Ah, I wasn’t thinking of calculators that let you type in a full expression. When I was in school, only fancy graphing calculators had that feature. A typical scientific calculator didn’t have juxtaposition, so you’d have to enter 6÷2(1+2) as 6÷2×(1+2), and you’d get 9 as the answer because ÷ and × have equal precedence and just go left to right.
https://plus.maths.org/content/pemdas-paradox
Even two casios won’t give you the same answer:
https://plus.maths.org/content/sites/plus.maths.org/files/articles/2019/pemdas/calculators.png
Ah, I wasn’t thinking of calculators that let you type in a full expression. When I was in school, only fancy graphing calculators had that feature. A typical scientific calculator didn’t have juxtaposition, so you’d have to enter 6÷2(1+2) as 6÷2×(1+2), and you’d get 9 as the answer because ÷ and × have equal precedence and just go left to right.