Question
Table 15 lists average annual telephone expenditures (in dollars) per consumer unit on residential phone service and cellular phone service, and the figure contains a scatter plot and regression line for each data set.(A) Interpret the slope of each model.(B) Predict (to the nearest dollar) the average annual residential and cellular expenditures in $2015 .$(C) Would the linear regression models give reasonable predictions for the year $2025 ?$ Explain.
Step 1
The slope is measured in dollars per year. If the slope is positive, it means the average annual expenditure is increasing each year. If the slope is negative, it means the average annual expenditure is decreasing each year. Show more…
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