Answer:
-Below.
Step-by-step explanation:
4) When the carton is unopened the number of servings x = 0.
So there are 64-4(0) = 64 ounces in an unopened carton.
5) When all the milk has been poured out no. ounces left (y) = 0 so
64 - 4x = 0
4x = 64
x = 16
So each serving contains 16 ounces of milk.