Hand It Over!

Hand It Over!

March 24, 2020

When you do one simple thing, like flicking a light switch, your body is actually doing tonsof things. Your eyes and brain have to work together to send your hand to the right spot. And your hand isn’t one thing, but a crazy connection of muscles, bones, and tendons. Our friend Maggie K. wanted to know: just how many muscles are in my hand? Well, there are 17 muscles in the palm of your hand, but that’s not enough – there are also 18 muscles in your forearm that help move your fingers! Sounds like we all have some serious muscle.

Wee ones: Can you find 3 things smaller than your hand?

Little kids: There are 18 muscles in your forearm and 17 in your hand. How many more muscles are in your forearm? Bonus: How many more muscles are in both your forearms than in 1 of your hands?

Big kids: If you add up the muscles in both hands and both forearms, how many muscles is that? Bonus: Not everyone agrees on what counts as a muscle: some people say there are 650 muscles, while others say it’s 840. What’s the difference between those two numbers?


Wee ones: We bet you can! Items could include small toys, berries or other foods, paperclips, seashells or leaves of a houseplant…

Little kids: 1 more muscle in your forearm. Bonus: 19 more muscles.

Big kids: 70 muscles, because there are 17 + 18 = 35 muscles on each side, and 35 + 35 = 70. Bonus: 190 muscles. You can either subtract by regrouping (840 – 650 = 700 – 600 + 140 – 50 = 100 + 90 = 190) or you can add up from 650 (50 brings you to 700, 100 brings you to 800, 40 brings you to 840; 50 + 100 + 40 = 190).<

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About the Author

Laura Overdeck

Laura Overdeck

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.

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