Yeah, this problem comes up with 50, 60, 70, 80 and 90 in Danish, because those are counted in "number of twenties" for some reason. And not like "3-and-a-half-twenties" but rather "halfway-towards-the-fourth-twenty". That example is 70 by the way (halfjersindstyvende). And nowadays it's shortened to omit the "twenties"-part. So in this case just "halvfjers".
The naming convention is pretty whack, but it's just treated as irregular naming in normal use. The alternative, would be to rename those numbers to femti, seksti, syvti, otteti, and niti, but that's very much an uphill battle against habit. So for now. 50, 60, 70, 80, and 90 just have unique names...
For people asking why France is split, they used Occitan for the southern part, which I think is an interesting choice to show the regional language even if most people don't speak it.
Not ideal, though. A mixed area would have been better.
Acknowledging Occitan is important but it gives the false impression that a majority speaks it. And it goes way too north.
So, are we (Czechia) the only ones who use more than one way?
90+9 (ninety-nine literally) is the formal way to do it, while 9+90 (nine-and-ninety literally) is the informal way. You can easily hear both of the ways used in one sentence.
Norway as well. 90+9 is the official way, 9+90 is the way from when the Germans occupied the country. Both are still used. The map also says Georgia and Finland also use two variations.