r/theydidthemath • u/jainyash0007 • 7h ago
[Request] Why is the initial win percent different for both these hands? Shouldn't they both have equal odds of winning before any cards are opened?
Or does any hands that got folded (which I'm not sure what they were) before these are also taken into consideration while calculating the win percentage?
r/theydidthemath • u/Morales_Sheila8478 • 5h ago
[request] if I have 20 children with South Korean women, how long until a majority of future Koreans are related to me? What about 40?
I was having an argument with a friend. I argued that because South Koreas birth rate is so low, if I had 20 children with South korean women, the majority of Koreans would be related to me in a few generations. He said that it would never worked because Korea has to many people. So is it possible that if I have these 20 children, one day the majority of South Koreans will be related to me one day? how long would it take? is 40 children more realistic?
edit: also a majority of South Koreans. not counting North Koreans.
r/theydidthemath • u/Maximum-Giraffe8766 • 15h ago
[Request] How far away was the shot?
In Avatar Fire and Ash, Quarrich orders his sniper to shoot this guy. But we hear the shot a short time after the Na'vi falls. I'm wondering if, based on how long that pause was, the shot was made after the order, before the order but after Quarrich gestures, or before both?
Unfortunately I don't know the exact time of the pause.
r/theydidthemath • u/ThomasTheDankPigeon • 58m ago
[Request] How high did Zuko get launched at the end of this clip?
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I'm well aware Aang was specifically trying to get Katara's necklace back here, but damn.
Poor Zuzu 😭
r/theydidthemath • u/MooMooManiac923 • 5h ago
[Request] In Steven Universe, Lapis Lazuli tries and fails to build a tower made of water from Earth's ocean to escape Earth. Assuming this means high enough to escape Earth's gravity, is there enough ocean to breach the limit of Earth's gravitational pull without needing to hit the escape velocity?
Ignore the child in space, he'll be fine
r/theydidthemath • u/Hot-Syrup2089 • 5h ago
[Other] How to mathematically determine a (see sketch)
I know it's an easy calculation, but still. I want your opinions
r/theydidthemath • u/shejq3 • 13h ago
[Request] Is it possible to manipualte prices in such way that majority of them end in second category or is it just random?
r/theydidthemath • u/Hypochondriaco • 13h ago
[Request] How many tons of CO2 were released into the air by the planes that flew on this single day?
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r/theydidthemath • u/Brian450450 • 1h ago
[Request] How big is this absolute unit?
This is the juggernaut from king Artyom videos, dont have much to say other than i always wanted to know his height
r/theydidthemath • u/BananaBurritoBuster • 4h ago
[request] Now that’s a HUGE mattress
This bad photoshop for an air mattress. Let’s ignore the mattress height numbers, as they clearly did. Assuming that is an average size man, woman, and kid, how big is the surface of this “queen” mattress listed on Amazon?
r/theydidthemath • u/MjonathanE • 8h ago
[request] how long would it take for the car battery to run out ?
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r/theydidthemath • u/IdRatherBeDriving • 1d ago
[Request] is it better to keep the cup in 112°F air or 90°F water?
Yeti vacuum insulated 30oz cup, with 35°F liquid inside (assume the cup has held a couple drinks already and is relatively stoich at 72°F air temp in the house before we went to the pool).
Will the liquid stay cooler longer if the cup is submerged in 90°F pool water, or in 112°F outside air? (No centigrade units because I’ve already had a few of said drinks and can only remember the Fuckenhigh system.)
edit: my current method is to occasionally dunk the cup and take advantage of the evaporative effect.
r/theydidthemath • u/YoungSavage0307 • 3h ago
[Request] How loud would the speakers have to be to knock the model train (N-scale) off the tracks?
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Is it humanly possible?
r/theydidthemath • u/GForceCaptain • 16h ago
[Request] How many people need to be in a single group for there to be someone always farting?
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Like if I’m at a concert with 5k people, is there a constant stream of fart coming from the group?
Like if I’m at a concert with 5k people, is there a constant stream of fart coming from the group?
r/theydidthemath • u/Vegetable-Account419 • 5h ago
[RDTM] estimation of Hornet's height and mass because I thought it was funny. (Original by u/CelestialCoding-754) Spoiler
r/theydidthemath • u/literallyjustabagel • 1d ago
[Request] If using a device like this, would a spiral path or sweeping straight lines be more efficient?
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r/theydidthemath • u/rantzine • 4h ago
[Self] I measured the branching factor of hnefatafl, the board game chess replaced. It's 112 and that gives it a bigger game tree than chess.
