To make dark orange color, ron mixes 3 ounces of red paint with 2 ounces of yellow paint. write the ratio of red paint to yellow paint three ways

The most obvious one is 3:2
This is because you are simply comparing the two amounts, 

From here, all you need to do is multiply both sides by the same number for an equivalent ratio. For example: 

3 X 2 = 6
2 X 2 = 4
6:4

3 X 3 = 9
2 X 3 = 6
9:6

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