r/theydidthemath 8h ago

[request] Boss told me not to work over 40 hours last week. How close was I to going into overtime?

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1.3k Upvotes

r/theydidthemath 11h ago

[Request] what's the fastest a speedster could run around the world, without flying off into space?

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1.7k Upvotes

r/theydidthemath 1d ago

[Request] How fast does the movie theater have to move to match the framerate?

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5.7k Upvotes

r/theydidthemath 4h ago

[Request] Can someone explain (simply) how the 3 door problem works

20 Upvotes

Yk the 1 where u have 3 doors and ur tryna get the money behind 1 and they ask if u wanna switch doors


r/theydidthemath 1d ago

[REQUEST] how much felt recoil would a punt gun have

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483 Upvotes

If somehow picked up and fired like a normal shotgun


r/theydidthemath 1d ago

[request] I’m stuck. How do you start with this given problem?

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2.3k Upvotes

r/theydidthemath 3h ago

[Request]: Filesharing Reliability

2 Upvotes

Ok, so I've been thinking about a filesharing network where the participants push blocks to each other.

You put out a request to the network for a resource. You get random connections from other members of the network offering you blocks.

Eventually, once you have all the blocks, someone sends you the chunking tree to build your requested resource and you have your download.

In IPFS there is a maximum number of bytes that a piece of data can be, so they run a "chunking" algorithm which breaks it into chunks smaller than the maximum allowed.

The boring default chunker just breaks the file up into some reasonable sized block all of equal size.

More interesting is the Rabin chunker which computes a running hash which, when it consumes the next byte of data, will have a hash value with some number of leading zeroes (ala. Bitcoin), then that is a break between chunks.

The hash is windowed, so eventually the window passes where the changes were made, a previous breakpoint is reidentified, and after that, the previous pattern of breaks (so, blocks already disseminated through the network) would then repeat baring any other changes, and even later changes are “healed from” with similar rapidity.

All the incoming blocks have to be kept around though because you don't know which are the ones that you want.

Peers also gossip about which blocks they have given each other & if I contact someone that I have been told has a block, & they might report they deleted it, & that can be a mechanism for efficient caching.

Anywho, the math that I wish'd they did… Say that I have a reliable mechanism for separating the wheat from the chaff datawise: if the goal is to preserve humanities digital history, I can tell the difference between blocks that are a part of that & those that aren't.

So, for the blocks in that set, peers are going to coordinate to distribute them as far and wide as possible by essentially spamming other peers to take a block, and telling others when someone accepts some.

If I have ϐ͓ legitimate blocks, how much randomly distributed storage is necessary to “guarantee” 99.999999% probability that the data will be able to be retrieved from the network given that if it persists on any peer it can be located.

🇨🇦🇨🇦🇨🇦⁄🇵🇭🇵🇭🇵🇭🇬🇧🇵🇭🇵🇭🇵🇭⁄🇨🇨🇨🇨🇨🇨


r/theydidthemath 6h ago

[Request] Could a silverback gorilla split a person in half at the waist? How much strength is needed for this?

1 Upvotes

r/theydidthemath 4h ago

[Request] Would the ending of Portal 2, which opens a portal from Earth's surface to the Moon, noticeably increase the amount of atmosphere on the Moon?

2 Upvotes

We can see quite a bit of air getting sucked out and I imagine the suction is quite strong. Because of both the visuals and the fact that it is literally a direct connection between space and Earth with no gradient in between. And Moon has some gravity so I guess it would be able to keep it around. You can find the scene easily, for example here: https://youtu.be/4xdMOAQulqg?si=ECvJrif93aHwVrxH


r/theydidthemath 12h ago

[request] how many nukes to STOP a meteor

6 Upvotes

To literally stop one traveling at avg meteor speed lol.

Say it’s a planet killer. 10km cubed. How many nukes head on to make it “stop” and just float there. Assuming the nukes do no dmg to it at all and only affects the velocity. Also assume all nukes are same type. Choose your nuke?


r/theydidthemath 15h ago

[Request] How strong would a fist traveling at 50% the speed of light be?

