Do we even want to run in the rain? Usually no. But if you’re stuck in the rain, will you get wetter running or walking? On the one hand, some number of drops will land on your head each minute. But as you run forward, the front of you gets wet, because there are always raindrops hanging in the air on their way down. Running may be better: Assuming no wind, the front of you will catch the same number of drops whether you run or walk. But the slower you go, the longer your head is catching drops. Maybe the real answer is to just open an umbrella.
Wee ones: Who’s wetter, you with 10 raindrops on your head, or your pet poodle with 8 raindrops on his?
Little kids: If you run 2 steps in the rain, then walk 3 steps, then run 4 steps…what do you guess you do next? Bonus: How many wet steps did you take in total?
Big kids: If each foot-deep chunk of air in front of you has 50 falling raindrops, how many drops do you soak up if you walk 10 feet? Bonus: Which way will you get wetter, catching 25 drops per second while you run for 4 seconds, or catching 15 per second walking for 8 seconds?
Answers:
Wee ones: You’re wetter with 10 raindrops.
Little kids: Walk 5 steps to continue the pattern. Bonus: 14 steps.
Big kids: 500 drops. Bonus: You’ll get wetter walking, with 120 raindrops instead of 100.
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.