Chances are unless it's a very small class or there are extenuating circumstances, professors normally don't round up unless they've stated it. Usually changes made for one student are applied to the whole case to be fair. There may be exceptions but the rule is generally a 89.9 stays an 89.9

Originally Posted by rcmp1234

hmm, for one of my classes, my final mark ended up being 89.9 (lol), and I got a 11. I'm planning on emailing the prof, but should that technically be a 12?

That's so close to a 12!! If i were you i would email the prof, maybe s/he will push you up. Look over your assignments/midterms/labs and ask your prof to remark something.
Hopefully you get a 12

Originally Posted by Mac-10

Your mark will be an A-, which means 80 percent. So the other 4.2% is pretty irrelevant.

Where did you get that impression? A 10 or A- is 80-84. An 80 is roughly a 9.5 (this is what is used for determining the Deans' Honour List.