A beautiful international math olympiad problem

[jeremydarcangeli]

I wouldn't be able to compete even in the paralympic version of this

[KaramAlayan]

Please double it and give it to the next person

[wabalaka]

You know it's hard when a math problem doesn't have a single number in it

[PsyloAlpha]

POV math question requires more English language comprehension than the English one.

[funkyschnitzel]

I did quite a lot of math in my undergrad degree, and consider myself fairly competent.
If this question had been posed to me without the video we got here, I wouldn't even know what it was asking, let alone how to answer it.

[prasannabantu]

Mitochondria is the power house of the cell.

[tiffanytan]

Without the animation, I wouldn’t even understand the question.

No, I still don’t know how to approach the question anyway.

[Stepbrohelp]

I have a bachelors degree in pure mathematics, and I have absolutely no idea where to even begin with a question like this. The fact that actual children are able to solve these kinds of questions just blows my mind.

[mamtagrover]

My dumbass brain just thought of drawing the answer
Blowed up damn

[Shabudana]

Me after hearing the questions:
"Good question "

[moonmartex]

If you don't understand anything don't worry, the IMO is the final BOSS of math olympics and even a person with a decent math training would still struggle with this.

[Beanskiiii]

Humans that are really good at math are so cool

[mrbenwong]

I did this once in 1991, 2 days, 4.5 hours each, shit hard.

[joshbull]

Holy shit balls. Where would you even start with a problem like that!

[taizu]

Where's that random indian guy in comments claiming he already did this question in 4th grade? 😂

[youbigtubership]

I want to ask Alexa this and see if it melts down or explodes.

[geordiepunchingahorse]

What makes this problem special is that unlike most hard IMO problems (2023 P6, 2021 P2, 2020 P6) is that this problem has a relatively simple solution.

The solution is posted on their channel but it revolves around the idea that you draw a line pasing through one of the points and divide the plane into 2 parts. Notice that the number of points on each side does not change (other than a brief moment when the line passes through 2 points).

These kinds of questions with relatively simple ideas but little solves are dubbed “windmill effect” problems because of this problem. They usually have simple solutions that not many people will think of.

[chomumama]

Makes me think of the pen spinning in hand trick that bored students do in math class. Tips of fingers as points and the pen as the line, only the pen doesn't go exactly on the finger but its a good analogy for this problem.

[donspaceye]

There is one possible solution. If we can draw a graph satisfy the following 3 conditions, then this statement holds:
1. There should be an incoming edge and an outgoing edge for every node p. This outgoing edge must turn clockwise relative to the incoming edge of node p. The inward angle of this edge must be the smallest among all possible edges of p to its neighbors.
2. This graph must be cyclic, which means that the graph must contain a path that forms a loop. This path should be unique, which means that for every node in this graph, there should be exactly one incoming edge and one outgoing edge.
3. This graph must contain every single node in set S.
if for every set S, we could draw a graph that holds for the above 3 condition, than the statement in the question prompt holds.

[proisborn]

That is actually one of the most interesting maths problems i ever saw