing to profit.

Fixed Cost

A fixed cost is a cost that does not change with an increase or decrease in the amount of goods or services produced or sold.

Hard Rationing

A situation where capital is not available to a company under any circumstances, often due to economic conditions or poor company performance.

Soft Rationing

A situation where a company limits the amount of funding or capital it allocates to new or ongoing projects, often due to internal policy decisions.