If a car 80 miles on 5 gallons of gaseline, how many gallons will be needed for 200 miles

Question

 If a car 80 miles on 5 gallons of gasoline, how many gallons will be needed for 200 miles?

Answer 1

This is a simple ratio problem: a car has a specific average mpg (miles per gallon) and according to this idealistic problem we can see that this car has the ability to go 80 miles on 5 gallons of gas. So, in order to see how many gallons are needed to make a 200 mile trip we can set up a ratio. 

 

80 miles / 5 gallons = 200 miles / N gallons 

Where N stands for the number of gallons

 

Now, we can just cross multiply to solve this algebraically:

 

80 miles x N gallons = 200 miles x 5 gallons     OR

80N = 1000 

N = 1000/80 = 12.5 gallons