I wrote a (very long) blog post about those viral math problems and am looking for feedback, especially from people who are not convinced that the problem is ambiguous.
It’s about a 30min read so thank you in advance if you really take the time to read it, but I think it’s worth it if you joined such discussions in the past, but I’m probably biased because I wrote it :)
The ÷ sign isn’t used by “Americans”, it’s used by small children. As soon as you learn basic mathematical notation in your introductory algebra class, you’ve outgrown the use of that symbol.
I don’t know where you’re from, but it’s used universally in Australia - textbooks, calculators, all ages - and from what I’ve seen the U.K. too.
Children here in the Netherlands use : as a divisor symbol. I don’t know whether the ÷ sign is particularly American, but it’s not universal.