Question

How many cups of each to triple a recipe of 1/2 cup of water, 1/3 cup of sugar, 1/8 cup of baking soda and 1 1/2 cup of butter?

Answer 1

`"water : sugar : baking soda : butter"`
`1 1/2color(white)(..):color(white)(..)1color(white)(..):color(white)(d..)3/8color(white)(.dddd.):color(white)(..) 4 1/2`

Explanation:

The most straight way to deal with this is use the horizontal format for ratio.

For 1 portion we have:

`"water : sugar : baking soda : butter"`

`color(white)("d")1/2color(white)("dd"):color(white)("d")1/3color(white)("dd"):color(white)("dddd")1/8color(white)("dddd"): color(white)("d")3/2`

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The above is for 1 portion of recipe but we need 3 portions. So multiply everything by 3. I choose to write it like this:

`3xx (1/2:1/3:1/8: 3/2 )`

This is the same as:

`1/2:1/3:1/8: 3/2`

`1/2:1/3:1/8: 3/2`

`ul(1/2:1/3:1/8: 3/2larr" Add")`
`3/2:3/3:3/8:9/2`

So for 3 lots we have:

`"water : sugar : baking soda : butter"`
`1 1/2color(white)(..):color(white)(..)1color(white)(..):color(white)(d..)3/8color(white)(.dddd.):color(white)(..) 4 1/2`