If you’ve ever gone berry-picking, you know how berry bushes go bonkers. As with other fruits, the plant first grows lots of flowers, then each flower turns into a fruit, like an apple, a peach – or a berry. All these fruits have seeds inside. If those seeds land on the ground, they grow into new plants, which grow even more fruit. The strawberry might be the coolest fruit of all: it’s the only one that has its seeds on the outside, and it has lots of them. So our friend Elley C. asked a crazy question: are there more strawberries or people in the world? Well, every year we grow about 4 1/2 million tons of berries. A ton has 2,000 pounds, so that comes to about 9 billion pounds of strawberries. Whoa! The world has “only” about 7 1/2 billion people, so that’s more than a whole box of berries per person! Looks like the berries win this one.
Wee ones: If you eat an apple, an orange, a strawberry, and a peach, how many fruits do you eat?
Little kids: If you have a box of 9 strawberries and you eat 1, how many are left for other people to eat? Bonus: If 2 friends share that number, how many berries does each friend get?
Big kids: If you have 22 strawberries, and need 7 strawberries to make a really good smoothie, how many smoothies can you make? Will you have any berries left? Bonus: If you can get more berries in boxes of 10, how many more boxes do you need to make 6 smoothies total?
The sky’s the limit: If you have 3 boxes of strawberries, and the 1st and 2nd boxes together have 17 berries, the 2nd and 3rd have 22 berries, and the 1st and 3rd together have 19 berries, how many berries are there in each box?
Wee ones: 4 fruits.
Little kids: 8 berries. Bonus: 4 berries per friend.
Big kids: 3 smoothies, with 1 berry left over. Bonus: You need 42 berries to make 6 smoothies, so you need 2 more boxes of 10.
The sky’s the limit: 7, 10, and 12 berries. If the 1st and 3rd have 19 berries, and the 2nd and 3rdhave 22, that means swapping in the 2nd box for the 1st box jumped it by 3 berries. The 2nd box has 3 more berries than the 1st. We know the 1st and 2nd together have 17, which is like having the 1st box, plus another 1st box, plus 3 extra berries. If that adds up to 17, then 2 of that 1st box would give you just 14, and you have 7 per box. That means the 2nd box has 3 more than that, which is 10. And since the 2nd and 3rd add up to 22, the 3rd box must have 12.
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.