Question

A recipe calls for 3/4 cup of butter. Angie wants to triple the recipe, but she has only 1 5/8.

How much butter must she borrow from a neighbor?

Answer 1

Let's start out by tripling the original recipe to see how much butter Angie needs.


`(3)/(4) * 3 = total`

`(3* 3)/(4) = total`

`(9)/(4) = total`

`2 (1)/(4) = total`

So we need
`2 (1)/(4)` cups of butter, but Angie only has
`1 (5)/(8)`. Let's subtract what Angie has from the total to see how much more she needs.


`2 (1)/(4) - 1(5)/(8) = n`

`(9)/(4) - (13)/(8) = n`
we will need the least common denominator for both fractions

`(2)/(2) *((9)/(4)) - (13)/(8) = n`

`(18)/(8) - (13)/(8) = n`

`(5)/(8) = n`

So Angie need
`(5)/(8)` cups more of butter for the recipe.