When you mix two colors of paint in equivalent ratios, the resulting color is always the same. How many cups of yellow paint should you mix with 3 cups of blue paint to make the same shade green? Explain.
You should mix 15 cups of yellow paint, because it takes 5 cups of yellow paint + one cup of blue paint to make the same green. Since there's 3 cups of blue paint, multiply that by 5, and you get 15.
