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This is a link post 10 + 10 X 0 = 10?
I am completely confused by this, I was taught Maths reads from left to right same as writing, the way I see it, you have 10 objects, you then add 10 objects, so you got 20, the multiplication tagged into the end makes no difference to anything because nothing is nothing so does nothing, you still have 20 objects*, it would only be 10 if it was done right to left (nothing times 10 equals nothing, plus 10) which almost everyone in the comments agrees is the correct way to do it.

WTF!?

Is this some major difference in math Merkin style or something, like the way they do dates, or is this some way of doing math where you perceive it as a formulae with entirely different rules rather than anything applicable to physical objects, read in the order written?

Discuss...

*edit* oopsie I forgot multiplication by zero is always zero regardless, confused by trying to think of it as physical objects, ignore that bit ;)

*edit edit* as my argument is invalid here's an appropriate picture:

 (I helped save b3ta! ..wil, Sun 5 Jun 2011, 10:51, Reply)
This is a normal post it's to do with order of operations
BIDMAS (Brackets, indices, division, multiplication, addition, subtraction).

If you calculate it following that order you get 10.
10 x 0 = 0
0 + 10 = 10

www.bbc.co.uk/schools/ks3bitesize/maths/number/order_operation/revise2.shtml
 (I helped save b3ta! nivoser tangos with the devil, Sun 5 Jun 2011, 10:55, Reply)
This is a normal post I was...
...absolutely amazed that WiL wasn't taught this in school.

And then I saw the replies about BIDMAS and realized I was taught something different in school... MDAS (My Dear Aunt Sally) for the order * / + -

Wheird.
 (theSHALROTH Gaga's tits are on fucking fire!!!, Sun 5 Jun 2011, 11:11, Reply)
This is a normal post must be different all over the place
and depending on when you learnt it, I guess.
 (I helped save b3ta! nivoser tangos with the devil, Sun 5 Jun 2011, 11:29, Reply)
This is a normal post BIDMAS for me, too.
MDAS is fine, but it doesn't tell you about brackets or indeces.
 (I helped save b3ta! Enzyme is powered by sunlight, Sun 5 Jun 2011, 12:16, Reply)
This is a normal post I was taught at school
the BODMAS rule, which is the order in which you would do the maths. BODMAS is brackets, or division, multipication, addition and subtraction, so in this case it would be 10 x 0 = 0; 0 + 10 = 10. Its been a fair few years since I've done this so I'm probably wrong...

EDIT: Turns out I was right!
 (ProfessorNoShoes wishes he was better at Photoshop, Sun 5 Jun 2011, 10:57, Reply)
This is a normal post I was taught the "O" in BODMAS was "order"
By which they meant exponentiation.
 (Pie of Meat ___°¬¯O¯____\o/_____/\_,____Y¯¯Y, Sun 5 Jun 2011, 11:39, Reply)
This is a normal post BIDMAS:
Brackets, indeces, division, multiplication, addition, subtraction. (A bit like PoM in the previous reply.)
 (I helped save b3ta! Enzyme is powered by sunlight, Sun 5 Jun 2011, 12:17, Reply)
This is a normal post Priority of operatons
This isn't a left-right thing, it's priority of operations. Multiplies are higher priority so you do them first. This lets you write equations like a = 10b + 5c without tons of brackets (brackets say that a part of a formula has to be done first). With brackets the above is 10 + (10 * 0) = 10.
 (funkatron, Sun 5 Jun 2011, 11:00, Reply)
This is a normal post I have NEVER been taught this and I've programmed computers too, and it all worked fine and as expected,
as has it in the physical world, I understand that when brackets are used that means that that part of the equation must be done first, BUT I was never taught that when maths is written in a sentence like that that it is not to be read as a series of instructions, but as a 'math language' which has rules of order of execution regardless of lack of brackets.

This is weird, how can I not have known this till forty fucking three!?

My school teachers must have been shite!
 (I helped save b3ta! ..wil, Sun 5 Jun 2011, 11:11, Reply)
This is a normal post chances are the compiler for your programming language will have taken care of precedence for you?
It's odd for a maths teacher to forgot to teach this...
 (I helped save b3ta! Mousing, Sun 5 Jun 2011, 11:19, Reply)
This is a normal post Compiler, Hah!
I believe it was Sinclair 8K BASIC.
 (theSHALROTH Gaga's tits are on fucking fire!!!, Sun 5 Jun 2011, 11:20, Reply)
This is a normal post It was 1k basic
and you should know better, there was that or a 16k expansion pack! ;)
 (I helped save b3ta! ..wil, Sun 5 Jun 2011, 11:21, Reply)
This is a normal post I can't believe you just tried to correct me on a retro issue.
I'm still right. The Sinclair BASIC language / OS was on an 8K ROM in the ZX81 (4K in the ZX80). Only the RAM size was 1K.
 (theSHALROTH Gaga's tits are on fucking fire!!!, Sun 5 Jun 2011, 11:28, Reply)
This is a normal post Oh stop it!
I'm still reeling from the sudden knowledge there's a language to math I never knew about till now!
 (I helped save b3ta! ..wil, Sun 5 Jun 2011, 11:29, Reply)
This is a normal post you guys are old :p

