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On April 09 2011 07:19 MasterOfChaos wrote:Show nested quote +On April 09 2011 07:06 Zealot)KT( wrote:
Everyone knows this is 58, and not 34. Now compare it to the problem in the OP:
48 ÷ 2 · (9 + 3) = ? This is not identical to the problem in the OP. The OP omitted the "·". The difference in interpretation hinges exactly on the effect of this omission. Many people give this implicit multiplication a higher priority. Even the publication guidelines of the American Mathematical Society contained that convention, so it's not just people who're too stupid to know maths.
Not really!
Most people answering here are prioritizing multiplication but why?
AMS as you posted clearly states when and why they use such notation and how it's supposed to read that. This applies to their documents(s) and there's nothing wrong with that, but we didn't get such information here = use standard rules (dividing and multiplication are equal, read left to right).
As someone just noted above, this "grammar" is basic and experts know that they can use it differently in some cases, but this thread is hardly people who're too expert in math....
You said it like "many people prioritize multiplication and so do AMS" but it's "many people priorize multiplication God knows why, and AMS do that because they defined a rule for their papers".
And don't get me wrong, I voted both 288 and 1/(2x). Why? Because question was how I usually read (having math on studies I do use such different "grammar" rule for this particular thing). But approaching more complicated question I never want to get lost: left to right, step by step is way to go on any exam on studies. When I'm having a bad day I do put extra parenthesis and solve slowly to avoid mistakes like many people just did in this thread (not saying all did).
And to say that again, I did learned in school first the order and few years later that you usually dont use * symbol when multiplying parenthesis or variables. But learning this rule I also learned: parenthesis are always for a reason and their reason is modifying order. The key in solvng this: 48 ÷ 2 · (9 + 3) is that leaving parenthesis (which is first thing you do, as it wants you to change order), that leaving parenthesis does not mean you should immediately multiply! multiplying have it's place in solving order so there is still 48 ÷ 2 · (12) = 48 ÷ 2 · 12. Left to right and you did it right.
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I've tried to read through a few pages before responding as the mod edit said, but I'm still confused as to why there is a debate over this.
I see no ambiguity about this and no possible way you could interpret it otherwise. It is 48 * 1/2 * (9+3). It makes no sense to evaluate it as 48 * 1/2 * 1/(9+3). You're just completely making up a value at that point.
1/2x is obviously (1/2)*x for the same reasons. 1/2 * 1/x is a ridiculous way to interpret it.
There are some debates you can try to have with mathematics. These are NOT some of them.
This should be an "oops" or "I guess I didn't know that's how math notation works" thread, not a debate thread.
Currently studying mathematics at my university.
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So its 288 yes? Don't see how people got it wrong if they are studying Maths at a uni level. I learnt BOMDAS in grade 4.
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Kentor
United States5784 Posts
On April 09 2011 09:12 Befree wrote:
I've tried to read through a few pages before responding as the mod edit said, but I'm still confused as to why there is a debate over this.
I see no ambiguity about this and no possible way you could interpret it otherwise. It is 48 * 1/2 * (9+3). It makes no sense to evaluate it as 48 * 1/2 * 1/(9+3). You're just completely making up a value at that point.
1/2x is obviously (1/2)*x for the same reasons. 1/2 * 1/x is a ridiculous way to interpret it.
There are some debates you can try to have with mathematics. These are NOT some of them.
This should be an "oops" or "I guess I didn't know that's how math notation works" thread, not a debate thread.
Currently studying mathematics at my university.
it's not ridiculous at all. why are you so bitter? the ridicule belongs to the way the problem is written in the first place.
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On April 09 2011 09:12 Befree wrote:
I've tried to read through a few pages before responding as the mod edit said, but I'm still confused as to why there is a debate over this.
I see no ambiguity about this and no possible way you could interpret it otherwise. It is 48 * 1/2 * (9+3). It makes no sense to evaluate it as 48 * 1/2 * 1/(9+3). You're just completely making up a value at that point.
1/2x is obviously (1/2)*x for the same reasons. 1/2 * 1/x is a ridiculous way to interpret it.
There are some debates you can try to have with mathematics. These are NOT some of them.
This should be an "oops" or "I guess I didn't know that's how math notation works" thread, not a debate thread.
Currently studying mathematics at my university.
