Seems like they're not, although I get your thought process. If we take Old English (which was English before the Norman conquest) and modern Swedish (since Sweden was never conquered by anyone from France or the Romans) as comparisons, we have

Eleven: OE endleofan, Swedish elva Twelve: OE twelf, Swedish tolv Thirteen: OE threotiene, Swedish tretton Fourteen: OE feowertiene, Swedish fjortun

I think you can see the pattern. These actually all have similar common ancestors going into Proto-Germanic, so they're way older than the French influence on English.

Since other Indo-European languages like German and Russian do the same thing as English where the line between "one word numbers" and "two word numbers" is 20 to 21, I suspect that originates waaaaay back in the history of these languages

No, 1-12 are influenced by the old base 12 Germanic/Norse system, which is why -teen starts at thirteen, same as in German (11: elf, 12: zwölf, 13: dreizehn, 14: vierzehn & so on)... The -teen for 1x in english is also a carryover from this, being threeten, fourten, fiveten etc. with only numbers over 20 having their orders reversed - German has something similar with "und" only appearing in numbers over 20. English did historically too, eg. "four and twenty blackbirds".

Base 20 was historically used for large numbers though, eg "four score and seven years" by Abraham Lincoln, which was a poetic way of saying 87 inspired from Psalms 90:10, which says "The days of our years are threescore years and ten; and if by reason of strength they be fourscore years, yet is their strength labour and sorrow; for it is soon cut off, and we fly away." in the King James Version, which reflects that using base 20 for large numbers (and not just 80) was not uncommon in the 17th century.

93= Four score and a baker's dozen.

So do you mean to suggest "quatre-vingt-dix" just means 90 and doesn't also mean "four-twenty-ten"?

As a non-native working in German, the numbers are one of the trickiest parts.

My jobs generally involve a lot of math and discussions of numbers, and I often struggle with swapping numbers around in my head. Especially because when you get to bigger numbers people often switch between (or use a combination of) listing individual digits left-to-right and saying multi-digit numbers.

The though is when you occasionally notice natives mess it up!

Funny thing: it is the correct way to count like that, also in english. Four-teen, eight-teen etc. They just turn that around beginning with twenty. How obscure is that shit, when you really think about it?

The older generation in Norway also uses that format. I usually tell them that we aren't under German occupation anymore, so they should use the sensible format.

Yes! I'm German and I hate it. It's also very inconvenient when entering numbers into a spreadsheet or something, because you have to know the whole number before you can start typing it.

Its so annoying with phone numbers as well, depending how someone pronounces is. My mom always says phone numbers in 2 digits, like 06 12 34 56 78 (06 twelve fourandthirty sixandfifty eightandseventy) and you just get confused because you want to type in the first number pronounced

It just feels weird saying it the other way tho

I love how halvfems exists but fems doesn't (and I guess it never did)

When I'm in Denmark and have to say 92 I just say "kamelåså"

(5-0,5)x20 = 4,5x20 = 90? 2+((5-0,5)x20) = 2+(4,5x20) = 2 + 90 = 92?

How did you guys even get to this thought process for saying this sort of thing? Why would you work in fractions for whole numbers in language to start? Is this a monarch thing like they fancied themselves a math wizard so they said it like it was a solution on countdown and others mimicked to keep them happy/sound smart themselves?