Question

if 7 cups of flour are needed to make a cake for 9 people, how many cups are needed to make a cake for 15 people?

Answer 1

7 cups of flour ... 9 people
x cups of flour = ? ... 15 people

If you would like to know how many cups are needed to make a cake for 15 people, you can calculate this using the following steps:

7 * 15 = 9 * x     /9
x = 7 * 15 / 9
x = 35/3
x = 11 2/3 cups of flour

Result: 11 2/3 cups of flour are needed to make a cake for 15 people.