Lionfish look cool with their stripes and spikes, but they’re poisonous and taking over the Atlantic Ocean. They have no “predators,” or animals that like to eat them, and one lionfish can lay 30,000 eggs at a time! Luckily, lionfish are very tasty to us people, and we can eat them without being poisoned. The question is, can we eat up all these fish before they eat everyone else?
Wee ones: How many white-tipped spiky fins does this fish have along the top? Count them up!
Little kids: If every other fish you catch is a lionfish, starting with the 2nd fish, is your 9th fish a lionfish? Bonus: How many lionfish have you caught by then?
Big kids: All lionfish appear to be the great-great-great…grandchildren of just 1 of a set of 6 fish. If those 6 fish each laid 30,000 eggs, how many new baby fish did they have in total? Bonus: If 25 restaurants each serve 2 lionfish each night, how many fish can they all serve in a week?
Answers:
Wee ones: 9 fins.
Little kids: No, it’s some other kind of fish. Bonus: 4 lionfish (the 2nd, 4th, 6th and 8th).
Big kids: 180,000 fish. Bonus: 350, since together they serve 50 per night.
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.