SOLUTION: We expect a car's highway gas mileage to be related to its city gas mileage (in miles per gallon, mpg). Data for all 1137 vehicles in the government's 2013 Fuel Economy Guide give

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Question 1051545: We expect a car's highway gas mileage to be related to its city gas mileage (in miles per gallon, mpg). Data for all 1137 vehicles in the government's 2013 Fuel Economy Guide give the regression line
highway mpg = 6.785 + (1.033 × city mpg)
for predicting highway mileage from city mileage.
a) What is the slope of this line? (Enter your answer to three decimal places.
b)What is the intercept? (Enter your answer to three decimal places.)
c)Find the predicted highway mileage for a car that gets 11 miles per gallon in the city. (Round your answer to two decimal places.)
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
your equation is:

highway mpg = 6.785 + 1.033 * city mpg

the slope would be 1.033.
the y-intercept would be 6.785

if you let y = highway mpg and you let x = city mpg, the equation becomes:

y = 6.785 + 1.033 * x

if you re-order the terms in descending order of degree, you get:

y = 1.033 * x + 6.785

this is the slope intercept form of the equation for a straight line.

that form is y = mx + b

m is the slope and b is the y-intercept.

when the car gets 11 miles per gallon in the city, x is equal to 11.

formula becomes y = 1.033 * 11 + 6.785

solve for y to get y = 18.148 miles per gallon.

you can graph the equation and find the intersect between the equation and the vertical line of x = 11.

the intersection should be at y = 18.148.

the coordinate point should show at (11,18.148).

here's the graph.

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