Determine The $95 \%$ Confidence Interval of the True Difference in the Means

question 48

Multiple Choice

Determine the $95 \%$ confidence interval of the true difference in the means. A sociologist wants to determine if the life expectancy of people in Africa is less than the life expectancy of people in Asia. The data obtained is shown in the table below. Use $\alpha =$$0.05$ .
$\begin{array}{|l|l|l|}\hline & \text { Africa } & \text { Asia } \\\hline \overline{\bar{X}} & 55.3 & 65.2 \\\hline \sigma & 8.1 & 9.3 \\\hline n & 53 & 42 \\\hline\end{array}$

• A) \(- 12.16 < \mu _ { 1 } - \mu _ { 2 } < - 686\)
• B) \(- 13.46 < \mu _ { 1 } - \mu _ { 2 } < - 6.34\)
• C) \(- 11.35 < \mu _ { 1 } - \mu _ { 2 } < - 7.58\)
• D) \(- 16.33 < \mu _ { 1 } - \mu _ { 2 } < - 5.98\)

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Definitions:

Fixed Cost

Costs that do not vary with the level of production or sales, such as rent, insurance, and salaries of permanent staff.

Relevant Range

The range of activity within which the assumptions about fixed and variable cost behavior are valid.

Activity Level

A measure of the volume of production or operations, which can affect the costs and efficiency of manufacturing processes.

Factory Overhead

Refers to all indirect manufacturing costs, including but not limited to utilities, maintenance, and depreciation related to the production process.