Question

Question
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?

Answer 1

Rate of change = (30 − 15) / (8 − 4) = 15/4 = 3.75.

So the cost increases by $3.75 per gallon.