Question

Here are the ingredients in your first recipe:

Banana Cupcakes
makes 10 cupcakes

1 cup granulated sugar

1/2 cup vegetable oil

1 large egg

4 tablespoons sour cream

2 medium-sized ripe bananas, mashed

1 1/2 cups all-purpose flour

1 teaspoon baking soda

1/8 teaspoon salt

1 teaspoon vanilla extract

pinch of nutmeg

You will use the recipe above to answer the following questions:

1. This recipe serves 10, but you need to serve 30. What number will you need to multiply the amount of each ingredient by to adjust the recipe?
2. How did you determine this number?
3. How much vegetable oil do you need for 30 cupcakes?
4. How much flour do you need for 30 cupcakes?
5. What is the difference in the amount of vanilla extract you would need for 30 cupcakes?
6. What is the difference in the amount of salt you would need for 30 cupcakes?

In the real world, even though you make adjustments to a recipe to accommodate the number of people you need to serve, you sometimes round the amount of an ingredient instead of using an exact amount. Which ingredient would it make more sense to round rather than coming up with the exact amount? Why?

Answer 1

1. To adjust the recipe to serve 30 cupcakes instead of 10, you will need to multiply the amount of each ingredient by 3.

2. This number was determined by dividing the desired number of servings (30) by the original number of servings (10). 30/10 = 3.

3. For 30 cupcakes, you will need 3 times the amount of vegetable oil listed in the original recipe. The original recipe calls for 1/2 cup of vegetable oil, so for 30 cupcakes, you will need 3 * (1/2) = **1 and 1/2 cups** of vegetable oil.

4. For 30 cupcakes, you will need 3 times the amount of flour listed in the original recipe. The original recipe calls for 1 and 1/2 cups of all-purpose flour, so for 30 cupcakes, you will need 3 * (1 and 1/2) = **4 and 1/2 cups** of all-purpose flour.

5. The difference in the amount of vanilla extract you would need for 30 cupcakes is calculated by subtracting the amount needed for 10 cupcakes from the amount needed for 30 cupcakes. The original recipe calls for 1 teaspoon of vanilla extract, so for 30 cupcakes, you will need 3 * (1) = **3 teaspoons** of vanilla extract. The difference is therefore 3 - 1 = **2 teaspoons**.

6. The difference in the amount of salt you would need for 30 cupcakes is calculated by subtracting the amount needed for 10 cupcakes from the amount needed for 30 cupcakes. The original recipe calls for 1/8 teaspoon of salt, so for 30 cupcakes, you will need 3 * (1/8) = **3/8 teaspoon** of salt. The difference is therefore (3/8) - (1/8) = **2/8 or 1/4 teaspoon**.

In the real world, it would make more sense to round the amount of an ingredient like salt or nutmeg rather than coming up with the exact amount because these ingredients are used in such small quantities that a slight variation in their amounts is unlikely to have a significant impact on the final product.