Tom and Martha are making punch for a party. The proportions given in the recipe are 2 parts of lemonade to 1 part each of pineapple juice and ginger ale. If they need 6 liters of punch, how many liters of each of the ingredients should they buy?

They need to buy 3 litters of lemonade, 1.5 litters of pineaple juice and 1.5 litters of ginger ale.

Step-by-step explanation:

In order to calculate the amount of each ingredient they need for 6 liters of punch we can first create fractions for each ingredient based on the proportions we were given. This is shown bellow:

2 litters lemonade + 1 litter pineapple juice + 1 litter ginger ale = 4 litters punch

Then we have:

lemonade = 2/4

pineaple juice = 1/4

ginger ale = 1/4

If we want to make 6 liters of punch we can just apply this fractions to know how much of each we need:

lemonade = 6 * (2/4) = 12/4 = 3 litters

pineaple juice = 6 * (1/4) = 1.5 litters

ginger ale = 6 * (1/4) = 1.5 litters

They need to buy 3 litters of lemonade, 1.5 litters of pineaple juice and 1.5 litters of ginger ale.