A bread recipe uses 2 1/2 cups flour per loaf. If you bake 6 loaves, how many cups of flour are needed?

• A. 7 1/2 cups
• B. 12 cups
• C. 10 cups
• D. 15 cups

Answer: (D)

When you scale a recipe, you multiply the amount for one unit by the number of units you’re making. Here, each loaf needs 2 1/2 cups of flour, and you’re baking six loaves, so you multiply 2 1/2 by 6.

2 1/2 is the same as 5/2. Multiply: (5/2) × 6 = 30/2 = 15. So you need 15 cups of flour.

Think of it as adding 2 1/2 cups six times: 2.5 + 2.5 + 2.5 + 2.5 + 2.5 + 2.5 = 15 cups.

For reference, fewer loaves would yield smaller totals: three loaves would need 7 1/2 cups, four loaves would need 10 cups, and six loaves require 15 cups.