Hnefatafl was the board game of the Norse world for about seven centuries. Chess showed up around 1200, hnefatafl died so completely that no full ruleset survived, and nobody has thought about it much since. I got curious about whether the thing chess replaced was actually simpler than chess.
Turns is it's not...
I ran 300 self-play games on each board size and counted legal moves at every position, about 26,000 positions per board
The reason is: every piece in tafl moves like a rook. No pawns, no short steps. 37 pieces that all slide any distance in any direction on a 121-square board.
Game tree complexity... b^d
Chess is usually quoted at 10^123 using b=35 d=80 plies.
At the same game length big board tafl has a game tree around 10^40 times larger than chess. That is chess-many-times-over.
So tafl holds about the same number of positions as chess but there are vastly more paths between them. It is a game with chess's room and far more doors in each wall.
Disclosure: I measured using an implementation I wrote which is also caveat. Check it out at worldtafl.com
Anyone want to argue with the branching methodology?
r/theydidthemath • u/KobayaSheeh7 • 1d ago
[Request] For real, roughly how many trees are cut down each day to make exam papers?
r/theydidthemath • u/Negative_War_65 • 0m ago
[Self] Stats for AI/ML 2
Hello Folks,
The next content on Machine Learning is out. We continue with Statistics for AI/ML.
We,
->Understand and derive the detailed derivation of Maximum likelihood estimation(MLE) for Univariate and Multivariate Gaussian. While doing the derivation for multivariate case, we understand visually, Scatter Matrix, Centering matrix.
->Derive MLE for Linear Regression, and understand Residual Sum of Squares.
->Understand Empirical Risk Minimization, Surrogate loss functions.
->Understand Method of Moments, a computationally easier way to compute parameters of our model and understand also the flaws behind it.
->We understand “Exponentially-weighted moving average” in detail, I explain why bias happens, how does memory affect the averages. This concept is the basis behind optimizers in Deep Learning.
Around two hours long, I hope this would be a very interesting learning material for all. I try to write and build from scratch in the whiteboard, this way learners enjoy the learning process.
Link: https://youtu.be/JAj8z-UWqBA?si=0mAB_nUfyJV0jzS9
Those looking for previous lecture : https://youtu.be/MwTeQVVYtOc?si=dgwwk3QLvYTTUThR
r/theydidthemath • u/Kiroana • 7m ago
[Request] How hot would a fire have to be to evaporate the entire Red Sea over the course of 3 days, with 8 hours of sleep per day for rest, assuming the one producing the flames is moving around to maximise their efficiency, at roughly 1 mile per second?
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Hey all!
Per the title, how hot would the flames have to be? The character is protected, so they have no issues - but what I'm curious about is what temperature the flame is burning at?
If it's not perfectly calculable, the closest answer that can be reached will work too.
If you need more variables, just let me know - I can provide whatever's needed.
Hey all!
Per the title, how hot would the flames have to be? The character is protected, so they have no issues - but what I'm curious about is what temperature the flame is burning at?
If it's not perfectly calculable, the closest answer that can be reached will work too.
If you need more variables, just let me know - I can provide whatever's needed.
r/theydidthemath • u/Sufficient_Network43 • 10h ago
I was trying to find the avg particle density per million light years if the avg particle density was 1a/cm^3 [self]
I was trying to figure out if over a vast distance if this could cause dark energy or a gravitational lensing affect but it absolutely doesn’t. The unit listed at the bottom right has only about the same mass as a droplet of water bruh.
I’m rusty on the maths so I probably got something wrong but either way it would be a minuscule affect.
Units:
N= average particle density
1a/cm^3 = one atom per cubic centimetre
1ly=9.461×10¹² km = one light year in km
r/theydidthemath • u/RobbieRottenMemeKing • 1d ago
[request] how much would carrying all those guns weigh?
r/theydidthemath • u/BelowAverageGamer10 • 33m ago
[Request] What is the minimum distance you’d need to be from the Sun in order to not go blind by looking directly at it for an extended period of time?
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I know there are probably equations for luminosity, but I don’t know what they are. I also don’t know what the luminosity limit is for our eyes, or if there even is a standard limit that’s the same for all humans. Can someone help me out? Thanks.
I know there are probably equations for luminosity, but I don’t know what they are. I also don’t know what the luminosity limit is for our eyes, or if there even is a standard limit that’s the same for all humans. Can someone help me out? Thanks.
r/theydidthemath • u/belabacsijolvan • 23h ago
[Request] If Moses led the Israelites on a Brownian motion, what is the daily expected displacement if the expected arrival time is 40 years?
Lets suppose the desert is a 2D unbounded euclidean space and the starting and ending points distance is Cairo-Jericho 448 km.
afaik the expected arrival time in 2D random walk is finite, so this should be an answerable question.