(I helped save b3ta! Mousing, Sun 5 Jun 2011, 11:30, Reply)
This is a normal post Thanks.
I'm thirty-one.
 (theSHALROTH Gaga's tits are on fucking fire!!!, Sun 5 Jun 2011, 11:31, Reply)
This is a normal post Coffin dodger!
*blows raspberry at the old man*
 (I helped save b3ta! ..wil, Sun 5 Jun 2011, 11:34, Reply)
This is a normal post not much older than me then :)
/stands corrected
 (I helped save b3ta! Mousing, Sun 5 Jun 2011, 11:34, Reply)
This is a normal post oh dear oh dear
you weren't very good a programming then I gather?
 (I helped save b3ta! Firkinfedup last shat on your wife's tits at, Sun 5 Jun 2011, 14:22, Reply)
This is a normal post No discussion needed
Discuss? No need. Multiplying has a higher priority than adding.
 (jaredearle There is no spork., Sun 5 Jun 2011, 11:10, Reply)
This is a normal post Yeh I figured by asking the question I was gonna get a load of 'DHURR! YOU STUPEEED!' answers
but if you look at the comments above you can see a lot of people are equally confused and I wondered if there was a disparity of rules taught in different areas, as it's not something I recall ever having been taught and is entirely new to me, which cracks my head a little!

I can't help but wonder tho, as I'm now seeing it with fresh eyes, if the order it's written in is not the order in which it should be performed, then why not write it in the order it will?
 (I helped save b3ta! ..wil, Sun 5 Jun 2011, 11:18, Reply)
This is a normal post It shouldn't matter which order it's written in...
...because it's always worked out in the correct order (usually).
 (theSHALROTH Gaga's tits are on fucking fire!!!, Sun 5 Jun 2011, 11:34, Reply)
This is a normal post IF someone remembered to tell you math HAS an order!

(I helped save b3ta! ..wil, Sun 5 Jun 2011, 11:41, Reply)
This is a normal post I learned that if you need certian parts worked out first they should be in brackets
so I would have come up with 20. but if I put 10 + 10 x 0 in to a scientific calculator I get 10 but if I put it in to a normal calculator I get 0. Odd.
 (I helped save b3ta! Peej, Sun 5 Jun 2011, 11:13, Reply)
This is a normal post Yeh...
...pocket calculators don't evaluate the entire expression when you press 'equals,' it performs that operation to the result of the previous operations, so 1 + 2 * 3 will be evaluated as (1 + 2) * 3, when you should think of it as 1 + (2 * 3).
 (theSHALROTH Gaga's tits are on fucking fire!!!, Sun 5 Jun 2011, 11:20, Reply)
This is a normal post Yeh if I ask Google as a whole maths problem it says 10
but if I type it into a simple handheld calculator it says 20, presumably tho 'cos I'm not changing the order.

Confusing!
 (I helped save b3ta! ..wil, Sun 5 Jun 2011, 11:20, Reply)
This is a normal post It should say 0...
...because the final operation is multiply by 0, which is always, you guessed, 0.
 (theSHALROTH Gaga's tits are on fucking fire!!!, Sun 5 Jun 2011, 11:30, Reply)
This is a normal post Oh yeh correct,
sorry I got that wrong!

Jeez it's a LONG time since i had to do math in my head, curse of the modern world I guess!

*edit* Which means I wrote my OP wrong too, DUH! I think I regressed to my 8 yo self when we were taught to do basic maths problems with pennies, I forgot a multiplication by zero is zero rather than thinking of it as unchanged physical objects, same as a division by zero is INFINITY AND BEYOND!!
 (I helped save b3ta! ..wil, Sun 5 Jun 2011, 11:35, Reply)
This is a normal post Maths
or sums. not math. that's spanish.
 (poocheim No al calcio moderno, Sun 5 Jun 2011, 12:02, Reply)
This is a normal post I tend to say a math problem, or doing math,
and maths as the subject.

I think there's a difference in American English and English English to that end and as ever when that happens the two end up being sort of mashed together.
 (I helped save b3ta! ..wil, Sun 5 Jun 2011, 12:06, Reply)
This is a normal post only slaggin

(poocheim No al calcio moderno, Sun 5 Jun 2011, 12:14, Reply)
This is a normal post Strange
I was only taught that brackets came first, I thought the answer was 0 too.
I did higher level Maths in secondary school, but this is the first I heard of any BIDMAS/PODMAS rule.
 (cH3$h7846J#7, Sun 5 Jun 2011, 11:29, Reply)
This is a normal post Well I'm glad I'm not the only one with the balls to admit they never knew about it
out of curiousity what age are you as I'm wondering if this was simply accidentally missed off of the teachers text books back in the day (I'm 43).
 (I helped save b3ta! ..wil, Sun 5 Jun 2011, 11:32, Reply)
This is a normal post I'm glad you mentioned it...
...we've got a fairly lively discussion going and a whole lot of knowledgable people all saying they've been taught different things at school...

