# Debbie needs to fill juice cups for her little brothers birthday party. There are 20 juice cups and each juice cup holds 10 fluid ounces. The juice comes in 1-gallon bottles. How many 1-gallon bottles of juice will Debbie need to purchase?

If she has 20 juice cups that each fill 10 ounces, then you can do the equation $20 \cdot 10$ to find out that you need $200$ ounces of juice. Now, you must find out how many ounces are in a gallon, so we are going to break it down.
There are 8oz in a cup. 2 cups in a pint, so 16oz in a pint. 2 pints in a quart, so 32oz in a quart. 4 quarts in a gallon. So, $4 \cdot 32 = 128$. But, since she can only buy 1-gallon jugs, she would have to buy 2.