Cake for the World

Here's your nightly math! Just 5 quick minutes of number fun for kids and parents at home. Read a cool fun fact, followed by math riddles at different levels so everyone can jump in. Your kids will love you for it.

Cake for the World

March 28, 2016

First, thank you everybody for sending really fun and fabulous questions for us to answer for you! As a reminder, any of you can ask one yourself, either for our website or for the next Bedtime Math book. Just email your question to, and let us know if you’d like us to answer you here or in the book!

Today we have a great one from Grady S., who wants to know how much cake the whole world eats every day. Well, that depends on how often we eat cake — hey, we’d love that to be every meal if we could. At least for the US, back in 1999 we ate about 6 million cakes each day, and that was for 280 million people; we now have 320 million. So maybe we’re at 7 million cakes a day. The whole world has about 20 times as many people (7 billion), but other countries may not each as much cake as the US. Still, the world probably eats between 50 and 100 million cakes a day! For the ones that are birthday cakes, that’s a lot of decorating.

Wee ones: If you eat your 3rd bite of cake, then your 4th bite, then your 5th…what bite comes next?

Little kids: If you cut 1 cake into 12 slices, and another same-sized cake into 9 slices, which one has bigger slices?  Bonus: How many more slices does the 12-slice cake have?

Big kids: If you have 8 friends and 4 cousins, and you eat 2 slices of cake at each person’s birthday party, how many 12-slice birthday cakes do you eat each year yourself?  Bonus: If that’s true for the roughly 320 million people in the US, how many cakes do we eat in one year?




Wee ones: Your 6th bite.

Little kids: The cake with 9 slices — the cake gets spread among fewer slices.  Bonus: 3 slices more.

Big kids: 2 cakes, since you eat 24 slices.  Bonus: 640 million cakes per year. That’s a lot less than 7 million per day, so we’re eating a lot of cake beyond people’s birthdays!

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About the Author

Laura Overdeck

Laura Overdeck

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.

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