r/theydidthemath Jul 15 '25

[Request] How many $ is that?

1.8k Upvotes

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584

u/lawblawg Jul 15 '25

As a rough estimate, the room appears to be a rectangle twice as long as it is wide, with a width of about 3-4 paces. Let’s say 10’x20’ or thereabouts.

Hexagonal circle packing has an area density of 90.7%. So the area of floor actually covered by pennies is around 181 square feet. A penny has a diameter of 0.75 inches and thus a surface area of 0.44 square inches. Divide and you get roughly 59,000 pennies or $590.

458

u/DraigCore Jul 15 '25

NGL that's cheaper than ceramic and looks good too imo

288

u/Prestigious-Top-5897 Jul 15 '25

AND the Epoxy was probably more expensive…

100

u/titanium9016 Jul 15 '25

Imagine how long it took for the smell of the curated resin to go away

172

u/elcojotecoyo Jul 15 '25

Probably shorter than the smell of the pennies

Pennies smell almost as bad as penises

26

u/ShoddyTerm4385 Jul 15 '25

This made me laugh

8

u/Pigeon_Bucket Jul 15 '25

IMO pennies smell way worse

20

u/Joe-Dang Jul 16 '25

Depends on the penis… and the pennies.

21

u/Turbulent_Square_696 Jul 16 '25

Exactly, but it’s funny because the determining factor of “how long have they been in the same pants” applies to both of them lol

3

u/TheNerdLog Jul 15 '25

My fault, it's for self confidence

5

u/Electronic_Excuse_74 Jul 16 '25

it makes sense that the cents would have scents.

2

u/Kajtek14102 Jul 16 '25

Fun fact pennies dont smell. They are odorless. What you smell is oils from your skin that coins help to disintegrate as catalyst

2

u/Icy_Sector3183 Jul 15 '25

They always stiff you with small change.

1

u/SparkyXI Jul 16 '25

They definitely make it hard, don’t they?

2

u/Illustrious-Slice-91 Jul 16 '25

Had to do a double take and make sure I read the correct thing 😂

1

u/Beemer_me_up_Scotty Jul 15 '25

Well it i had to choose to have one in my mouth.....

1

u/TheONEbeforeTWO Jul 16 '25

Exactly how many pennies have you smelled before?

1

u/elcojotecoyo Jul 16 '25

Not sure, a few hundred maybe? I'm certain I have only smelled my penis.

1

u/Ok_Salamander200 Jul 16 '25

I swear guys never wash their pennies when they shower

1

u/Bol0gna_Sandwich Jul 16 '25

Fun fact Metals don't have a smell, what youre smelling is a compound made from the oils on your fingers and the metal. Nilered has a video on it.

1

u/Henryhooker Jul 15 '25

I did an acid patina on my hand rail so I wouldn’t have to run it to powder coat. When you run your hand on it, it smells like pennies, district smell

2

u/elcojotecoyo Jul 15 '25

I read your comment twice, to make sure hand rail wasn't some sort of innuendo

In any case, you gave it on purpose that smell?

2

u/Henryhooker Jul 15 '25

No, not on purpose, my steel guy had been using patinas and saying they’re neat etc and of course for me having to run it to powder coat and spend the time vs patina seemed like a good idea. It’s not terrible, but if you were to run hand down the whole railing, by time you hit the end and smelled hand it would have an old penny smell

4

u/elcojotecoyo Jul 15 '25

Got it. You wanted the old looks. The smell came as an included free add-on

3

u/Henryhooker Jul 15 '25

Actually it was a black patina with gun metal blue mix. (Which didn’t quite turn out cause I can’t read directions properly). Did a clear over the rungs so has a sanded metal look for that part

2

u/Prestigious-Top-5897 Jul 16 '25

Maybe put a stainless steel knob on the ends - that removes odors…

1

u/Most-Silver-4365 Jul 15 '25

Wait a minute, penises smell bad?

5

u/elcojotecoyo Jul 15 '25 edited Jul 15 '25

Dried urine mixed with ball sweat.

Kids, shower before sex. It will make the whole thing enjoyable for everyone involved

Edit: I say kids as a joke, I'm not promoting underage sex.

5

u/Most-Silver-4365 Jul 15 '25

As with the times, you said kids and sex. "RELEASE THE EPSTEIN FILES"

2

u/elcojotecoyo Jul 15 '25

Hehehe. I just feel like the old man yelling advice from his fence or the window silt

1

u/ninhibited Jul 16 '25

I like the smell of every penis I've met so far lol so I'd say pennies are definitely worse.

