A graph of the cost of gas purchased depending on the number of gallons pumped has the points (4, 15) and (8, 30). What is the rate of change in the cost of the gas as each gallon is pumped?

1 answer

To find the rate of change in the cost of gas as each gallon is pumped, we first need to determine the slope of the line that passes through the two points given.

Using the formula for slope, which is (y2 - y1) / (x2 - x1), we can plug in the values from the points (4, 15) and (8, 30):

(30 - 15) / (8 - 4) = 15 / 4 = 3.75

Therefore, the rate of change in the cost of gas as each gallon is pumped is $3.75.