Reasoning proportionally to answer real-world problems: Applied

Leon seems very busy in the kitchen. Ah! He’s baking cakes for his school’s cake sale! You look a little puzzled, Leon. Your recipe calls for three eggs… but you need to make five cakes… and you’re wondering how many eggs that is?

We can help you figure that out! From the recipe, we know that the ratio of eggs to cake is three eggs to one cake. Three to one. If you want all the cakes to turn out just as the first one, you need to maintain the same ratio of eggs to cake. You need to increase the ingredients proportionally.

So let’s see. How did we get from one cake to five? We did one cake five times. That’s one multiplied by five. Now we need to do the same for the eggs.

Three eggs five times. Three multiplied by five is… 15. There we have it! You will need 15 eggs to make your five cakes, Leon. Happy baking!