I guess you completely missed out on multiplication by juxtaposition? The only correct answer is both 2 and 288 are correct and it shouldn't matter why. As long as that's the answer for you who cares, both answers are arrived at using correct mathematical conventions. And just taking anecdotal evidence, you think a non-ambiguous mathematical expression would spawn a 90+ page debate on TL?
Whats really the problem is if you can't arrive at 2 or 288, or if you think that multiplication/division or addition/subtraction have to go in a specific order when using BEDMAS or whatever your mnemonic is.
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For those who think 2 is correct answer should read what realills wrote on page 62.
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I feel that my last post won't meet with any understanding from the "=2" group so I will just write this story instead.
I had many different math classes on studies. This on professor wasn't an as and I liked him very much. On exams we were allowed to do all king of stuff that was out of usual conventions if we felt it's easier for us to write/solve that ways.
While writing graphs we could used axis differently.
We could switch rows with columns of matrixes.
If someone would like to have some fun I'm sure he could switch + with * symbols (or any other way).
Probably switching to hex and solving that way would be allowed too.
Why?
It's a free world, he said.
But there was just one little rule everyone had to obey.
If you didn't write down rules that you were going to use, he was assuming usual mathematical conventions.
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I am going to repost this from the previous page so hopefully people who continue to mindlessly invoke "BEDMAS BEDMAS BEDMAS" will stop questioning the intelligence of the people who voted for 2.
![[image loading]](http://i.imgur.com/aP7Gg.jpg)
Quote from the image:
"Multiplication by juxtaposition has priority over division and multiplication represented by *."
Why are people still being so damn derisive in their responses? Jesus fucking h Christ. People who say its 288 consider the equation to just be "48 / 2 * 12". This is perfectly reasonable. People who say its 2 consider multiplication by juxtaposition to have priority. This is also perfectly reasonable.
Its already been stated before in this thread that there are people who have studied math much more extensively than any of us at TL who dont have a definitive answer to this problem. The correct answer to this problem has also already been stated in this thread, that is: "Awful, ambiguous fucking question. Restate it before 90 pages worth of pretentious posters try to make their opposition look like idiots."
Why are people still arguing here?
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On April 09 2011 09:35 Supamang wrote:I am going to repost this from the previous page so hopefully people who continue to mindlessly invoke "BEDMAS BEDMAS BEDMAS" will stop questioning the intelligence of the people who voted for 2. Quote from the image: "Multiplication by juxtaposition has priority over division and multiplication represented by *." Why are people still being so damn derisive in their responses? Jesus fucking h Christ. People who say its 288 consider the equation to just be "48 / 2 * 12". This is perfectly reasonable. People who say its 2 consider multiplication by juxtaposition to have priority. This is also perfectly reasonable. Its already been stated before in this thread that there are people who have studied math much more extensively than any of us at TL who dont have a definitive answer to this problem. The correct answer to this problem has also already been stated in this thread, that is: "Awful, ambiguous fucking question. Restate it before 90 pages worth of pretentious posters try to make their opposition look like idiots." Why are people still arguing here?
That picture doesnt really mean anything. Its just saying what the convention is for that particular calc. Its just saying that you should be careful about how you write in the expression.
It even says that the TI - 86 does not use that rule. The TI - 85 does, but the TI - 86 does not.
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The thing is, if you consider multiplication by juxtaposition to have priority, you are treating real numbers as not being a field, which we know they are. In this case, multiplication and division happens at the same time.
Beside, programing code are often flawed, why use their logic and train of thought into a math question?
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48/2(9+3)
= 48 * 0.5 * 12
= 288
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On April 09 2011 09:35 Supamang wrote: People who say its 2 consider multiplication by juxtaposition to have priority. This is also perfectly reasonable.
Why are people still arguing here?
Because if you interpret the answer as 2, you are wrong. Nothing ambiguous lol. If that was on an international exam, or any sort, or any exam of any sort, there is one answer, 288. Why are you here defending people who don't understand Math?
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For people who say multiplicative distributive property says 2(9+3) is 18+6=24 and therefore 48/2(9+3)=2
here's a question... why aren't you distributing 24(9+3) = 216+72=288
cuz 48/2 is 24
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On April 09 2011 09:43 leo23 wrote:
48/2(9+3)
= 48 * 0.5 * 12
= 288
WTF?!
You've never been taught about the order of doing things in math?
48/2(9+3) = 48/(2*9+2*3) = 48/24 = 2
It's pretty simple.
