Question

A recipe calls for `1/4` cup of sugar when being made for 4 people. How much sugar is needed if the recipe is adjusted to feed 7 people?

Answer 1

`7/16` cup

Explanation:

We can use a ratio to find the answer. We can relate the original recipe in the numerators (4 people and `1/4` cup of sugar) and the adjusted amounts in the denominators (7 people and the amount of sugar needed):

`("4 people"/"7 people")=("1/4 cup"/"x cup")`

To make things easy, I'll drop the units:

`4/7=(1/4)/x`

We can now cross multiply to find `x`:

`4x=7/4`

`x=7/16`