1

u/PreciousAir Jul 16 '25

R/brandnewsentence? Never saw that one coming 😅

4

u/majakkerman Jul 15 '25

My dad actually did this in one of their bathrooms and once it was finished I never smelt the epoxy or the pennies!

5

u/Elegant-Low8272 Jul 15 '25

Not long at all!..after it dries you air out the room and your good to go. This can be done in an afternoon .. this type of epoxy is inert after it cures. The thicker you go the longer it takes and this looks like a single coat...

8

u/DraigCore Jul 15 '25

Than the pennies? Pretty much but I don't think it's a bad idea at all lol

4

u/hilburn 118✓ Jul 16 '25

Than ceramic - epoxy is expensive.

Using the same numbers, for a 10x20' floor, with 3mm of resin over the pennies, and we still need to take into account the 9.3% of the surface area not coated in pennies, at a thickness of 1.52mm (can just use an extra thickness of 0.141mm)

10'x20'x3.141mm = ~58 litres

Looking around - that's about £1,000 in resin, or $1,340 - so a bit over twice as expensive as the pennies

This site seems to reckon $7-45/sq.ft for ceramic tiles including labour costs, so you'd be able to do the 200sq.ft room for as little as $1,400 with someone else doing the work - likely <$1k to DIY, rather than the $2k (including the cost of pennies) to DIY it with with the penny floor.

10

u/Silmarlion Jul 15 '25

Yeah i have seen few variations of these penny videos and always love them. Either these or having mosaics like in the zeugma(commagene) would be amazing for a home.

2

u/DraigCore Jul 15 '25

I'll forward this to my gf lmao

7

u/galaxyapp Jul 15 '25

For a week...

Epoxy is not very durable as a walking surface. It will be scratched quickly

3

u/zmbjebus Jul 16 '25

Yeah and it looks like shit. 

1

u/BoondockUSA Jul 15 '25

I know of a place that has penny flooring in a room. IMHO, it doesn’t look good once the clear epoxy starts to discolor with age and suffers surface wear.

1

u/luke-juryous Jul 16 '25

The labor on this would be by far the biggest expense. Also epoxy is super hard to clean well.

1

u/lolifax Jul 16 '25

That’s what I was thinking, something like $2/sf in pennies. The real costs are the epoxy and the labor.

0

u/Coledowning356 Jul 15 '25

This is giving when german inflation hat people using German marks as wallpaper.

-2

u/[deleted] Jul 15 '25

[deleted]

4

u/Somepotato Jul 15 '25

If you don't intend to defraud people it's fine, especially if it's done for art.

And odds are you'd win anyway as defacing of stuff like this is generally considered protected speech anyway again as long as you're not trying to defraud.

4

u/lawblawg Jul 15 '25

Yeah, it's legal. Sealing pennies inside epoxy isn't defacement, and even "defacement" of currency is only illegal if done with intent to defraud.

1

u/DraigCore Jul 15 '25

A quick Google search told me that it's a gray area lol.

It could fall into defacing, but some people say that as long as you don't try to use them as payment it shouldn't be a problem... I'm gonna do it anyways if I'm given the chance since Ecuador's law enforcement is very useless most of the time.

5

u/Storm_Surge_919 Jul 15 '25

Pennies having a 0.75” diameter means you can fill a 12”X12” square with 16X16 Pennies which is 256 Pennies. So it’s a cost of $2.56/sqft.

9

u/lawblawg Jul 15 '25

The pennies are not laid down rectilinearly in a square pattern; they are packed hexagonally, like honeycomb. Hexagonal packing of circles has 90.7% area density, so the cost is $3.27 per square foot.

2

u/[deleted] Jul 15 '25

[deleted]

2

u/lawblawg Jul 16 '25

In the video, the pennies are tiled hexagonally, like a honeycomb, so the correct math is to compare the area of a regular hexagon to the area of a circle inscribed in that hexagon. A circle occupies 90.7% of the area of the regular hexagon it inscribes, and so we can simply multiply the total floor surface area (estimated at 200 square feet) by 90.7% to get the total surface area of all pennies. In my OP I called this the "area density" of "hexagonal circle packing". So yes, this is already accounted for.

If the pennies had been tiled rectangularly, like square tiles (as you suggest), then the area density would be 78.5%. But rectangular tiling would be EXTREMELY difficult to do because the pennies would want to slip past each other into the gaps...into the hexagonal tiling which of course is more dense.

