Answer:the missing values are 7, 28 and 31.5
Step-by-step explanation:
What makes the relationship between two variables to be proportional is the constant of proportionality. With the constant of proportionality determined, if there is a change in the value of one variable, the corresponding change in value of the other variable is easily determined.
The variables given are servings and ounces.
Let the missing values be represented by a,b and c.
Therefore,
21/12 = a/4
a = 1.75 × 4
a = 7
21/12 = b/16
b = 1.75 × 16
b = 28
21/12 = c/18
c = 1.75 × 18
c = 31.5
