A Random Sample of Records of Electricity Usage of Homes $\mathrm { R } ^ { 2 }$

question 7

Multiple Choice

A random sample of records of electricity usage of homes gives the amount of electricity used and size (in square feet) of 135 homes.A regression to predict the amount of electricity used (in kilowatt-hours) from size has an R-squared of 71.3%.The residuals plot indicated that a linear model is appropriate.Write a sentence summarizing what $\mathrm { R } ^ { 2 }$ says about this regression.

• A)Size differences explain 28.7% of the variation in electricity usage.
• B)Differences in electricity usage explain 71.3% of the variation in the size of house.
• C)Size differences explain 71.3% of the variation in the number of homes.
• D)Size differences explain 71.3% of the variation in electricity usage.
• E)Differences in electricity usage explain 28.7% of the variation in the number of house.

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Definitions:

Inches

A unit of measurement in the imperial and United States customary systems, equivalent to 1/12 of a foot.

Kilometers

A unit of length in the metric system equal to 1,000 meters, commonly used to measure distances between geographical locations.

Miles

A unit of distance measurement in the Imperial system, equal to 1.609 kilometers.

Kilometers Per Hour (Kmph)

A unit of speed or velocity in the metric system, measuring the number of kilometers traveled in one hour.