Clock-a-Doodle-Doo

Here's your nightly math! Just 5 quick minutes of number fun for kids and parents at home. Read a cool fun fact, followed by math riddles at different levels so everyone can jump in. Your kids will love you for it.

Clock-a-Doodle-Doo

August 2, 2014

Most of us don’t live on farms, but we all know that the sound of a rooster crowing as the wake-up call when the sun rises. Roosters seem to like their role as alarm clock — and they work like clocks more than we realized. Last year scientists figured out that even if you put roosters in a dim room all day and all night, the birds crowed at the right time anyway. It’s as if they have a clock inside them, ticking along on a day that’s just a little shorter than 24 hours.

Even wackier was that roosters crow in order based on who’s the boss. Many animals have a “pecking order,” meaning they all know which bird, bear or gorilla is the biggest, strongest bully, and they stay out of that “top dog’s” way. Roosters all let the alpha rooster crow first, then the others crow in the right order. The system seems to work, but we’ll stick with our plug-in alarm clocks — at least they don’t shed feathers or peck at each other.

Wee ones: If 8 roosters have crowed, what number rooster crows next?

Little kids: Roosters actually crow about 2 hours before sunrise. If the sun rises in your town at 7:00 am, at what time would roosters crow there?  Bonus: Once the sun rises, how many hours pass until the rooster crows again the next morning? (Reminder: There are 24 hours in a day.)

Big kids: If 5 roosters — Roger, Redford, Rickles, Rupert and Ray — all agree to shuffle their order of crowing every day, from how many line-ups can they choose?  Bonus: If instead they assign numbers for pecking order 1 through 5, and Ray’s and Roger’s numbers added together and squared gives the same as Redford’s number squared plus 9, what numbers did those 3 roosters get? (One more piece of info: Ray’s number is smaller (better) than Roger’s.)

 

 

 

Answers:
Wee ones: Number 9.

Little kids: At 5:00 am.  Bonus: 22 hours.

Big kids: It will be 5x4x3x2x1, or 120 line-ups; once you choose 1 of the 5 for the 1st slot, you have 4 choices for the 2nd, then for each of those pairs you have 3 choices for the 3rd slot, and so on.  Bonus: You have 2 perfect squares that are 9 apart, so they have to be 16 and 25. So Redford got the number 4. Ray and Roger have to add up to 5, but they can’t be 1 and 4 since 4 already belongs to Redford. So Ray and Roger got the numbers 2 and 3, respectively.

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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 while still in diapers, 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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