<span>There are a few combinations of mixed numbers that can have a sum of 3. A mixed number must have one whole number and one fraction. Combinations of mixed numbers that can have a sum of 3 are 1 and 1/2 + 1 and 1/2, 1 and 1/3 + 1 and 2/3, 1 and 5/8 + 1 and 3/8 and so on.</span>
if you take 80 and 120 on the graph look at the middle you get 100 and in between 2 and 3 you get 2.5 so it would take 2.5 gallons of gas for 100 miles
