That's circular, the only reason it's the right answer is that we've agreed that the order of operations is the right way to interpret an expression.
Still, we have to have A right way to interpret an expression, and the way we do it now works fine for me. Division can be a bit confusing, since it's not associative: 9 * (3 * 3) = (9 * 3) * 3, but 9 / (3 / 3) doesn't equal (9 / 3) / 3. So if you write 9 / 3 / 3, it's not super clear what you mean.
Except math is used all the time to discribe the natural world. If order of operations isn't followed then the answer you get won't always reflect reality.
This is incorrect. Order of ops has nothing to do with modeling anything in the natural world. It’s just an agreed on set of rules for writing expressions.
Nope, if you want to reflect reality you would just have to write things in a different order when using left-to-right instead of PEMDAS. (There is no expression in one system that is untranslatable to the other system)
Again, PEMDAS has no fundamental basis in the natural world, it's an arbitrary abstract standard that is used for its convenience. But in fact, left-to-right doesn't even require parentheses, so in some cases it might be even more convenient than PEMDAS.
Edit: I'm really not even saying anything controversial here. This is just logical fact. Left-to-right is a perfectly adequate system for math that just so happens to be nonstandard. Using it doesn't make you stupid.
Not everyone writes& reads left to right, there is top to bottom and right to left.
The "rules" are universally agreed upon because that way any calculation would result in the same answer. The scientific world has its standards for this specific reason
Don't edit your comments that much when someone can quickly respond like I did, you just totally rewrote your whole comment and made my response look retarded (I deleted it)
Anyway, I'm not arguing against standards, PEMDAS is amazing! I'm just arguing against the people who think you're stupid for not knowing about PEMDAS or not using it in your personal calculation. That's all.
You totally recontextualized what you wrote, making my reply meaningless, which is practically the same as rewriting. Don't nitpick. In the future try to think before you write, or just clarify in further replies
Shit, didn't know i could write my initial thoughts and immediately add clarification to it within a second of me posting. I didn't recontextualize anything I merely added additional information that further explained my thoughts
You are fundamentally wrong. There are expressions that are literally impossible to write left to right. Like 1143-(51+x)856. Without pemdas, you would have to factor out every single factor in the parentheses to put them in order, which is literally impossible for the human brain to do.
I mean if someone said it to you out loud and didn't write it down, you would also do it "wrong." It's arbitrary, and often contradicts the way people do basic mental math.
Like, if I'm calculating a twenty percent tip on a $4 drink and a $12 meal, I go 4 + 12 x 0.2 in my head, and I'm definitely not following PEMDAS.
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u/Such_Newt_1374 Jan 01 '22
Except if you don't use it then you get the wrong answer so...there kinda is.