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Susan used 1 2 tablespoons of red food coloring to make 3 4 cups of cake icing. If Susan's recipe is for 1 cup of icing, how much red food coloring will she need to make 1 2 the recipe? A) 1 6 tablespoons of food coloring B) 1 4 tablespoons of food coloring C) 1 3 tablespoons of food coloring D) 1 9 tablespoons of food coloring

2 Answers

4 votes

Answer:

it's 1/3!!!

Explanation:

User Mark Bostleman
by
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3 votes

Answer:

B) 1/4 tablespoons

Explanation:

It looks like we don't need to worry about the 3/4.

So 1 full cup takes 1/2 a tablespoon of food coloring. Hopefully it is simple to figure out how much you need if you double the recipe. So if you wanted 2 cups it would be like making the one recipe twice. So 1 cup twice means 1/2 a tablespoon twice. Or 1/2+1/2 = 1 tablespoon.

It works similarly when you are making less. if you want half you cut everything in half. So you are cutting the 1 cup in half to 1/2 a cup, you are also cutting the 1/2 a tablespoon in half. or in other words (1/2)/2 or one half divided by 2. If you are rusty with fraction division it may be easier to think what do you need two of to make 1/2? The answer is 1/4. So 1/4 + 1/4 = 2/4 = 1/2

As a quick how to on fraction division you always want to have a fraction divided by a fraction. You also need to know you can write a whole number as that number over 1, or 2 = 2/1. Now, when you have a fraction divided by a fraction you take the fraction in the denominator, flip it and now multiply the top fraction by it. I will demonstrate with this one in this problem.

(1/2)/2 Make 2 2/1

(1/2)/(2/1) now flip and multiply

1/2 * 1/2

1/4

User Ramiro
by
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