A recipe for orange water says, "Mix 3 teaspoons yellow water with 1 teaspoon red water." For this recipe, we might say: "The ratio of teaspoons of yellow water to teaspoons of red water is 3:1." Write a ratio for 2 batches of this recipe.
Write a ratio for 4 batches of this recipe.
Explain why we can say that any two of these three ratios are equivalent.