Question

a freight train is carrying goods across the country. the number of gallons of fuel it has used varies directly with the distance it has traveled. see the graph below.
(a) how many miles does the train travel per gallon?
(square) mile(s)
(b) what is the slope of the graph?
(square)

Explanation:

Step1: Pick point from graph

Choose point $(100, 200)$: 100 miles, 200 gallons.

Step2: Calculate miles per gallon

Divide miles by gallons.
$\frac{100}{200} = 0.5$

Step3: Identify slope formula

Slope $m = \frac{\text{gallons}}{\text{miles}}$

Step4: Compute slope using point

Use $(100, 200)$ to find slope.
$m = \frac{200}{100} = 2$

Answer:

(a) 0.5 mile(s)
(b) 2