Slope as Unit Rate Quick Check

2 of 52 of 5 Items

Question
Use the image to answer the question.

An illustration shows two graphs depicting cost of gasoline per gallon in dollars in store A and B. The first graph shows cost of gasoline per gallon in dollars in store A. The horizontal axis shows gallons ranging from 0 to 20 in increments of 5. The vertical axis shows the cost in dollars ranging from 0 to 70 in increments of 10. Four data points are plotted on the graph at left parenthesis 0 comma 0 right parenthesis, left parenthesis 5 comma 20 right parenthesis, left parenthesis 10 comma 40 right parenthesis, and left parenthesis 15 comma 60 right parenthesis. A line connects all the data points. The second graph shows cost of gasoline per gallon in dollars in store B. The horizontal axis shows gallons ranging from 0 to 10 in increments of 2. The vertical axis shows the cost in dollars ranging from 0 to 30 in increments of 2. Three data points are plotted on the graph at left parenthesis 0 comma 0 right parenthesis, left parenthesis 4 comma 14 right parenthesis, and left parenthesis 8 comma 28 right parenthesis. A line connects all the data points.

The proportional relationship between the cost of gasoline and the number of gallons of gasoline from Store A and Store B are displayed in the graphs. Use the graphs to interpret the store that has the cheaper cost of gasoline per gallon.

(1 point)
Responses

To determine which store has the cheaper cost of gasoline per gallon, we need to look at the slope of the line in each graph. The slope represents the unit rate, which is the cost per gallon of gasoline.

In Store A, the slope of the line connecting the data points is $20 per 5 gallons, or $4 per gallon.

In Store B, the slope of the line connecting the data points is $14 per 4 gallons, or $3.50 per gallon.

Therefore, Store B has the cheaper cost of gasoline per gallon at $3.50 compared to Store A's $4.