this post was submitted on 19 Jun 2025
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Math Memes

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Memes related to mathematics.

Rules:
1: Memes must be related to mathematics in some way.
2: No bigotry of any kind.

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[–] vaguerant@fedia.io 152 points 2 weeks ago (11 children)

I understand why this is wrong (order of operations dictates the division happens first, so it's really 25 - 1 = 24), but why is it funny? I don't mean "This isn't funny," I think I'm just missing the joke.

[–] Thekingoflorda@lemmy.world 398 points 2 weeks ago* (last edited 2 weeks ago) (4 children)

4! Is meant to be 4 factorial. 4! = 4 x 3 x 2 x 1 = 24

[–] vaguerant@fedia.io 121 points 2 weeks ago

Aha! Got it, thank you so much.

[–] Eyedust@lemmy.dbzer0.com 41 points 2 weeks ago

And here I was thinking I was still decent at math. I got bamboozled...

[–] jaybone@lemmy.zip 15 points 2 weeks ago

Or if you don’t know order of operations, then you probably also don’t know factorials, so 20 / 5 = 4

[–] Psythik@lemmy.world 6 points 2 weeks ago* (last edited 2 weeks ago) (4 children)

The fuck is a "factorial"? They didn't teach me that one in high school math and I couldn't afford college.

[–] Dearth@lemmy.world 17 points 2 weeks ago (4 children)

Im sorry your highschool curriculum failed to teach you. I learned factorals in jr highschool

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[–] BreadstickNinja@lemmy.world 14 points 2 weeks ago* (last edited 2 weeks ago) (5 children)

Factorial means n! = (n)(n-1)(n-2)... etc. down to 1, where n is a positive integer. It's used to calculate the different number of configurations of a set of elements, mainly in combinatorics.

Like if you have four different objects and you want to know how many different configurations you can order them in, you have four choices for the first object, then three for the second, then two for the third, then one for the final slot. So the answer is 4 x 3 x 2 x 1 = 24 = 4!.

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[–] ArrantKnave@lemmy.world 19 points 2 weeks ago

4 factorial

[–] bleistift2@sopuli.xyz 17 points 2 weeks ago

The exclamation point denotes the factorial function. 4! = 4 ⋅ 3 ⋅ 2 ⋅ 1

[–] Zorque@lemmy.world 14 points 2 weeks ago

I see no one has explained yet, so I'll give it a shot. He is excited about math, and that needs to be encouraged.

[–] Mastema@infosec.pub 12 points 2 weeks ago* (last edited 2 weeks ago)

The exclamation point makes it right. The formula, when worked with proper order of operations, equals 24, which is equal to 4 factorial (4!) 1 * 2 * 3 * 4=24

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[–] stebo02@sopuli.xyz 128 points 2 weeks ago
[–] bleistift2@sopuli.xyz 82 points 2 weeks ago

Best math meme so far.

[–] HEXN3T@lemmy.blahaj.zone 48 points 2 weeks ago (1 children)

4! = ...Wait, that's literally the point of the post this time

[–] four@lemmy.zip 28 points 2 weeks ago (3 children)

Unexpected expected factorial

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[–] pixeltree@lemmy.blahaj.zone 30 points 2 weeks ago (2 children)

Comment section full of people looking for an opportunity to argue

[–] abbotsbury@lemmy.world 50 points 2 weeks ago (1 children)
[–] petrol_sniff_king@lemmy.blahaj.zone 19 points 2 weeks ago (3 children)

Yes it is

Wait, will this be the 5-minute or the half hour?

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[–] j4k3@lemmy.world 29 points 2 weeks ago (2 children)

ASCII hack failure of language. Even in mathematics, ! has multiple meanings like with Boolean NOT. We need a science, math, and language reformation to remove non intuitive narcissistic names, and implied contextual meanings.

[–] davidgro@lemmy.world 20 points 2 weeks ago* (last edited 2 weeks ago) (3 children)

You might find Lojban interesting if you are not already aware. (I haven't tried to learn it myself, I just know it exists)

[–] MBM@lemmings.world 7 points 2 weeks ago (1 children)

I've never seen ! used for boolean NOT in maths, just ¬. I think ! is something programming languages went for because it's easier to type. That said, screw (a, b). Is that a (coordinate) pair, an interval, an inner product, some secret fourth thing? Who knows!

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[–] faythofdragons@slrpnk.net 28 points 2 weeks ago

You got the wrong symbol in the headline, it should be >3

[–] faltryka@lemmy.world 26 points 2 weeks ago

Ok this is funny

[–] blind3rdeye@lemm.ee 24 points 2 weeks ago* (last edited 2 weeks ago)

This is quite possibly the best maths joke I've ever seen.

[edit] I guess it still can't beat the 'be rational' / 'get real' one.

[–] gofsckyourself@lemmy.world 20 points 2 weeks ago

Thank God this meme is muted

[–] ShadowRam@fedia.io 20 points 2 weeks ago (1 children)
[–] expatriado@lemmy.world 12 points 2 weeks ago

for those that didn't get it: clever factorial = brilliant

[–] workerONE@lemmy.world 7 points 2 weeks ago* (last edited 2 weeks ago) (1 children)

Promptly Evacuate Manure Drain And Septic

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[–] Sir_Premiumhengst@lemmy.world 6 points 2 weeks ago (2 children)
[–] Lifter@discuss.tchncs.de 7 points 2 weeks ago* (last edited 2 weeks ago)

4 != 24 but also

4! = 24

4! = 5-5/5

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[–] dontbelievethis@sh.itjust.works 6 points 2 weeks ago (1 children)

Can someone explain to me why this is funny?

[–] ramble81@lemmy.zip 30 points 2 weeks ago (1 children)

So with people who do order of operations incorrectly, you have 25-5 =20 and then divide it by 5 and you get 4.

However the correct answer is 24 since you do the division first.

Where the joke comes in is he states “4!”, which sounds like he is emphatic about the wrong answer. However an exclamation mark is “factorial” which translates to 4x3x2x1… which happens to equal the correct answer of 24.

[–] dontbelievethis@sh.itjust.works 8 points 2 weeks ago

Ah! :D I like it.

[–] uriel238@lemmy.blahaj.zone 6 points 2 weeks ago* (last edited 2 weeks ago) (2 children)

25 - ⁵/₅ = 25 - 1 = 24

If you wrote it vertically:

25 - 5
————— = 4
5

But once you lay it out on one line, you have to use prins to prioritize addition / subtraction:

(25 - 5) / 5 = 20 / 5 = 4

Some YouTube mathematicians deep-dive into this.

ETA: Nothing goes over my head! My reflexes are too fast, I would catch it.

[–] JackbyDev@programming.dev 55 points 2 weeks ago (1 children)

The joke is 4! (Factorial) Is 24 so it looks right even if you do order of operations incorrectly.

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[–] SkunkWorkz@lemmy.world 8 points 2 weeks ago

Yeah and 24 = 4 factorial = 4!

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