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On April 09 2011 05:18 chonkyfire wrote:Show nested quote +On April 09 2011 05:13 Sluggy wrote:On April 09 2011 05:02 Roggay wrote:On April 09 2011 04:58 Sluggy wrote:On April 09 2011 04:52 Roggay wrote:On April 09 2011 04:48 Sluggy wrote:On April 09 2011 04:37 Shadowcloak wrote:
why does it ask math at university lvl this is high school material order of operations is elementary school material. The interest of the poll is how people studying math at a high level can overlook the standard way of evaluating expressions. It doesn't say anything about the ability of these people to understand elementary school concepts, but it does serve as a reminder that there are ambiguities in the way things can be evaluated and that is why standardized conventions exist in the first place. The standard convention requires parenthesis for such cases, atleast its what they taught me at school here, and its more logic this way. Here standard convention means the accepted way of handling things. The standard at your school could be to parenthesize everything so that no ambiguities can exist, but in general you don't need parenthesis to evaluate it if you follow a convention. The standard convention says division and multiplication have the same precedence so how do you choose? The standard is to then evaluate expressions from left to right if the precedence is the same. Ambiguity is eliminated after that. I could state my own convention that once precedence is established to evaluate from right to left, but it wouldn't be standard. It is maybe a standard in the US, but it may not in other places. The standard in my country is to put parenthesis to exclude any ambiguity, anything else is false. Is that really the standard in your country? I don't care about trying to say whose standard is more correct, because that doesn't make sense. However, I am interested in any nation's math representative (lol) declaring official conventions for a country. I'm a programmer so I just parenthesize everything anyway just in case whatever compiler I'm using has a different convention for some ungodly reason. ![[image loading]](http://i.imgur.com/aP7Gg.jpg)
Horray! I was felling bad because I'm still thinking the answer is 2... the worst part of this is that I teach at college...
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48
_________ = what's the answer?
2(9+3)
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On April 09 2011 05:25 chonkyfire wrote:
48
_________ = what's the answer?
2(9+3)
This would be 2, and for
48
--- (9 + 3)
2
it is 288.
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On April 09 2011 05:23 MasterOfChaos wrote:At least one reputable source, namely the American Mathematical Society used high priority for omitted multiplication signs in their publications. Show nested quote +We linearize simple formulas, using the rule that multiplication indicated by juxtaposition is carried out before division. For example, your TeX-coded display $${1\over{2\pi i}}\int_\Gamma {f(t)\over (t-z)}dt$$ ![[image loading]](http://latex.codecogs.com/gif.latex?$${1%5Cover{2%5Cpi%20i}}%5Cint_%5CGamma%20{f(t)%5Cover%20(t-z)}dt$$) is likely to be converted to $(1/2\pi i)\int_\Gamma f(t)(t-z)^{-1}dt$ ![[image loading]](http://latex.codecogs.com/gif.latex?$(1/2%5Cpi%20i)%5Cint_%5CGamma%20f(t)(t-z)^{-1}dt$) in our production process. http://replay.waybackmachine.org/20011201061315/http://www.ams.org/authors/guide-reviewers.html
word, that is just saying their convention for a / bcd = a / (b*c*d) when the numerator and denominator are being displayed with a vertical separation rather than inline
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On April 09 2011 05:29 Ropid wrote:Show nested quote +On April 09 2011 05:25 chonkyfire wrote:
48
_________ = what's the answer?
2(9+3) This would be 2, and for 48 --- (9 + 3) 2 it is 288.