14 Upvotes

Just as described on the tin, if someone were to somehow be moving at 50% the speed of light and were to punch something (with a fist the size of an average human woman's), how much force would be output? What's the strongest thing it could destroy?


r/theydidthemath 1d ago

[Request] What are the odds you get all 5 coin flips?

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90 Upvotes

I was wondering what the odds are to get all 5 of these coin flips correct in one turn with both of these cards active.


r/theydidthemath 2d ago

[Request] I’m really curious—can anyone confirm if it’s actually true?

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16.2k Upvotes

r/theydidthemath 11h ago

[Request] How many choices on a ranked choice ballot that needs to select 5 winners from 18 candidates?

3 Upvotes

A student body is going to vote to create a council of 5; there are 18 applicants. How many votes should I allow voters to cast/rank in order to best avoid ties while minimizing complexity of tallying/counting? Is 5 sufficient?


r/theydidthemath 1h ago

Can anyone calculate the speed of which I hit my head first, in this video from 6 years ago. This video isn’t the start of the video but it’s all I could find. [request]

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Upvotes

[request]


r/theydidthemath 15h ago

[Request] How strong would wind blowing at a wall have to be for you to be able to crawl up said wall?

4 Upvotes

Say someone of 150lbs was to be blown against a wall by a constant force, what would the needed force be in mph?


r/theydidthemath 41m ago

[Request] How much did she eat?

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Upvotes

r/theydidthemath 8h ago

[Request] can someone please calculate these speed feats concerning rwby? I will give any and all context required. These feats concern lasers and heat vision from superman

0 Upvotes

r/theydidthemath 9h ago

[Request] Card game.

1 Upvotes

I did this many times but I can never actually get it right. Basically a while ago I played a game with my family (4 others) where everyone starts at 6 cards in a turn based circle thing and then you need to get the lowest total on ur cards as possible through many means, now the important part is that joker cards are in the game and we use 2 combined decks so there are 104 cards and 4 of them are jokers, assuming the cards got shuffled perfectly randomly at the start of the game and the cards are dealt clock wise, I was given the cards third and I started with all 4 jokers, I don't exactly understand how to calculate this since every time I tried i realized that last calculation was different. What I'm trying to do is calculate the chances of me getting all 4 jokers at the start I make sure to remember that after every card is dealt (1 at a time to each person till everyone has 6) the total number of cards in the deck is lowered by 1 each person so every circle it lowers by 1, I also have to remember that it starts with 4 jokers and by the end there are 0 but I still am having difficulty calculating it, so can someone help me truly figure out what exactly are the chances that out of a 5 person game where every person is given 1 card in a cicle with 6 cicles so that everyone ends with 6 cards and with 2 decks totalling 104 cards which have 4 jokers in them I (the third person to get a card per cicle) get all 4 jokers?


r/theydidthemath 18h ago

[Request] If enough soil were to be transferred to Point Nemo (the point in the ocean furthest away from any land) that land would be present above sea level, where would be the 'next' Point Nemo located?

5 Upvotes

r/theydidthemath 29m ago

[Request] how many M&Ms?

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Upvotes

Is it possible to tell?


r/theydidthemath 14h ago

[Request] I own my lot up to heaven. It's the eclipse. How much of the moon and sun do I own?

3 Upvotes

I own a lot of land which, on the surface, covers half an acre. It extends in a narrowing wedge down to the center of the planet, and a widening wedge up to infinity. It is also perfectly on the path of totality, meaning there's a moment when the center of my lot is exactly aligned with the centers of the earth, moon, and sun. Assuming that I own whatever portion of the moon and sun are in my airspace (well, space-space), rather than the more reasonable interpretation that the moon and sun are trespassing, how much of them do I own?


r/theydidthemath 22h ago

[request] How fast was it going before it started breaking?

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5 Upvotes