Final answer:
Sofia can drive 459 miles using 18 gallons of gas.
Step-by-step explanation:
To find out how many miles Sofia can drive using 18 gallons of gas, we first need to determine the rate at which she consumes gas. We can do this by dividing the number of miles driven by the number of gallons used:
Rate = Distance / Gas used
Rate = 204 miles / 8 gallons = 25.5 miles/gallon
Using this rate, we can calculate the number of miles Sofia can drive with 18 gallons of gas:
Miles = Rate * Gas
Miles = 25.5 miles/gallon * 18 gallons = 459 miles
Therefore, Sofia can drive 459 miles using 18 gallons of gas.