Complete Question
A peanut butter cookie recipe calls for 3 1/2 cups of flour to make 6 dozen cookies. How many cups of flour must be used to make 20 dozen?
Answer:
11 2/3 cups of flour
Explanation:
From the above question:
6 dozen = 3 1/2 cups of flour
20 dozen = x
Cross Multiply
6 dozen × x = 20 dozen × 3 1/2 cups of flour
x = 20 dozen × 3 1/2 cups of flour/6 dozen
x = 20 × 7/2 /6
x = 140/2 ÷ 6
x = 140/2 × 1/6
x = 140/12 cups of flour
x = 11 8/12
= 11 2/3 cups of flour
Therefore, 11 2/3 cups of flour must be used to make 20 dozen.