(edit)

I started doing Maths at 'A'-level and I remember being taught Multiplication came before Division (as has also been mentioned here).

I guess, within a given group of people (say, a regional area) if everyone uses the same notation, it doesn't matter as everyone will get the same answer. It's when you go wider that you get problems...
 (theSHALROTH Gaga's tits are on fucking fire!!!, Sun 5 Jun 2011, 11:39, Reply)
This is a normal post What freeks me about this tho is my concept of the application of math is apparently entirely wrong and has been all my life
yet my application of it day to day has always produced the answers *I* perceive as correct and it's always done what I expected it to.

That's really rather odd, you would have thought at some point I'd have had something throw up an anomaly that made me think 'WTF!?' and question what I was doing wrong, esp when using ye olde computers that had to be programmed...
 (I helped save b3ta! ..wil, Sun 5 Jun 2011, 11:46, Reply)
This is a normal post You don't need to be good at maths to program computers.

(I helped save b3ta! JamTallons, Sun 5 Jun 2011, 17:57, Reply)
This is a normal post Hahaha!
Yeh ya just used the Dragon 32's preloaded games engine that emulated 3 dimensional physics for you, eh?
 (I helped save b3ta! ..wil, Sun 5 Jun 2011, 20:58, Reply)
This is a normal post Dragon 32!? Ha ha ha!
I had a proper computer - 64 all the way. :-).
 (I helped save b3ta! JamTallons, Mon 6 Jun 2011, 21:53, Reply)
This is a normal post
I'm 24, so I don't think it has to do with when we were in school.
I'm also Irish so maybe our curriculum hasn't caught up yet?
 (cH3$h7846J#7, Sun 5 Jun 2011, 13:10, Reply)
This is a normal post It's the BODMAS thing.
Seems silly, but try solving more complex equations without using it. You can't.

I can't remember being taught it at school either. I came across it in 'Advanced Homework for Adults' last year.
 (I helped save b3ta! The Awful Puppy Bakery is still bored, Sun 5 Jun 2011, 11:45, Reply)
This is a normal post I've been looking up that BODMAS acronym since I started this discussion
and altho some folks seem confused as to what the O is I know and knew ALL parts the acronym stands for, I simply was never told there was a set order of execution if no brackets or exponents were present.

God my mind is literally blown that I've got THIS far in life without knowing that, weird!

*goes to lie down*
 (I helped save b3ta! ..wil, Sun 5 Jun 2011, 12:03, Reply)
This is a normal post I was taught it when I was 11.
I'd met brackets by that point, but the notion of powers was utterly alien at that stage.
 (I helped save b3ta! Enzyme is powered by sunlight, Sun 5 Jun 2011, 12:19, Reply)
This is a normal post Try going to a welsh school mate.
now that will mess your maths up.
:(
 (I helped save b3ta! --- ---, Sun 5 Jun 2011, 12:19, Reply)
This is a normal post
1 not come ha1r 2 lern l0lz
 (I helped save b3ta! enoughblueskyforsailorstrousers, Sun 5 Jun 2011, 12:24, Reply)
This is a normal post I never got my head around 'a minus x a minus = a possitive'
If I don't have 3 oranges and multiply that by not having 2 oranges I now somehow have 5 oranges!!! Think I got caned at school for "arguing" with the teacher about that one. Load of old bollocks maths
 (I helped save b3ta! acab, Sun 5 Jun 2011, 15:28, Reply)
This is a normal post I think you mean
6 oranges :P
 (Buftoon posted this on, Sun 5 Jun 2011, 19:06, Reply)
This is a normal post Maffs baint my best subject!!

(I helped save b3ta! acab, Sun 5 Jun 2011, 19:20, Reply)
This is a normal post I think I was taught this at pretty much every level of my education..
So I've known this since the first time multiplication and division came up in first or second grade. And it was STILL mentioned when we took our first courses in programming, because things like this exist: www.cs.uwf.edu/~eelsheik/cop2253/resources/op_precedence.html

I remember being shown some ridiculous, long strings of +, -, = signs and bracets with two or three variables within, each appearing a few times; and then being assigned the task of puzzling out the end values of all those variables. Mostly it was to give us an example of how NOT to program and encourage us to strive towards producing readable code, of course. It certainly is possible to handle precedence correctly with just a generous use of brackets, even if you ignore all the other rules, and often that can be the easiest to read also.

Anyway, my mind is blown that not all people know about this.. Either teaching has gone up a long way in ~20 years, or I have just been lucky with my maths education :)
 (Roxon, Mon 6 Jun 2011, 21:37, Reply)