Ten Different Families Are Tested for the Number of Gallons

question 14

Multiple Choice

Ten different families are tested for the number of gallons of water a day they use before and after viewing a conservation video.Construct a 90% confidence interval for the mean of the differences.

$\begin{array}{|l|l|l|l|l|l|l|l|l|l|l|}\hline \text { Before } & 33 & 33 & 38 & 33 & 35 & 35 & 40 & 40 & 40 & 31 \\\hline \text { After } & 34 & 28 & 25 & 28 & 35 & 33 & 31 & 28 & 35 & 33 \\\hline\end{array}$

• A) \(( 1.8,7.8 )\)
• B) \(( 2.5,7.1 )\)
• C) \(( 3.8,5.8 )\)
• D) \(( 1.5,8.1 )\)
• E) \(( 2.1,7.5 )\)

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Definitions:

Moving Average Forecast

A method used in time series analysis to smooth out short-term fluctuations and highlight longer-term trends or cycles.

Observable Trend

A pattern, change, or movement in data or events that can be detected and analyzed through observation.

Seasonality

Refers to periodic fluctuations in business or data that recur in a predictable pattern based on the time of year.

Causal Forecasting Methods

Predictive techniques that assume a cause-and-effect relationship between the variable forecasted and one or more independent variables.