Concept explainers
Regression and Predictions. Exercises 13–28 use the same data sets as Exercises 13–28 in Section 10-2. In each case, find the regression equation, letting tire first variable be the predictor (x) variable. Find the indicated predicted value by following the prediction procedure summarized in Figure 10-5.
25. Gas Prices One gas station not included in the table below had a listed price of $2.78 for regular gas. Find the best predicted price of premium gas at this station. Is the result close to the actual price of $2.93 for premium gas?
Regular | 2.77 | 2.77 | 2.79 | 2.81 | 2.78 | 2.86 | 2.75 | 2.77 |
Mid-Grade | 3 00 | 2.77 | 2.89 | 2.93 | 2.93 | 2.96 | 2.86 | 2.91 |
Premium | 3.07 | 3.09 | 3.00 | 3.06 | 3.03 | 3.06 | 3.02 | 3.03 |
26. Gas Prices Using the data from the preceding exercise, find the best predicted price for mid-grade gas for a station that posted $2.78 as the price of regular gas. Is the result close to the actual price of $2.84 for mid-grade gas?
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