Answer: 4 cups of milk
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Work Shown:
2 & 1/2 = 2 + 1/2 = 2+0.5 = 2.5
2.5 cups of milk makes 5 servings
x cups of milk makes 8 servings
Divide the cups of milk over the servings to get this proportion
2.5/5 = x/8
Cross multiply and solve for x
2.5/5 = x/8
2.5*8 = 5*x
20 = 5*x
5*x = 20
x = 20/5
x = 4
You need 4 cups of milk to make 8 servings