Poll: Lack of basic mathmatical skills
- Thread starter barbzilla
- Start date
I personally never learnt the PEMDAS system in school at any point and I really dont like the way people write their mathematics to be deliberately confusing. Problems like these are only there to serve the purpose of somone being able to go "Hur hur hur - youre so dumb you cant even do basic maths".DoPo said:
If you do maths and want to make what youre trying to do clear you use brackets to show the exact order.
Hence you get:
1+1+1+1+1+1-1+1+1+1+1+1+1-1+(1x2)
or
(1+1+1+1+1+1-1+1+1+1+1+1+1-1+1)x2
and
2+2+(2*0)
OR
(2+2+2)*0
Its so simple to do that I cant help but think that the ONLY reason these exist is for peoples superiority complexes.
Im currently doing a degree in mathematics and I do modules in quantum physics and advanced electromagnetism. These problems sometimes trip me up not because im a bad mathmetician but because the writing of such problems is DESIGNED to trip you up. If I was writing this as a genuine mathematical problem I would not write it like that.
USE BRACKETS when writing equations. Simples.
48 ÷ 2 * (9+3)= either 2 or 288 depending on whether you multiply or divide first
Multiplication and division hold no precedence over each other as division is simply the inverse function of multiplication (IE divide by two or multiply my .5 yield the same results), like how - 1 and + -1 mean the same thing.
Think of it this way, after the 3rd grade you never use the symbol ÷ again, rather you put what you want divided on top of a line, and what you want it divided by on the bottom of the line, and the line has a dual role as a parenthesis.
order of operations should be thought of more like this
Parenthesis AND Indices
Multiplication AND Division
Addition AND Subtraction
Multiplication and division hold no precedence over each other as division is simply the inverse function of multiplication (IE divide by two or multiply my .5 yield the same results), like how - 1 and + -1 mean the same thing.
Think of it this way, after the 3rd grade you never use the symbol ÷ again, rather you put what you want divided on top of a line, and what you want it divided by on the bottom of the line, and the line has a dual role as a parenthesis.
order of operations should be thought of more like this
Parenthesis AND Indices
Multiplication AND Division
Addition AND Subtraction
I studied TP for my undergrad (at Trinity College, Dublin). Up until then, I had never encountered any maths problem that gave me any trouble whatsoever*. The first year of university level maths kicked my arse from one end of campus to the other. As I understand it, the British A-level maths goes a fair bit beyond the Irish Leaving Cert in scope, but I think that you should be prepared for a whole different level of conceptual abstraction.Redingold said:
It took me a solid 18 months to get to grips with complex analysis and abstract algebra, both of which are hugely important to the mathematical foundations of QM and GR. As far as I know, most physicists are happy to ignore the pure maths formalisms behind the equations, but I found that understanding one led to huge gains in grasping the other.
I'm consistently surprised by how often the weird and abstract maths I learned in TP pops up in other places. I spent a few years training as an actuary, and an understanding of statistical thermodynamics goes a long way to reading modern theories of financial markets. Now I'm about to complete an MSc in computer science (I should be writing my thesis right now) and so much of the same abstract maths underlies both physics and CS.
I'm sure that you'll do great, but I think you should be ready for a new level of difficulty from anything you've encountered before.
* Not strictly true, I tried out for the Mathematical Olympiad, and I'm not convinced that the problems we were posed were even meaningful!
I work in retail so at most I would use math at the till (I'm not fully trained on it just yet) but in saying so, the till give you the cost and total so math thinking is not fully involve other than giving out the right changed.
Other than that I guess I use math for simple thing like working out by head of a total or adding stuff together.
Other than that I guess I use math for simple thing like working out by head of a total or adding stuff together.
I got a B grade at GCSE maths but I could've gone and done A-levels. Chose not to. So middle of the road, mathmatical skills come up every so often but I've probably gotten rusty with higher level stuff
And I have yet to see hat the OP described (mostly because all of my friends have decent maths skills) but from the sounds of it, seeing something like that would kill me a little on the inside. I used to hear phrases like "We don't need maths" from a lot of individuals at my school when we were young and less mature (read:intelligent). Made me want to punch them but I wouldn't
And I have yet to see hat the OP described (mostly because all of my friends have decent maths skills) but from the sounds of it, seeing something like that would kill me a little on the inside. I used to hear phrases like "We don't need maths" from a lot of individuals at my school when we were young and less mature (read:intelligent). Made me want to punch them but I wouldn't
Note that I'm a business-to-business sales representative at the company I work for, keeping around 150 business customers satisfied all days of the year. I don't work at a bank and I would hardly need maths, if I wanted to.
However, being relatively clever in maths (was one of my best classes back in school), it allows me to do stuff pretty fast. This helps me daily, but it's no necessity.
However, being relatively clever in maths (was one of my best classes back in school), it allows me to do stuff pretty fast. This helps me daily, but it's no necessity.