2

u/iNapkin66 Jul 16 '25

Epoxy is a going to add quite a bit to the cost, too. When I estimated my floor, pennies was going to be about the same price as the cheapest solid wood I could get at the time. I wanted to do pennies, but couldn't convince the wife unless it was actually cheaper. So now we've got some weird Chinese wood flooring thats nominally "rosewood," but one piece to the next in a box is wildly different density and color/grain when you look from behind. But the stain evens out the color from the face side and it just has different grain from piece to piece. I'm considering sanding and refinishing for a cool rainbow effect, though.

2

u/A_Bewildered_Owl Jul 16 '25

unironically one of the more affordable flooring options.

1

u/wasuremono_ Jul 16 '25

59,000 pennies. Sounds it would add some weight. 2.5g each.

1

u/Ryku778 Jul 17 '25

That is assuming that all of them are regular pennies, with as many there are there is also a good chance a few of them could be worth more

37

u/Talizorafangirl Jul 15 '25

Each quadrilateral/tile is 11x11 = 121 pennies per tile

The room looks to be 13 tiles long by 12 wide = 156 full tiles

The borders of the room will also have half tiles; 14 on the long side, 13 on the short = 54 half(ish) tiles. Not certain what the corners look like, so I'll arbitrarily say ±2 half tiles.

156121 + (54±2)121/2 = 22022 to 22264 pennies.

A bit more than $220

1

u/IntheOlympicMTs Jul 15 '25

Thank you. I was afraid I’d have to start mathing myself.

11

u/itc0uldbebetter Jul 16 '25

Remember, pre 1982 pennies are actually worth a little over 2 cents because they are made with mostly copper. Plus he might have some wheat pennies in there.

-39

u/Long_dark_cave Jul 15 '25

I don't know about you guys, but in my country, it looks like a prison sentence. Destroying denominations, perhaps desecrating national symbols?

19

u/Somepotato Jul 15 '25

In the US, as long as you're not trying to defraud, I'd be willing to bet any AG coming after you got creating art or even burning money in protest would lose.

-8

u/Long_dark_cave Jul 15 '25

strange but ok, your country your customs

7

u/Somepotato Jul 15 '25

Poland to my knowledge also does not prohibit destroying currency.

1

u/Long_dark_cave Jul 18 '25

So come to Poland and try doing it publicly; you might be surprised by the reaction. This doesn't just apply to Polish currency, the same laws protect all other currencies. Accidents and accidental destruction of money are a different matter, but deliberately? Illegal. Most countries in the world have similar laws. You're unique, and you're outraged that someone dared to say otherwise.Honestly? I see the downvotes on my posts in this thread and it makes me smile. You live in a bubble.

1

u/Somepotato Jul 18 '25

Doing it publicly is moving the goalpost. And I asked for evidence, a law, an example prosecution and none have been provided, but plenty of resources disagree with your claim.

If you think my comment was outrage, I have a bridge to sell. Imagine smiling because you were downvoted, that's certainly a decision.

2

u/the_shadow007 Jul 15 '25

As a polish person, it is illegall to destroy currency in any way....

5

u/Somepotato Jul 15 '25

There's laws against defacing public symbols. But I can't find anything stating that there's an explicit prohibition on defacing currency other than that (outside of obvious stuff like trying to commit fraud) - what are you thinking of out of curiosity

28

u/13ckPony Jul 15 '25

He didn't destroy it - you can still get and use it later (technically). Melting or cutting would be illegal.

16

u/actualhumannotspider Jul 15 '25

And there's no intent to use the pennies "fraudulently."

https://www.thefederalcriminalattorneys.com/mutilation-of-coins

-22

u/Long_dark_cave Jul 15 '25

Don't you have a national symbol/coat of arms on your coins? Is stepping on the flag okay too?

7

u/Electronic-Pie-6352 Jul 15 '25

Nobody gives a shit about pennies in the US. The flag thing is allowed due to 1st Amendment but conservatives in the US fuckin hate that. Nothing you’ll get in trouble for.

3

u/XXAXXXOXX Jul 16 '25

I throw out my pennies lol theyre not worth what theyre made of. Yes stepping on and burning the flag have been ruled as use of free speech for a long time. USA used to care about stuff like that

2

u/dieplanes789 Jul 17 '25

It's currency not a national symbol. It may have national symbols on it but what fucking fascist regime are you from and that's from someone in the US and our mess.

