Explain xkcd: It's 'cause you're dumb.
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| Dental Formulas |
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Title text: I mean, half of these are undefined. And your multiplication dots are too low; they look like decimal points. |
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Explanation
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This is incomplete:
This page was created by your new dentist, who has a pure math background. Don't remove this notice too soon. If you can fix this issue, edit the page!
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A dental formula specifies the number of teeth of each type on each side of the jaw for a given species, with dots separating the numbers. There are two rows, representing the upper and lower jaw, separated by a horizontal line. The number of incisors is indicated first, canines second, premolars third, and finally molars, so the formula in the comic would represent 3 incisors, 1 canine, 3 premolars, and 1 molar on each side of the upper jaw, and equal numbers in the lower jaw except only 2 premolars. This is the dental formula for the cat family. The adult human dental formula is 2.1.2.3 for both the upper and lower jaw.
Cueball is (wrongly) treating a dental formula as an arithmetic expression, with the line indicating division and the dots indicating multiplication. In the title text his statement that half the formulae are undefined refers to animals that lack one of the four types of teeth in the lower jaw, leading to a zero in the "denominator" of the dental formula and an undefined division expression. He also notes that the "dots are too low", as in fact the dots in a dental formula are period characters and aren't meant to imply multiplication, which uses middle dot characters.
The word 'mammologist' is an alternate spelling of 'mammalogist', for one who studies mammals. Or, in some cases, specifically studying the mammaries (i.e. breasts) which mark out mammals in general. The specific study of teeth might be termed 'odontology', so we should assume that the experts who Cueball is referencing are not specifically tooth-focused, merely using this particular specialism to help with their own particular, arguably far wider, brief that is not so entirely fixated solely upon any particular body parts.
Transcript
- [Cueball and Megan are standing in front of a whiteboard, on which is written
- 3.1.3.1
3.1.2.1
- along with a drawing of a tooth and some other scribbles.]
- Cueball: Do mammologists think these are hard?
- Cueball: I mean this one just evaluates to 3/2.
- [Caption below the panel:]
- Mathematicians encounter dental formulas
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This is a test. PoolloverNathan[stalk the blue seas] 20:48, 16 March 2021 (UTC)
- This is not. —While False (museum | talk | contributions | logs | rights | printable version | page information | what links there | related changes | Google search | current time: 17:40) 18:38, 17 November 2022 (UTC)
- A foreign student asked me to help fight against his math teacher. That was unusual. He was in that class for just a couple of weeks. The teacher's phone number was sent to me. The student asked me to spam-call the teacher. 172.71.155.55 22:58, 18 September 2023 (UTC)
here i'm just messing around in html, ignore this
furhhfghure guyrburgryhuyvfr "rvhru"
interesting way of writing quotations xd
- hmmm this one of putting "<p>" in a line break will come in handy for when i want it to start at the same place than the first line
- Please beware that <p> on mediawiki also disables automatic paragraph breaks, so you need a closing </p> or you'll break automatic paragraph formatting for the rest of the page. Zmatt (talk) 22:06, 31 July 2024 (UTC)
edit: da hek did that "</div>" come from An user who has no account yet (talk) 14:14, 13 October 2023 (UTC)
hi uh its hard to get here.
is this a reference to undocumented feature??? hmm... this is interesting.
108.162.241.216 02:05, 23 November 2023 (UTC)
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yum yum [citation needed]
Hiuiedeixgeyceiyedhcdiedcve
{{trout}}
This is the leaderboard:
<a href=" [AT THE JULY 28TH MEETING][tab] "Cancel the meeting! Our cover is blown.">
More testing: hello doesthiswork (yesitdoes) This isn't a good name (talk) 22:44, 28 January 2026 (UTC)
hi
164.58.172.158 14:21, 23 February 2026 (UTC)
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