It is also frustrating when different calculators have different orders of operations and dont tell you.
Yeah, but to be fair most of them do tell you the order of operations they use, they just bury it in a million lines of text about it. If they could all just check with some Maths teachers/textbooks first then it wouldn't be necessary. Instead we're left trying to work out which ones are right and which ones aren't. Any calculator that gives you an option to switch on/off "implicit multiplication", then just run as fast as you can the other way! :-)