Quote Originally Posted by Lukie View Post
Also, something else not really relevant to the debate that Rilla and I were having:

I think most of us learned the order of operations as something like PEMDAS or something equivalent (B instead of P and/or O instead of E) but I wonder why that specific acronyn is taught with M before D, and here's why (not 100% sure on this theory but as I was throwing some numbers around it appears to be true):

As the multiplication/division level, I'd argue that putting division first is a superior way to teach it. If the left-to-right rule is observed, it doesn't matter, but if it's forgotten then I *THINK* doing division before multiplication will always yield the correct answer, but doing multiplication before division may not (again, this is a moot point if done left-to-right, but that is an added and perhaps unneeded specific instruction to teach students)

10*5/2

left-to-right method = 25
division first method = 25
multiplication first method = 25

15/5*3

left-to-right method = 9
division first method = 9
multiplication first method = 1
Unless you're multiplying or dividing by 0.5, then you're fucked.