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The question after that says to use the least squares regression line tot predict the highway mile of a car that gets 18 mph in the city. Answer to one decimal place. I got 26.8 and it said it was wrong

The question after that says to use the least squares regression line tot predict-example-1

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To draw the least-squares regression line, we first need to calculate the slope and y-intercept of the line based on the given model equation:

predicted highway mpg = 7.95 + 1.046 city mpg

The slope of the line is the coefficient of the city mpg variable, which is 1.046. The y-intercept is the constant term, which is 7.95.

Using these values, we can plot the line on a scatterplot of the data. Here is a table of the data:

Model City MPG Highway MPG

Acura RLX 20 29

BMW 530 24 34

Buick LaCrosse 20 29

Chevrolet Malibu 36 29

Ford Hybrid FWD 43 41

Honda Civic 32 42

Infiniti Q50 Red Sport 20 26

Kia Forte 30 40

Lexus ES 350 22 33

Mercedes Benz AMG S 21 30 30

Mini Cooper Clubman 24 32

Nissan Maxima 20 30

Suburu Legacy AWD 25 34

Toyota Prius ECO 53 58

To plot the line, we can start by choosing two points on the line. We can choose the points where the line intersects the minimum and maximum x-values in the data. The minimum city mpg in the data is 20, so one point on the line is (20, 7.95 + 1.046 * 20) = (20, 29.35). The maximum city mpg in the data is 43, so the other point on the line is (43, 7.95 + 1.046 * 43) = (43, 54.37).

We can now draw a straight line passing through these two points to represent the least-squares regression line.

To use the "up-and-across" method to find the predicted highway mileage of a midsized car that gets 18 mpg in the city, we can start by plotting a point at (18, 0) on the scatterplot. We can then draw a vertical line from this point to the regression line, and then draw a horizontal line from the regression line to the y-axis. The point where the horizontal line intersects the y-axis is the predicted highway mileage for a car that gets 18 mpg in the city.

Using the hand-drawn scatterplot above, we can estimate that the predicted highway mileage for a car that gets 18 mpg in the city is approximately 25.5 mpg.

User Mattb
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