See my earlier post. The order of operations is completely arbitrary.Syzygy23 said:
The explanations offered by Darkmantle and poiumty explain some of the reasons that we use this particular arbitrary evaluation rule (that multiplication is treated as repeated addition so it makes sense to do it earlier). Also, treating division/multiplication and addition/subtraction as inverse operations with the same level of priority makes equation manipulation (like cancelling something from both sides of an equals) far easier (even if it is a slight misconception).
Ultimately, written maths is a language, and a language relies on consistent interpretation to convey meaning. If we don't all use the same set of rules, then a written formula might be interpreted to mean something far different from what the author intended.
Which is the proper way to go about it. If you strictly follow PEMDAS in the example you gave here, you'd get 0.166666, while if you swapped the order, you'd get 1.5Veloxe said:
When it's written like that, you should absolutely go left to right first. Otherwise, you'd have to worry about keeping track of numerators and denominators on top of everything else.
As a maths teacher I was taught this way and I teach it this way...tbh the division and multiplication doesn't make a huge difference in what order it is in.Keoul said:I'm always confused by the order of operations because I was taught BODMAS first.
Brackets
Powers (forgot what the word was but it's exponents)
Division
Multiplication
Addition
Subtraction
So as you can see Division and Multiplication is switched from PEMDAS, makes it kinda confusing sometimes.
The only use for it in my daily life is Teamfortress 2 Warioware mod
OT: so yea, I use maths all the time...but I think that it's cheating for me to say so
neither was I, we actually understood what we were doing though, and we didn't get out aunt Sally involved or whateverthahat said:could be, might be because devisions and multiplications GO AT THE SAME TIMEKeoul said:I'm always confused by the order of operations because I was taught BODMAS first.
Brackets
Powers (forgot what the word was but it's exponents)
Division
Multiplication
Addition
Subtraction
So as you can see Division and Multiplication is switched from PEMDAS, makes it kinda confusing sometimes.
The only use for it in my daily life is Teamfortress 2 Warioware mod
all i know is
( )
^2
/ AND *
+ AND -
never was taught any nice words for em though XD
people who don't get that multiplication and division are the same do not even grasp that 6/3 is the same as 6*(1/3)
the facebook stuff is a combination of people being stupid, people being lemmingsand following what other people say, people just using their phone/calculator for a calculation and using it wrong, or people using their aunt sally for unholy things but not math
well you say "I consider" but that is not how it works on normal notation, when you calculate bigger problem yes, you use scientific notation and dont type your stuff in MSword or whateverpoiumty said:
but you cant start making up your own rules7/1*9 means only 1 thing 7*9
Those things on facebook aren't really difficult maths, they're just designed to be confusing. What bugs me is that there are people on my course who can't add up a couple of two digit numbers and have no concept of how long 3000mm is. I'm studying building surveying, most of it is measuring buildings, drawing up the plan of them, then making a model with CAD. If you can't add up two numbers, you're buggered.
Ahh I'm so jealous of all your smarts, this is the problem with growing older, suddenly all these darn young people have achieved things you'll never achieveRedingold said:
. Well I can take comfort in you ending up getting the same grades as me, despite having way more success in the Olympiads. Also you took physics, which every mathematician knows is just left over maths. I mean the stuff you do actually has relevance to the universe, doesn't sound very proper to me ------------------
OT I'm a 3rd year mathematician student, so I hope my skills don't completely suck, but I have no intention of using them in any practical way unless it's to get a job doing even more proper maths. Once you have the knowledge, just reapplying it again and again is boring, I can't stand applied modules (except for statistics where intelligence is still required, being more about the interpretation), the fun is constantly gaining new knowledge.
Luckily the purpose of any civilised society is clearly to support mathematicians and to let them do their cool pure stuff that divines patterns in the very fundamentals of existence in comfort, so I'm okay =D
As a former Math and Physics student and current Computer Science student I weep every time I see a person get one of this wrong, thus "Super important"
Still, as a computer science student you are taught to make the operation as simple as humanely possible by using 'redundant' parenthesis because you never know how a compiler is going to behave and every single respectable compiler does at least respect parenthesis first so:
1+5*5-7/1*9
becomes:
(1+(5*5)-(7/(1*9))
This way no one can really get it wrong without being really really stupid, and a compiler won't really ever get it wrong.
Still, as a computer science student you are taught to make the operation as simple as humanely possible by using 'redundant' parenthesis because you never know how a compiler is going to behave and every single respectable compiler does at least respect parenthesis first so:
1+5*5-7/1*9
becomes:
(1+(5*5)-(7/(1*9))
This way no one can really get it wrong without being really really stupid, and a compiler won't really ever get it wrong.
I don't think "arbitrary" is the right word to use. It's not random, and it's not on a whim. There is a definite logical system.tensorproduct said:
"" ar·bi·trar·y -Based on random choice or personal whim, rather than any reason or system.""