Edit:
I'm a humanist. Got lowest passable grade in math in highschool.
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On April 09 2011 09:47 Pufftrees wrote:Show nested quote +On April 09 2011 09:35 Supamang wrote: People who say its 2 consider multiplication by juxtaposition to have priority. This is also perfectly reasonable.
Why are people still arguing here? Because if you interpret the answer as 2, you are wrong. Nothing ambiguous lol. If that was on an international exam, or any sort, or any exam of any sort, there is one answer, 288. Why are you here defending people who don't understand Math?
I have exams where multiplication by juxtaposition takes priority over simply division and multiplication.
In my business school, multiplication by juxtaposition takes priority 100% of the time. This is how it is being done with my financial equations as well.
Its just how my UNIVERSITY teaches it.
It seems like a bunch of Universities work this way to, while others do not...
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On April 09 2011 09:42 Rtran10 wrote:Show nested quote +On April 09 2011 09:35 Supamang wrote:I am going to repost this from the previous page so hopefully people who continue to mindlessly invoke "BEDMAS BEDMAS BEDMAS" will stop questioning the intelligence of the people who voted for 2. Quote from the image: "Multiplication by juxtaposition has priority over division and multiplication represented by *." Why are people still being so damn derisive in their responses? Jesus fucking h Christ. People who say its 288 consider the equation to just be "48 / 2 * 12". This is perfectly reasonable. People who say its 2 consider multiplication by juxtaposition to have priority. This is also perfectly reasonable. Its already been stated before in this thread that there are people who have studied math much more extensively than any of us at TL who dont have a definitive answer to this problem. The correct answer to this problem has also already been stated in this thread, that is: "Awful, ambiguous fucking question. Restate it before 90 pages worth of pretentious posters try to make their opposition look like idiots." Why are people still arguing here? That picture doesnt really mean anything. Its just saying what the convention is for that particular calc. Its just saying that you should be careful about how you write in the expression. It even says that the TI - 86 does not use that rule. The TI - 85 does, but the TI - 86 does not.
...wtf man. You ignored the main point of my post. The main point is, people who think the answer is 2 have a reason as to why they think so. What I am trying to say is that both answers are perfectly reasonable, and yet so many people in this thread think that whoever thinks differently from them somehow missed elementary math class.
And the fact that the TI-85 does use this rule while the TI-86 doesnt further supports my point. Both answers are fine considering the terribad framing of the original question.
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This isn't a maths problem. It's a typesetting problem. Had it been laid out as either
48
------------- = 2
2 ( 9 + 3)
or
48
--- (9 + 3) = 288
2
the answer would have been unambiguous. It could also be unambiguously stated on one line in RPN:
2 = 48 2 9 3 + * /
288 = 48 2 / 9 3 + *
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On April 09 2011 09:55 Insanious wrote:+ Show Spoiler +On April 09 2011 09:47 Pufftrees wrote:Show nested quote +On April 09 2011 09:35 Supamang wrote: People who say its 2 consider multiplication by juxtaposition to have priority. This is also perfectly reasonable.
Why are people still arguing here? Because if you interpret the answer as 2, you are wrong. Nothing ambiguous lol. If that was on an international exam, or any sort, or any exam of any sort, there is one answer, 288. Why are you here defending people who don't understand Math? I have exams where multiplication by juxtaposition takes priority over simply division and multiplication. In my business school, multiplication by juxtaposition takes priority 100% of the time. This is how it is being done with my financial equations as well. Its just how my UNIVERSITY teaches it. It seems like a bunch of Universities work this way to, while others do not...
Name of your university please?
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So this questions is basically Math's "Po TAY TOE" "PO TA DO"
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i like this thread. The math expression is just an ambiguous one that you can only answer from a certain assumption about the implied rules. Both sides are right / wrong until the mathematics community decides on a verdict for this (juxtaposition taking precedence would solve this but it is not a set in stone rule) and it remains an enigma. What makes me lol though is that people are still coming into this massive thread trying to say that it is not ambiguous. Another great part is the PEDMAS or whatever acronym they were taught. We had something of the sort as well but that rule was instantly dropped as soon as you reach high school to teach you that multiplication / division are equal and so are + and -.
On April 09 2011 10:02 s0Li wrote:
So this questions is basically Math's "Po TAY TOE" "PO TA DO"
excellent summary imo.
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EPT