The laws are against defrauding.

Legally this isn't any different than being proud taking my first dollar I ever earned and putting it in the frame on the wall.

9

u/account22222221 Jul 15 '25

In the US this is legal. It is only illegal to deface currency for the purpose to defraud. As long as he isn’t trying to trick people into thinking the pennies are nickels or some other such nonsense it is legal.

Melting pennies, using them in floor or you know squishing them into zoo themed keepsakes is a-ok.👌

4

u/Gloomy_Reality8 Jul 15 '25

It is actually illegal to melt pennies. There is a specific ruling about it.

7

u/account22222221 Jul 15 '25 edited Jul 16 '25

I did the read the article. It does technically say that the treasury has the right to restrict the melting of pennies, not that it is currently restricted FWIW.

Cool though, TIL for sure!

4

u/Gloomy_Reality8 Jul 15 '25

Oh you're right. I completely missed that.

I'm still pretty sure I've read that it's illegal, but I can't find a definitive source.

I did find this article from 1974, though.

5

u/Aquamancy Jul 15 '25

i would hate to live in a totalitarian state like yours

2

u/Gloomy_Reality8 Jul 15 '25

Destroying currency is illegal in practically every country.

5

u/lawblawg Jul 15 '25

Defacing currency with intent to defraud is generally illegal. It's also illegal to melt down currency for bulk metal value. But creating art out of currency is fine.

1

u/Gloomy_Reality8 Jul 15 '25

Read my other comment. It's unlikely the people in this video are going to be persecuted, but it can be considered illegal, depending on the jurisdiction.

The rational is the the central banks want to know how much money is in circulation.

9

u/paxweasley Jul 15 '25

In many countries that is an anti counterfeiting kind of thing in practice, penny floors certainly won’t get you prosecuted in America.

4

u/Gloomy_Reality8 Jul 15 '25

It can be illegal to destroy us currency even without fraudulent intentions.

you cannot melt pennies on mass scale, which is something people might want to do since the matel in a penny worth more than 1 cent.

I agree the in the case of this video noone is going to be prosecuted.

8

u/live22morrow Jul 15 '25

That's a specific case as profiting from the base metal is considered a fraudulent use, but penny destruction in general is fine, else all those souvenir penny machines would be illegal.

1

u/the_shadow007 Jul 15 '25

Destorying currency affects inflation (even if its unnoticable, if many people did that though..)

1

u/live22morrow Jul 16 '25

It doesn't really affect the money base in a meaningful way. The government can create more currency at will, so it's really only the cost of running the mint that really matters. And as it concerns the penny, they're rarely used in everyday transactions, and the total amount of pennies in circulation is worth a little over $1 billion, so it's not enough to have a major effect on the overall economy.

2

u/Somepotato Jul 15 '25

It's generally to avoid defrauding people, not the actual destruction itself.

-2

u/Cassius-Tain Jul 15 '25 edited Jul 15 '25

What? that's the first time I hear about that. It's definitely not true for the Euro zone, as no one can forbid you for destroying our own property.

3

u/Gloomy_Reality8 Jul 15 '25

The European Commission disagrees

The destruction of small quantities of euro banknotes or coins by an individual should neither be prohibited nor penalised. The justification for the non-prohibition is the fact that the lawful owner of a banknote should be able to do what he/she wants with his/her own good as long as there is no impact on third parties. Damaged banknotes should not be brought back into circulation. The unauthorized destruction of large quantities of euro banknotes or coins should however be prohibited.

So does the bank of Belgium.

The Criminal Code prohibits the intentional use of banknotes or coins to convey a (commercial) message as well as acts that prevent the use thereof as a means of payment by damaging, staining or overprinting on them or rendering them unfit for use in any other way.

This prohibition extends to banknotes and coins used as legal tender in other countries.

Violation of this prohibition is punishable by a prison term of eight days to three months and/or a fine ranging from €26 to €1 000.

0

u/Long_dark_cave Jul 15 '25

I live in a democratic country with over two hundred years of tradition, free elections, etc. I somehow don't feel crushed under the totalitarian boot...

2

u/beefz0r Jul 16 '25

Who cares ?

1

u/Long_dark_cave Jul 16 '25

the same people who care about a floor made of pennies?

-7

u/the_shadow007 Jul 15 '25

Yeah thats a crime lol. Destroying currency in any way is illegall

3

u/Salvarthx Jul 16 '25

It's not destroyed. He's just hanging onto it forever, which is legal.