August 13, 2019

Idaho is called The Gem State, but you can find another great thing in the ground there: potatoes! Idaho grows more potatoes than any other state. Last year, that added up to 13.5 billion pounds of potatoes – 41 pounds for every person in America. There are all kinds of ways to eat potatoes, but our favorite shape is the “rectangular prism,” better known as the French fry. So how many fries can you make from 1 potato? Well, it depends on the potato’s weight, but a 3-ounce serving will have 12 to 15 fries. So how many fries can we make from those 41 pounds of potatoes – and how long do you think it would take you to eat them? Read on to find out!

*Wee ones: *If you eat 3 fries and your friend eats 7, who eats more?

*Little kids: *If you eat 3 regular rectangular prism fries and 7 curly fries, how many fries do you eat in total? *Bonus: *What numbers do you say for the next 5 fries you eat?

*Big kids: *Americans eat 115 pounds of potatoes per person each year, on average! How many more pounds is that than the 41 pounds Idaho grows for each American? *Bonus: *If a 3-ounce potato makes 15 fries, how many fries can you make with a 1/2-pound potato? (Reminder: 1 pound has 16 ounces.)

*The sky’s the limit: *To find the volume of a rectangular prism, you multiply length x height x width. If you have a pile of steak fries that are all 3 inches long by 1/2-inch high by 1/2-inch tall, how many fries together take up 12 cubic inches?

Answers:

*Wee ones: *Your friend, because 7 is more than 3.

*Little kids: *10 fries, because 3 + 7 = 10.* Bonus: *11, 12, 13, 14, 15.

*Big kids: *74 more pounds. *Bonus: *40 fries. You can make 5 fries with 1 ounce; a 1/2-pound potato is equal to 8 ounces, and each of the 8 ounces makes 5 fries, so 8 x 5 = 40.

*The sky’s the limit: *16 fries. One shortcut to get this: if you want one long 12-inch by 1-inch by 1-inch stick, it needs to be 4 fries long (since each is 3 inches), and then 2 fries tall and 2 fries wide. 4 x 2 x 2 = 16. Or another way: each fry has a volume of 3/4 cubic inch, because 3 x 1/2 x 1/2 = 3/4. Dividing 12 by 3/4 is the same as multiplying it by 4/3; 12 x 4/3 = 48/3 = 16.

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.

- Nature’s Water Shooter May 30, 2020
- Face-Off with a Mountain May 29, 2020
- A Quick Drink for a Big Dog May 28, 2020
- The Bounciest Mile May 27, 2020
- A Million-Dollar Speedbump May 26, 2020