Question

A recipe called for the ratio of sugar to flour to be 10 : 3. If you used 70 ounce of sugar, how many ounces of flour would you need to use?

Answer 1

21 ounces

Explanation:

We will set up a proportion for this problem. First we use the ratio we are given of sugar to flour:

10/3

The second ratio will be int he same format, sugar to flour. We know we are using 70 ounces of sugar, and an unknown amount of flour (we will use x):

70/x

This gives us the proportion

10/3 = 70/x

Cross-multiply:

10(x) = 3(70)

10x = 210

Divide both sides by 10:

10x/10 = 210/10

x = 21