A car travels 150 miles using 5 gallons of fuel. How many gallons are needed to travel 450 miles?

Step 1: Identify the given values. The car travels 150 miles using 5 gallons of fuel. We need to find out how many gallons are needed to travel 450 miles.

Step 2: Find out the car's fuel efficiency. This is done by dividing the distance travelled by the amount of fuel used. In this case, 150 miles / 5 gallons = 30 miles per gallon.

Step 3: Use the fuel efficiency to find out how many gallons are needed to travel 450 miles. This is done by dividing the distance needed to travel by the car's fuel efficiency. In this case, 450 miles / 30 miles per gallon = 15 gallons.

So, the car would need 15 gallons of fuel to travel 450 miles.