The next state on our trip is the Sunflower State, better known as Kansas. There’s some cool math happening here: the geographic center of the lower 48 states is in Kansas! Over 100 years ago, surveyors balanced a cardboard cutout of the U.S. on a pin, and found the center was near a town called Lebanon, Kansas. It’s also the middle of “America’s Bread Basket,” since Kansas grows more wheat than any other state. You know what a half-gallon of milk looks like? A “bushel” is more than 18 of those put together, and the 20,000 wheat farms in Kansas grow 333 million bushels of wheat every year. That’s 1/5 of all the wheat in the country, and could make 36 BILLION loaves of bread. Let’s see how fast all of America can eat that!
Wee ones: If you make a sandwich with peanut butter, jelly, and 2 slices of bread, how many layers are in the sandwich?
Little kids: Pretend you’re like that piece of cardboard balancing on a pin. Stand on 1 leg, and count until you tip over. See how high a number you can reach! Bonus: If you take 3 hours to drive from Topeka (Kansas’ capital) to Lebanon, spend 2 hours balancing on 1 leg at the center of the US, and drive back in the same time it took to drive there, how long does your trip take?
Big kids: If Kansas makes 1/5 of all the wheat in the country, and no state makes more than it, can another state make 1/4 of all the wheat in the country? Bonus: If the wheat from Kansas can make 36 billion loaves of standard sandwich bread, how many loaves could it make if a baker made the loaves 3 times the size of standard sandwich bread?
The sky’s the limit: If a standard loaf of bread has 2 dozen slices, how many 2-slice sandwiches can you make with your 110 loaves from Kansas?
Answers:
Wee ones: 4 layers.
Little kids: Different for everyone…see how long you can stand on 1 leg! Bonus: 8 hours, because 3 + 2 + 3 = 8.
Big kids: No, because 1/4 is bigger than 1/5. Bonus: 12 billion loaves, because baking loaves 3 times as big will make 1/3 of the 36 billion loaves, and 36 / 3 = 12.
The sky’s the limit: You can make 1,320 sandwiches. Each loaf makes 1 dozen, or 12, sandwiches. Using partial products: 12 x 110 = 12 x 100 + 12 x 10 = 1200 + 120 = 1,320.
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.