Preliminary Data Analyses Indicates That Use of a Paired T-Test $\mathrm { H } _ { 0 } : \mu _ { 1 } = \mu _ { 2 }$

question 25

Essay

Preliminary data analyses indicates that use of a paired t-test is reasonable. Perform the hypothesis test by using eitherthe critical-value approach or the P-value approach as indicated. Assume that the null hypothesis is $\mathrm { H } _ { 0 } : \mu _ { 1 } = \mu _ { 2 }$
-Ten different families are tested for the number of gallons of water a day they use before and after viewing a conservation video. The results are shown below. $\begin{array} { l c c c c c c c c c c } \text { Before } & 33 & 33 & 38 & 33 & 35 & 35 & 40 & 40 & 40 & 31 \\ \hline \text { After } & 34 & 28 & 25 & 28 & 35 & 33 & 31 & 28 & 35 & 33 \end{array}$ At the 5% significance level, do the data provide sufficient evidence to conclude that the mean amount of water use after the viewing differs from the mean amount of water use before the viewing? Use the critical-value approach.

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Definitions:

Financial Reports

Documents that contain detailed information about a company's financial health, performance, and cash flow over a specific period.

Prepaid Item

An expense paid in advance and recorded as an asset until it is actually used or consumed.

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Financial records established at the conclusion of an accounting term to assign earnings and costs to the period they truly belong.

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The cost incurred by a business or individual for purchasing insurance policies to protect against potential losses or liabilities.