Final answer:
To find a linear model that gives the fuel efficiency of a car as a function of its weight, we can use the given data to find the equation of the line. The linear model is E = -8w + 45. The fuel efficiency of a car that weighs 3 tons is 21 mpg.
Step-by-step explanation:
To find a linear model that gives the fuel efficiency E (in mpg) of a car as a function of its weight w (in tons), we can use the given data to find the equation of the line. We have two data points: (2, 29) and (2.5, 25).
Using the slope formula, we can find the slope of the line:
slope = (25 - 29) / (2.5 - 2) = -4 / 0.5 = -8
Now, let's use the point-slope formula to find the equation of the line:
E - 29 = -8(w - 2)
Simplifying the equation, we get:
E = -8w + 45
Thus, the linear model that relates fuel efficiency (E) to car weight (w) is E = -8w + 45.
To find the fuel efficiency of a car that weighs 3 tons, substitute w = 3 into the equation:
E = -8(3) + 45 = 21