Consider the recipe for making tomato and garlic pasta.
2 cups noodles + 12 tomatoes + 3 cloves garlic → 4 servings pasta
If you have 7 cups of noodles, 27 tomatoes, and 9 cloves of garlic, how many servings of pasta can you make? Which ingredient limits the amount of pasta that it is possible to make?
Let's figure out how many recipes worth we have of each of the ingredients:
7 cups noodles * 1 recipe/2 cups = noodles for 3.5 recipes
27 tomatoes * 1 recipe/12 tomatoes = tomatoes for 2.25...