TABLE 10-14
a Problem with a Telephone Line That

question 124

Multiple Choice

TABLE 10-14
A problem with a telephone line that prevents a customer from receiving or making calls is disconcerting to both the customer and the telephone company. The data on samples of 20 problems reported to two different offices of a telephone company and the time to clear these problems (in minutes) from the customers' lines are collected. Below is the Excel output to see whether there is evidence of a difference in the mean waiting time between the two offices assuming that the population variances in the two offices are not equal.
$$\begin{array}{l}\text { t- Test: Two- Sample Assuming Unequal Variances }\\\begin{array} { l r r } \hline & \text { Office 1 } & \text { Office 2 } \\\hline \text { Mean } & 2214 & 2.0115 \\\text { Variance } & 2.951657 & 3.57855 \\\text { Observations } & 20 & 20 \\\text { Hypothesized Mean Difference } & 0 & \\\mathrm { df } & 38 & \\\mathrm { t } \text { Stat } & 0.354386 & \\\mathrm { P } ( \mathrm { T } < = \mathrm { t } ) \text { one- tail } & 0.362504 & \\\mathrm { t } \text { Critical one- tail } & 1.685953 & \\\mathrm { P } ( \mathrm { T } < = \mathrm { t } ) \text { two- tail } & 0.725009 & \\\mathrm { t } \text { Critical two- tail } & 2.024394 &\end{array}\end{array}$$
-Referring to Table 10-14, what is(are) the critical value(s) of the relevant hypothesis test if the level of significance is 0.10?

• A) 1.6860
• B) ±2.0244
• C) 2.0244
• D) ±1.6860

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Definitions:

Conversion Efficiencies

The ratio of useful energy output to total energy input in a system, measuring how effectively energy resources are converted and used.

Biomass Fuels

Renewable energy derived from organic materials such as wood, waste, and alcohol fuels used for generating electricity or producing heat.

R-value

A measure of thermal resistance, indicating the effectiveness of insulation materials in preventing heat transfer.

Canadian Government

The federal administration of Canada which operates under a parliamentary system within a constitutional monarchy.