Kevin is mixing paint to make orange. The ratio of red paint to yellow paint is 3 oz to 5 oz. How much yellow paint should he mix with 9 oz of red paint?
So if the ratio of red:yellow is 3:5 you have to move in multiples of that ratio. 9/3=3 so the ratio multiplies by 3 ending with 9:15 so 15 Oz of yellow. (3:5) x 7 = 21:35. (3:5)x14=42:70