yeah so you'd need brackets around (48/2)
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On April 09 2011 05:13 Sluggy wrote:Show nested quote +On April 09 2011 05:02 Roggay wrote:On April 09 2011 04:58 Sluggy wrote:On April 09 2011 04:52 Roggay wrote:On April 09 2011 04:48 Sluggy wrote:On April 09 2011 04:37 Shadowcloak wrote:
why does it ask math at university lvl this is high school material order of operations is elementary school material. The interest of the poll is how people studying math at a high level can overlook the standard way of evaluating expressions. It doesn't say anything about the ability of these people to understand elementary school concepts, but it does serve as a reminder that there are ambiguities in the way things can be evaluated and that is why standardized conventions exist in the first place. The standard convention requires parenthesis for such cases, atleast its what they taught me at school here, and its more logic this way. Here standard convention means the accepted way of handling things. The standard at your school could be to parenthesize everything so that no ambiguities can exist, but in general you don't need parenthesis to evaluate it if you follow a convention. The standard convention says division and multiplication have the same precedence so how do you choose? The standard is to then evaluate expressions from left to right if the precedence is the same. Ambiguity is eliminated after that. I could state my own convention that once precedence is established to evaluate from right to left, but it wouldn't be standard. It is maybe a standard in the US, but it may not in other places. The standard in my country is to put parenthesis to exclude any ambiguity, anything else is false. Is that really the standard in your country? I don't care about trying to say whose standard is more correct, because that doesn't make sense. However, I am interested in any nation's math representative (lol) declaring official conventions for a country. I'm a programmer so I just parenthesize everything anyway just in case whatever compiler I'm using has a different convention for some ungodly reason.
Well I won't say it is a convention, because I have no idea if its true or not. But I have never learned (in elementary school) or heard about anything else than putting parenthesis every time an ambiguity is possible (maybe except when the fraction is properly written on paper). But I put parenthesis everywhere when I program to avoid any confusion.
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On April 09 2011 05:29 Ropid wrote:Show nested quote +On April 09 2011 05:25 chonkyfire wrote:
48
_________ = what's the answer?
2(9+3) This would be 2, and for 48 --- (9 + 3) 2 it is 288.
It boils down to whether or not multiplication by juxtaposition has priority or not, which would lead to the (9 + 3) to be either in the denominator or the numerator.
If I were told that the presented problem was 100% written correctly with only 1 correct interpretation, I would believe the term to be in the denominator, and the answer to be 2. If it were to be in the numerator, it would be written next to 48, so it would be 48(9+3)/2, but is is not. The majority of people who see 1/2x as 1/(2x) showing that most believe multiplication by juxtaposition has priority yet majority believes its 288....
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On April 09 2011 05:35 Roggay wrote:Show nested quote +On April 09 2011 05:13 Sluggy wrote:On April 09 2011 05:02 Roggay wrote:On April 09 2011 04:58 Sluggy wrote:On April 09 2011 04:52 Roggay wrote:On April 09 2011 04:48 Sluggy wrote:On April 09 2011 04:37 Shadowcloak wrote:
why does it ask math at university lvl this is high school material order of operations is elementary school material. The interest of the poll is how people studying math at a high level can overlook the standard way of evaluating expressions. It doesn't say anything about the ability of these people to understand elementary school concepts, but it does serve as a reminder that there are ambiguities in the way things can be evaluated and that is why standardized conventions exist in the first place. The standard convention requires parenthesis for such cases, atleast its what they taught me at school here, and its more logic this way. Here standard convention means the accepted way of handling things. The standard at your school could be to parenthesize everything so that no ambiguities can exist, but in general you don't need parenthesis to evaluate it if you follow a convention. The standard convention says division and multiplication have the same precedence so how do you choose? The standard is to then evaluate expressions from left to right if the precedence is the same. Ambiguity is eliminated after that. I could state my own convention that once precedence is established to evaluate from right to left, but it wouldn't be standard. It is maybe a standard in the US, but it may not in other places. The standard in my country is to put parenthesis to exclude any ambiguity, anything else is false. Is that really the standard in your country? I don't care about trying to say whose standard is more correct, because that doesn't make sense. However, I am interested in any nation's math representative (lol) declaring official conventions for a country. I'm a programmer so I just parenthesize everything anyway just in case whatever compiler I'm using has a different convention for some ungodly reason. Well I won't say it is a convention, because I have no idea if its true or not. But I have never learned (in elementary school) or heard about anything else than putting parenthesis every time an ambiguity is possible (maybe except when the fraction is properly written on paper). But I put parenthesis everywhere when I program to avoid any confusion.
