Family Reunion!
It's that time of year again! Your whole family is gathered in one spot to enjoy each others' company, play games, and of course eat good food. This year you're helping out with the food. Your mentor, Uncle Arthur, needs your help making brownies for everyone. The idea of making enough for 200 people simply blows your mind, but Uncle Art has a plan. He's an experienced cook and he knows how to use a scale factor! The recipe calls for 4 cups of flour, 2 cups of sugar, 2 eggs, 1.25 cups of cocoa, 1.5 cups of water, and 1 cup of vegetable oil. This yields about 10 brownies. He sets up a proportion to figure out how many cups he would need for 200 people that looks like this:
He crossed multiplied and solved for 'x' and got 80 cups of flour needed. Wow. That's a lot of cups! It would be hard to keep count of all that flour, so he decides to figure out how many cups he needs to make 25 brownies.
It turned out he would need only 10 cups for this! That's way better than 80. You did the math, and figured if you made 25 brownies each time, and needed 200 brownies total, it would take 8 batches to complete! Thanks to Uncle Art's scale factor, you now know how much flour you need and can easily find the amounts for the other ingredients.