Is BODMAS a recent thing ie last 40 years or so .. or has it always been around?

[loveyouradvice]

I don't remember learning it at schools - and I remember using FAR more brackets all over the place which guided order of actions....

My mother is nearly 80 and learned it in her school overseas, which followed the British curriculum of the time.

I’m useless at maths but (dyslexic) and went to dyslexia summer school in England (Scottish) when I was a kid - now 46 and remember being taught it there but not at school - school pretty much wrote me off tbh but I learned lots of hints and tricks which helped me pass my maths exam, I was hopeless, but I think a lot of it was confidence. I was so shy and school were so awful to me I just didn’t believe in myself.
anyway def used it years ago sorry kinda went off on one there 😁 loved those summer schools I felt ‘normal’ and was treated like I could do anything

I’m 51 and was never taught it (and I have a maths degree).

I still think it’s much clearer just to use brackets 🤷‍♀️

E.g. If someone writes 2+2x2, I know it’s 6, but I have to think about it, and I always think it’s sloppy, lazy presentation.

Whereas if you write 2+(2x2) then it’s immediately obvious without having to remember or think about some mnemonic. Especially in more complex equations.

I remember "Boys Of Manchester Drink And Smoke" but I think it came from my parents rather than school!

My dad was from manchester....

Agreed. But later on you are more likely to be using x,y rather than numbers. At which point xy+x is pretty clear and obvious and doesnt need brackets.

I learned it at school and I am older than time.

I’m in my 40s, did maths at school up to an A at further maths and never once heard of BODMAS/PEMDAS! We learned algebra from the ground up and I think the order of operations was implicit in that in any case. Was taught to go left to right, but yes there was more use of brackets: you did the order of operations by multiplying out the brackets first, then going left to right.

I would have said 25. Unless it was written 2+(3x5). But I think BODMAS would make it 17?

The weird thing is - calculators don't do BODMAS. A calculator would make it 25 too as it tots up as it goes along.

I need brackets around the 3x5 but BODMAS doesn't need them.

Am I wrong anyway with both answers?

Yes BODMAS would make it 17.

A good calculator will make it 17.

The idea of BODMAS is we have a universal understanding and don’t need brackets.

OK, you don’t need brackets for something like xy+x, but if someone wrote a+bxc+d, how would you know at first glance whether they meant (a+b)x(c+d) or a+(bxc)+d. Or whether they themselves had applied BODMAS correctly in their head when writing it down!

IMO it’s still far easier just to use brackets. It just does away with any ambiguity.

I will probably always look at something like 2+2x2 written down and wonder why people haven’t been taught to present things properly.

Bring back the bracket!

My calculator (Samsung phone) does BODMAS.

My grandad learnt it at school - I remember him talking to us about how they'd had a particular lesson on it. I don't know how old but it was before he did the 11+. That would have been latest 1927.

In algebra you’d never use x in those situations anyway: you’d write a + bc + d; or even a + b.c + d — with the dot meaning multiplication.

This is because once you start using any algebra, the convention is not to use x as a multiplication symbol, so that it isn’t confused with x as the algebraic symbol. Using the conventions of bc or b.c and of brackets always means you simplify first before you go left to right: if you always simplify your equation before you solve it, you’re implicitly doing the order of operations anyway.

So you don’t ever need to know a rule to solve a + b x c + d, because it never gets written like that in the first place.

I was doing my secondary school maths in the late 80s and early 90s. As far as I recall, we moved on to algebraic conventions pretty quickly in Y7. By Y8 everything we did had a foundation in algebra. So we never saw any notation from that point on that was confusing enough to need a mnemonic or a rule, because we didn’t see x used to mean multiplication. If you are used to seeing an equation as, eg:

4(x + y)

and, using basic algebra, you have been taught that this doesn’t mean:

4 times (x + y)

— but actually means that 4 is a coefficient for the bracket, so it’s a simplification of 4x + 4y, then you don’t get confused and think that it could equally well be (4 x x) + y instead (which is what a lot of Americans on Facebook BIDMAS problems seem to think.)

And just to add to my post above — you do get those Facebook problems that go around occasionally, in which the answer expressed algebraically is different to the answer produced by BODMAS. In those cases it’s a genuine notational problem, in that if you have been taught proper algebra you will genuinely come out with a different answer to someone who is using BODMAS. People can disagree in the comments on those posts for days! But they are genuine conundrums caused by unclear use of notational convention.

BODMAS or whatever one calls it is a set of conventions. So is algebraic notation. However, I’d probably want to argue that the answer as expressed using algebra is a higher or more fundamental order of mathematical reasoning, one that extends throughout calculus and geometry as well, so that if you understand how these facets of mathematics all fit together then you are more likely to rely on algebraic conventions rather than an arbitrary mnemonic for the order of operations. But one is not more “right” than the other: it all depends on the context you’re solving a problem in, and how you’ve been taught to do it.

I just use the calculator online on my laptop.

I just don't understand why brackets have been ditched.

(2+3) x 5 and 2+ (3x5) are clearly different sums. But 2+3x5 is ambiguous.

Well, you can’t do any form of algebra, calculus or advanced trig without brackets. Why the need to ditch them for basic maths and arithmetic? You’d have to reintroduce them at high school level maths anyway.

I agree brackets in the above case make things clearer.

However too many brackets can get confusing.

7(a"3)(3(y"2)+5(z"2))
is harder to understand than without the unnecessary ones.

Edit, especially when mn removes all the power signs, now replaced with "

They havnt - the "B" in bidmas IS brackets!