Yeah I haven't learned any acronym or stuff ever on priority... Just that multiplication comes over addition, and that parenthesis are pretty useful. And I have done quite a bit of maths myself to say the least...
I also think this thread is the most retarded one on tl, worse than sc2 lr thread, the power outage lr thread, shine winning over bisu/stork etc... I hope nobody considers that sort of stuff math, after that no wonder some people hate maths...
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On April 09 2011 05:31 chonkyfire wrote:Show nested quote +On April 09 2011 05:29 Ropid wrote:On April 09 2011 05:25 chonkyfire wrote:
48
_________ = what's the answer?
2(9+3) This would be 2, and for 48 --- (9 + 3) 2 it is 288. yeah so you'd need brackets around (48/2)
But why? 
48
--- (9 + 3)
2
is
48 (9 + 3)
-------------
2
is
48 * 12
----------
2
is
576
-----
2
is 288.
What's also true is:
48
--- (9 + 3)
2
is
24 (9 + 3)
is
24 * 12
is 288.
[After typing all this: writing divisions from top to bottom with that horizontal line is really not built to be used without special typesetting software or drawn with pen and paper.]
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On April 09 2011 05:40 Ropid wrote:Show nested quote +On April 09 2011 05:31 chonkyfire wrote:On April 09 2011 05:29 Ropid wrote:On April 09 2011 05:25 chonkyfire wrote:
48
_________ = what's the answer?
2(9+3) This would be 2, and for 48 --- (9 + 3) 2 it is 288. yeah so you'd need brackets around (48/2) But why? 48 --- (9 + 3) 2 is 48 (9 + 3) ------------- 2 is 48 * 12 ---------- 2 is 576 ----- 2 is 288. What's also true is: 48 --- (9 + 3) 2 is 24 (9 + 3) is 24 * 12 is 288.
that's a pretty good point
i don't care anymore
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i think the bodybuilders win?!!?
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On April 09 2011 05:39 corumjhaelen wrote:Show nested quote +On April 09 2011 05:35 Roggay wrote:On April 09 2011 05:13 Sluggy wrote:On April 09 2011 05:02 Roggay wrote:On April 09 2011 04:58 Sluggy wrote:On April 09 2011 04:52 Roggay wrote:On April 09 2011 04:48 Sluggy wrote:On April 09 2011 04:37 Shadowcloak wrote:
why does it ask math at university lvl this is high school material order of operations is elementary school material. The interest of the poll is how people studying math at a high level can overlook the standard way of evaluating expressions. It doesn't say anything about the ability of these people to understand elementary school concepts, but it does serve as a reminder that there are ambiguities in the way things can be evaluated and that is why standardized conventions exist in the first place. The standard convention requires parenthesis for such cases, atleast its what they taught me at school here, and its more logic this way. Here standard convention means the accepted way of handling things. The standard at your school could be to parenthesize everything so that no ambiguities can exist, but in general you don't need parenthesis to evaluate it if you follow a convention. The standard convention says division and multiplication have the same precedence so how do you choose? The standard is to then evaluate expressions from left to right if the precedence is the same. Ambiguity is eliminated after that. I could state my own convention that once precedence is established to evaluate from right to left, but it wouldn't be standard. It is maybe a standard in the US, but it may not in other places. The standard in my country is to put parenthesis to exclude any ambiguity, anything else is false. Is that really the standard in your country? I don't care about trying to say whose standard is more correct, because that doesn't make sense. However, I am interested in any nation's math representative (lol) declaring official conventions for a country. I'm a programmer so I just parenthesize everything anyway just in case whatever compiler I'm using has a different convention for some ungodly reason. Well I won't say it is a convention, because I have no idea if its true or not. But I have never learned (in elementary school) or heard about anything else than putting parenthesis every time an ambiguity is possible (maybe except when the fraction is properly written on paper). But I put parenthesis everywhere when I program to avoid any confusion. Yeah I haven't learned any acronym or stuff ever on priority... Just that multiplication comes over addition, and that parenthesis are pretty useful. And I have done quite a bit of maths myself to say the least... I also think this thread is the most retarded one on tl, worse than sc2 lr thread, the power outage lr thread, shine winning over bisu/stork etc... I hope nobody considers that sort of stuff math, after that no wonder some people hate maths...
