6th and 7th grade staar testing...Proportions

Question

6th and 7th grade state testing focuses on the students ability to solve questions using proportions in many different formats. For example: precent proportions, conversions, probability, and comparing to ratios.

A recipe calls for 3 cups of flour to make 12 cookies.

How many cups of flour are needed to make 20 cookies?

Answer 1

I use a chart to help organize the students thinking...it's called the Word, Known, Unknown chart

Word ratio = Known Ratio = Unknown

flour = 3 = x

cookies 12 20

Keeping things organized you can clearly see the "sames" are together.

Cross multiply....3*20=60

equation: 60=12x

Divide by 12

the answer is: 5 cups of flour