Answer:
$63.54
Step-by-step explanation:
You first need to find how much it costs for one gallon of gas. To do this, you divide the amount of money by the amount of gallons;
$21.15 / 6 gallons = $3.53
For one gallon of gas, it costs $3.53. To find how much 18 gallons would cost, we multiply how much gas/gal costs by 18 gallons.
$3.53 x 18 gallons = $68.54 for 18 gallons of gas
I hope this helps!
