Given:
Elise is making punch for the party that requires 2 parts of fruit juice for every 5 parts of ginger ale.
To make the punch, she uses 18 ounces of fruit juice and 3 containers of ginger ale.
To find:
The number of ounces in each container of ginger ale.
Solution:
Let n be the number of ounces in each container of ginger ale.
According to the question, the ratio of fruit juice and ginger ale is 2:5. it means,




Divide both sides by 2.

So, ginger required for punch is 45 ounces.
Number of containers = 3
Number of ounces in each container of ginger ale = n
Number of ounces in 3 containers of ginger ale = 3n
Now,

Divide both sides by 3.

Therefore, 15 ounces are in each container of ginger ale.