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Durtles

@makeaproblem.bsky.social

67 followers 50 following 260 posts

Math book author and problem collector. Books: https://dandelioneducation.ca/books/ YouTube: https://www.youtube.com/@MakeaProblem

dandelioneducation.ca

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Durtles @makeaproblem.bsky.social · Sep 2

Aight, in an attempt to make #MathSky feel less broadcast-y and more community-like (inspired by @jjnevis.com ), let's try an intro post. Drop your answers below:
1. What part of the world are you in?
2. What's your favourite math branch/topic/problem and why?
Say hi to those with similar answers.

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Durtles @makeaproblem.bsky.social · 15d

I just realized I do the pokemon thing but for math problems. 🤔 I catch them and "train" them until they evolve into a book or a video. 😅

Durtles @makeaproblem.bsky.social · 18d

I made this week's problem into a video too.
youtu.be/elp1RSD8Tq4
Sorry to take another break from the posting schedule so soon, but we have a family trip coming up. See you again in a month or so. ☺️
#math #maths #ProblemSolving #iteachmath #MathSky

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Durtles @makeaproblem.bsky.social · 19d

f). How many different arrangements of the name cards for n people (where n is odd) are there that have this property?
#math #maths #ProblemSolving #iteachmath #mathsky

Durtles @makeaproblem.bsky.social · 20d

e). Prove or disprove that no arrangement of name cards work for even numbers of people.
#math #maths #ProblemSolving #iteachmath #mathsky

Durtles @makeaproblem.bsky.social · 21d

d). Prove that the reverse order arrangement of name cards always work for odd numbers of people.
#math #maths #ProblemSolving #iteachmath #mathsky

Durtles @makeaproblem.bsky.social · 21d

🤯 OEIS really does have everything under the sun! 😂

And look, you found all the ones for 7 people!

Durtles @makeaproblem.bsky.social · 22d

Oooo... What are the others you found, if you want to share?

Durtles @makeaproblem.bsky.social · 22d

Oh interesting! I was wondering if there are irregular ones and was tempted to hunt down a coder somewhere to do a brute force search for me. XD. How are you finding these?

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Durtles @makeaproblem.bsky.social · 22d

That was my guess for 7 too until Everett here broke the illusion. XD

Durtles @makeaproblem.bsky.social · 22d

c). How many different arrangements of the name cards for 4 people are there that have this property? 6 people? 7 people?
#math #maths #ProblemSolving #iteachmath #mathsky

Durtles @makeaproblem.bsky.social · 23d

I made these books for my own kids. If you're a math problem enthusiast and have a child in your life with whom you want to share that love of math, feel free to check them out.
mybook.to/hTtGl
#mathsky #iteachmath #math #maths #ProblemSolving #MarketingMonday (I hesitated, so it's not Monday..)

Durtles @makeaproblem.bsky.social · 23d

b). How many different arrangements of the name cards for 5 people are there that have this property?
#math #maths #ProblemSolving #iteachmath #mathsky

Durtles @makeaproblem.bsky.social · 24d

Oh I haven't noticed that at all! That's very interesting.

Durtles @makeaproblem.bsky.social · 24d

(Different arrangement of name cards I mean. Ran out of characters there.)
#math #maths #ProblemSolving #iteachmath #mathsky

Durtles @makeaproblem.bsky.social · 24d

Happy Monday! This problem is inspired by the 1975 CMO Q6ii
Here are 5 people at a meeting. Notice if we place their name cards in reverse order, no matter how we turn the table, only one person will have the right name card at any time.
a). Find a different arrangement for 5 people like this.

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Durtles @makeaproblem.bsky.social · 25d

So I made a video on this week's problem too.
youtu.be/zYsNc0oJKo8
#math #maths #ProblemSolving #iteachmath #mathsky

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Durtles @makeaproblem.bsky.social · 26d

f). How many different arrangements of mismatching all name cards are there for n people around the table? (rotating the table counts as the same arrangement)
#math #maths #ProblemSolving #iteachmath #mathsky

Durtles @makeaproblem.bsky.social · 27d

e). How many different arrangements of mismatching all name cards are there for 5 people around the table? (rotating the table counts as the same arrangement)
#math #maths #ProblemSolving #iteachmath #mathsky

Durtles @makeaproblem.bsky.social · 28d

d). How many different arrangements of mismatching all name cards are there for 4 people around the table? (rotating the table counts as the same arrangement)
#math #maths #ProblemSolving #iteachmath #mathsky

Durtles @makeaproblem.bsky.social · 29d

c). For which numbers of people is it always possible to rotate the table such that at least 2 people have the right name cards if they all start out mismatched?
#math #maths #ProblemSolving #iteachmath #mathsky

Durtles @makeaproblem.bsky.social · Sep 9

b). With 5 people at the meeting, sketch a way to place the name cards such that they’re all mismatched. Can you always rotate the table such that at least 2 people have the right name cards?
#math #maths #ProblemSolving #iteachmath #mathsky

Durtles @makeaproblem.bsky.social · Sep 8

Is there a website where I can read about Making Space? I'd love to learn more. ❤️

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Durtles @makeaproblem.bsky.social · Sep 8

have to somehow teach the students to come up with their new original problem every time we run a Math Fair (which also means the adults have to know how to do it first...). I'd love to hear your ideas (and anyone else reading this convo, like @maria-naturalmath.bsky.social 😉)!

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Durtles @makeaproblem.bsky.social · Sep 8

It's one of my long time dreams to figure out a sustainable way to run Math Fairs at scale with a constant stream of new problems. We'd have to have a global community of adult recreational math problem collectors/makers (like how a creative writing community supplies endless new stories), or we'd

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Durtles @makeaproblem.bsky.social · Sep 8

problem pool, and also static (no new problems added regularly). There's the official website up there, and there's the list on the galileo website:
galileo.org/math-fairs/m...
which resulted in visitors getting tired of the problems after 2 or 3 years (the students were new to them each year).

Math Fair Problems - Galileo Educational Network

A Math Fair is a non-competitive problem solving event that gives teachers an opportunity to have their students do problem solving with a particular goal…

galileo.org

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