4. Maddie is making pineapple punch for her birthday party. The recipe says you need 3 cups of pineapple juice for every 4 cups of ginger ale. If she uses 16 cups of ginger ale, how much pineapple juice will she
need?

The ratio of pineapple juice to ginger ale is 3:4. To get from 4 cups of ginger ale to 16 cups, we multiply by four. To keep the ratio, we do the same to the amount of pineapple juice so there should be 12 cups of pineapple juice. To check our ratio, we can see that 12:16 simplifies to 3:4 when we divide by four.

12 cups of pineapple juice

21/2 or 5/2