Answer:
The quantities used by Manuela were correct
Step-by-step explanation:
The question is
Did Manuela use the right quantities?
Let
x -----> the parts of oil
y ----> the parts of vinegar
we know that
The ratio of the parts of oil by the parts of vinegar of recipe is
Determine the relation used by Manuela
Compare with the recipe
Is true, the quantities are proportional
therefore
The quantities used by Manuela were correct