A hybrid car averages 607 miles on a 12.1 gallon tank of gas. Manny is planning a 1220 mile vacation in his car. How many gallons of gas will his car burn?
We can solve with a proportion
12.1 / 607 = x / 1220 cross-multiply
1220 * 12.1 = 607 * x simplify
14762 = 607 * x divide both sides by 607
About 24.32 gallons = x