Answer:
216 miles
Step-by-step explanation:
Let's set up a proportion using the following setup.
miles/gallons=miles/gallons
We know the car can travel 156 miles on 13 gallons. We don't know how many miles the car can travel on 18 gallons, so we can say the car can travel x miles on 18 gallons.
156 miles/13 gallons=x miles/18 gallons
156/13=x/18
We want to find out what x is. Therefore, we have to get x by itself. x is being divided by 18. The inverse of division is multiplication, so we can multiply both sides by 18.
18*156/13=x/18*18
18*156/13=x
18*12=x
216=x
x=216 miles
The car can travel 216 miles on 18 gallons of gas.