Does anyone *really* like fruitcake? After all, it’s a pile of dried fruit mashed into the shape of a cake. It takes months to go bad, since even germs don’t want to eat it. Grown-ups who get a fruitcake as a present sometimes re-gift it to someone else to get rid of it. And now, they can throw it. Today is National Fruitcake Toss Day, and every year a town in Colorado holds a big contest to find out which kid can toss fruitcake the farthest. They throw it using a catapult — a big machine with a long arm for flinging things — and as you’ll see from the math, fruitcake can fly far and fast.
Wee ones: If your fruitcake has raisins, craisins, and apricot in it, how many types of fruit does it mash together?
Little kids: If you toss your 6th fruitcake, then your 7th, then your 8th, what number fruitcake do you toss next? Bonus: If each fruitcake uses 4 cups of dried fruit, how many cups do you need to make your next 2 fruitcakes?
Big kids: If your catapult has a 5-foot-long arm and can hurl a fruitcake 5 times as far as that, how far will it fly? Bonus: If you want the fruitcake to fly 80 feet, how long would the arm have to be if it always throws 5 times its length?
Wee ones: 3 types of fruit.
Little kids: Your 9th fruitcake. Bonus: 8 cups.
Big kids: 25 feet. Bonus: 16 feet long.
Laura Bilodeau Overdeck is founder and president of Bedtime Math Foundation. Her goal is to make math as playful for kids as it was for her when she was a child. Her mom had Laura baking before she could walk, and her dad had her using power tools at a very unsafe age, measuring lengths, widths and angles in the process. Armed with this early love of numbers, Laura went on to get a BA in astrophysics from Princeton University, and an MBA from the Wharton School of Business; she continues to star-gaze today. Laura’s other interests include her three lively children, chocolate, extreme vehicles, and Lego Mindstorms.