So we can simplify this problem so that we may create an equation for it. First we take 750 mL and change it to 0.75 liters so that we may have the same unit of measurement. Then we multiply 0.75 by 9 pitchers. This will be 6.75 liters. We then subtract 6.75 liters from the 8 liter jug, and your answer is 1.25 liters.