I'm more interested in the aspects of math that involve formalizing ideas/proofs etc... Understanding the need for standards and differences in conventions is important. It is an annoying pain in the ass, but important.
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On April 09 2011 05:31 chonkyfire wrote:Show nested quote +On April 09 2011 05:29 Ropid wrote:On April 09 2011 05:25 chonkyfire wrote:
48
_________ = what's the answer?
2(9+3) This would be 2, and for 48 --- (9 + 3) 2 it is 288. yeah so you'd need brackets around (48/2)
If it were written that way, sure.... one has the option of putting brackets but the OP has it written very clearly 48÷2(9+3)
no '/'. Therefore, its obviously 288 and no brackets or parens are needed.
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On April 09 2011 05:52 Crushgroove wrote:Show nested quote +On April 09 2011 05:31 chonkyfire wrote:On April 09 2011 05:29 Ropid wrote:On April 09 2011 05:25 chonkyfire wrote:
48
_________ = what's the answer?
2(9+3) This would be 2, and for 48 --- (9 + 3) 2 it is 288. yeah so you'd need brackets around (48/2) If it were written that way, sure.... one has the option of putting brackets but the OP has it written very clearly 48÷2(9+3) no '/'. Therefore, its obviously 288 and no brackets or parens are needed.
MasterOfChaos has found mathematicians that use their stuff as if the answer is 2 and not 288. In my opinion it is really untidy to write it like "48÷2(9+3)" and not "48÷2×(9+3)" (I searched for the × instead of the *, because you also don't like the use of / over ÷).
On April 09 2011 05:23 MasterOfChaos wrote:At least one reputable source, namely the American Mathematical Society used high priority for omitted multiplication signs in their publications. Show nested quote +We linearize simple formulas, using the rule that multiplication indicated by juxtaposition is carried out before division. For example, your TeX-coded display $${1\over{2\pi i}}\int_\Gamma {f(t)\over (t-z)}dt$$ is likely to be converted to $(1/2\pi i)\int_\Gamma f(t)(t-z)^{-1}dt$ in our production process. http://replay.waybackmachine.org/20011201061315/http://www.ams.org/authors/guide-reviewers.html
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Man, I was so sure I was getting it wrong when I picked 288. because to me that answer seemed so obvious that I was sure I was missing something.
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I've always learned BEDMAS where it's Brackets Exponents then Multiplication and Division from left to right then Adding and Subtracting left to right. By that it should be 288 which is correct?
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More from that Dr. Math guy, http://mathforum.org/library/drmath/view/72166.html:
The problem is that some calculators that allow multiplications to
be implied as in the former case treat that as a higher precedence
operation (as some algebra texts say), while others treat all
multiplications alike (as most texts do, in my experience). You can
read a little about that here:
Would be interesting to know the percentage of textbooks that teach the higher precedence for implicit multiplication and if it is country specific. I don't remember ever being taught that implicit multiplication had higher priority than explicit.
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Aren't the two equations from the last poll equivalent? I didn't really interpret it one way or another. Its just two ways of writing the same thing.
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not so much a math problem but a where are the parentheses or * sign problem
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On April 09 2011 06:12 AcrylicMass wrote:
Aren't the two equations from the last poll equivalent? I didn't really interpret it one way or another. Its just two ways of writing the same thing.
You're asking if these equations are equivalent:
(1/2) * x
1/(2*x)
If you're ever unsure just plug some numbers in for x and see what you get
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EPT
