I entirely agree, when I was at school the order of operation was avoided as much as possible, i.e. it was not drummed into students and was avoided with the use of brackets, of course the order of exponents had to be made clear to avoid things like 3x(b^2) and instead have 3b^2. As you rightly say, ambiguity is the problem, and this adds an extra confusion to people learning mathematics that they could do without.
40+40x0+1 =
- Thread starter kokuten
- Start date
I entirely agree, when I was at school the order of operation was avoided as much as possible, i.e. it was not drummed into students and was avoided with the use of brackets, of course the order of exponents had to be made clear to avoid things like 3x(b^2) and instead have 3b^2. As you rightly say, ambiguity is the problem, and this adds an extra confusion to people learning mathematics that they could do without.
![[FnG]magnolia](/styles/overclockers/avatars/9.png){kind=avatar}
Caporegime
- Joined
- 29 Aug 2007
- Posts
- 28,860
- Location
- Auckland
Bodmans? Do you want a flake in that, love?
Man of Honour
- Joined
- 27 Sep 2004
- Posts
- 25,821
- Location
- Glasgow
[FnG]magnolia;20547574 said:
Melanie Sykes says "so close and yet so far away...".
But I appreciated the reference anyway.I was never taught any acronym like BODMAS but was certainly taught the order of operations.
You have to be careful with BODMAS, the precedence order is :
Brackets,
Orders (i.e powers)
Divide AND Multiple, with precedence taken from left to right
Add AND Subtract, with precedence taken from left to right
i.e., Divide does not have a precedence over multiple, same for add and subtract. The convention is to read the equation left to right in this case.
For the people that don't get it, how would you work out something like 5x + 10y - 4z, if you don't take the multiplications as highest priority then it makes no sense.
You have to be careful with BODMAS, the precedence order is :
Brackets,
Orders (i.e powers)
Divide AND Multiple, with precedence taken from left to right
Add AND Subtract, with precedence taken from left to right
i.e., Divide does not have a precedence over multiple, same for add and subtract. The convention is to read the equation left to right in this case.
For the people that don't get it, how would you work out something like 5x + 10y - 4z, if you don't take the multiplications as highest priority then it makes no sense.
Caporegime
- Joined
- 29 Aug 2007
- Posts
- 28,860
- Location
- Auckland
e : silly posting by me, apologies.
Last edited:
Man of Honour
- Joined
- 29 Mar 2003
- Posts
- 58,014
- Location
- Blurton
But you don't disagree that the answer is 41?
It's 41, but I fully appreciate why people would get the wrong answer when the question is deliberately poorly written.
Thank you.
Took me a good five minutes to get my head around this line, 2 x 3 + 2 x 4 = 6 + 2 x 4 = 8 x 4 = 32 in context.
I was like
I don't have a good capacity for maths.
Man of Honour
- Joined
- 17 Feb 2003
- Posts
- 29,640
- Location
- Chelmsford
[TW]Sponge;20541923 said:
Banks when they calculate the interest you owe them.. Or if you're lucky, how much they owe you.. So programmers may translate such an equation into a program so you don't have to worry about this kind of thing. So really you're kind of right... And this is it in a nutshell really, unless there's a specific need or interest then there is no need for the knowledge as there are tools that do it for us.
For example, if I were calculating interesting then the equation would look like this:
Let's say you borrowed £5000 at a rate of 5% for 200 days
Amount x rate / basis x number of days
Translates to
(Amount x (rate / basis)) x number of days
So you would do the divide first and so forth
(5000 x (.0500/365)) x 200 = 136.99
It would be a completely different answer if done from left to right..
(hopes i'm right )
Banks when they calculate the interest you owe them.. Or if you're lucky, how much they owe you.. So programmers may translate such an equation into a program so you don't have to worry about this kind of thing. So really you're kind of right... And this is it in a nutshell really, unless there's a specific need or interest then there is no need for the knowledge as there are tools that do it for us.
For example, if I were calculating interesting then the equation would look like this:
Let's say you borrowed £5000 at a rate of 5% for 200 days
Amount x rate / basis x number of days
Translates to
(Amount x (rate / basis)) x number of days
So you would do the divide first and so forth
(5000 x (.0500/365)) x 200 = 136.99
It would be a completely different answer if done from left to right..
(hopes i'm right )
Man of Honour
- Joined
- 17 Feb 2003
- Posts
- 29,640
- Location
- Chelmsford
Basically, calculate one days interest based on a 365 day year (the basis) times the number of days interest 
Soldato
- Joined
- 5 Jul 2003
- Posts
- 2,864
- Location
- Cheshire
Out of curiosity I gave the sum to my two kids last night, 8 year old and 12 year old, both came back with 41 (the 12 year old glanced at it an answered, smart ass ).
I learnt this at school (late 70's early 80's), although it wasn't called BODMAS (you can't really move beyond basic 2+2 without learning it).
I can understand how most people would forget if they don't use it day to day though.
I don't think the lack of brackets is lazy, the sum is written correctly with or without. I'd only use brackets where absolutely necessary.
).I learnt this at school (late 70's early 80's), although it wasn't called BODMAS (you can't really move beyond basic 2+2 without learning it).
I can understand how most people would forget if they don't use it day to day though.
I don't think the lack of brackets is lazy, the sum is written correctly with or without. I'd only use brackets where absolutely necessary.
Nah convention is necessary even with a well written expression otherwise you'd get a very messy expression.
yeah and it had brackets
To be honest I'd probably just keep using brackets until it was clear.
Black and blue, no brown and blue, pass....
