Answer :
Using proportions, it is found that if the recipe is doubled he will need 60 ounces of milk.
What is a proportion?
A proportion is a fraction of a total amount, and the measures are related using a rule of three.
The recipe calls for 3 cups and 6 ounces = 30 ounces, as each cup has 8 ounces. Hence, if the recipe is doubled, the number of ounces will need is given by:
n = 30 x 2 = 60.
More can be learned about proportions at https://brainly.com/question/24372153
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