EPTbut really guys, really?
A Simple Math Problem? - Page 69
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oneofthem
Cayman Islands24199 Posts
but really guys, really? | ||
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Antisocialmunky
United States5913 Posts
* + 9 3 / 48 2 or / 48 * 2 + 9 3 Because ambiguous infix without assumed Left To Right is silly unless you're making a thread to trick people on Order of Operations. | ||
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valer0
5 Posts
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CrayonKing
Cambodia124 Posts
Having the 2(9+3) makes it seem you like you have to multiple it first but really if you look at it like 48 / 2 x 12 makes it look a little better | ||
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Kazius
Israel1456 Posts
Division is multiplication by a number to the power of minus one. Of course it has the same priority as multiplication, as the Power action has higher priority. Anything else is just wrong. Rephrasing the equations without any change with "==" denoting equivalence: 48÷2(9+3) == 48 * 2^(-1) * (9 + 3) 1/2x == 1 * 2^(-1) * x Writing 'xy' is shorthand for 'x * y', it does not denote anything in prioritization, it denotes being too lazy to add a multiplication symbol. I would say this was a troll thread, but so many people got it wrong that frankly, I am shocked in to writing this. | ||
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valaki
Hungary2476 Posts
On April 08 2011 22:11 CrayonKing wrote: This thread is really dumb because it depends on how you interpret it. You can't really interpret any other way tho. | ||
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sleepingdog
Austria6145 Posts
On April 08 2011 22:11 CrayonKing wrote: This thread is really dumb because it depends on how you interpret it. Not it's not dumb because that's the interesting thing about it. That even the "language" of maths leaves open space for interpretation because of conventional deviation from "rules". In fact, the real fail posts here are indeed those that claim that either one is 100% correct. Because they fail to even recognize the underlying problem. | ||
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Ace
United States16096 Posts
On April 08 2011 22:00 ChrisXIV wrote: I can write 48 as "a", 2 as "b" and (9+3) as "c"... 48/2(9+3)=a/bc ...so it's still the same thing basically. Edit: Lol @ poll above me. Subbing numbers into his example doesn't mean they are the same. You are talking about different operations here. Variable multiplication and division have no "implying" the way he wrote it. The OP example does for some people. | ||
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biomech
Germany380 Posts
On April 08 2011 22:07 Sated wrote: Brackets (aka. parenthesis), then orders of magnitude (aka. powers), then division and multiplication (from left-to-right) and then addition and subtraction (from left-to-right). That's what i remembered from 5th class or someting, and brought me straight to 288. Due to the massive post count (and the fact that most ppl voted 288) i first thought it was actually wrong... well, i'm glad it was not ^_^ [edit] yay, 100th post! | ||
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shadowy
Bulgaria305 Posts
Arithmetics - you end up with 288 (By the order of operations, BODMAS, PUDMASS whatever they taught you) Algebra - the score is 2 - 2(9+3) can not be broken apart and represents a fraction, hence it must be dealt with first. I hope I summed it real short and simple. | ||
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Ceril
Sweden1343 Posts
48/2(9+3) since division operation takes up one spot but consists of two numbers as a whole. 48/2 <-This is one unit, either 48 or 2 on themselves is not a number all division needs to be read with missing parenthesis to make it come out right, you encapsulate it? (48/2) <-With the parenthesis added we now see clearly. (48/2)(9+3) our parenthesis(9*3) is one unit. (48/2)=24 a/b =c to make it into go with multiplying So 48/2(9+3) => (48/2)(9+3) =>(24)(12) 24*12=>288 I'am not a teacher. But I've been told to add the silent operators if I'am confused by a statement. And that is what I'am doing here. Since we have both multiplication and division present we need to either make all multiplication into fractions or resolve all division so we can multiply it. The problem steems from many reading 2x as one unit when it is not since the 2 is part of the division unit and should not be read on itself. Iam remembering calculus teacher talking about this exact thing. | ||
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mechavoc
United States664 Posts
I work with a bunch of analysts (Smart math people who do math for a living) and the responses (without seeing the two options ) were a mix between 2 and 288. The consensus is the way the question is written is ambiguous mainly due to the division sign. Most of the time you see the / (as a fraction) So it could be read as 24*(12) or 48 -------- 24 | ||
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mechavoc
United States664 Posts
On April 08 2011 22:15 valaki wrote: You can't really interpret any other way tho. I would disagree | ||
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Supamang
United States2298 Posts
On April 08 2011 22:16 sleepingdog wrote: Not it's not dumb because that's the interesting thing about it. That even the "language" of maths leaves open space for interpretation because of conventional deviation from "rules". In fact, the real fail posts here are indeed those that claim that either one is 100% correct. Because they fail to even recognize the underlying problem. Completely agreed. People here are being so damn full of themselves when stating what they think is proof, but they dont even realize that others who are waayyyy better at math than any of us also dont have a definitive answer to this. Fact of the matter is, some people prioritize Multiplication By Juxtaposition over Multiplication or Division by Operators. Most of the time "12x" or "12(x)" is seen as one term while "12 * x" is seen as two. When you come up with "48 / 2(9 +3)" its completely logical that you can come up with "48 / 2 * 12 = 288", but at the same time its completely understandable that others come up with "48 / (2 * 12) = 2". So dont be all "WTF is wrong with you people" and dont infer that people who disagree with your answer are idiots. Get off your fucking high horses and realize that whichever answer ends up being correct, the people who got it wrong have completely legitimate reasons as to why they thought otherwise. | ||
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StarStruck
25339 Posts
On April 08 2011 14:38 moltenlead wrote: I can see this getting to 100 pages since ideas are being recycled every few pages. The question is not stated clearly, which is the fundamental cause of all our confusion. If you interpret (9+3) to be a term separate from the 2, you get 288. If you interpret (9+3) as attached to the 2, then you get 2. It's been said over 100 times already. -.- When I look at the problem i see NO algebra, so throw out the imaginary parenthesizes; 2 cannot belong to (9+3). Yes normally there would be a * between the 2 and 9, but I've seen many middle school textbooks in print without displaying the *. Bad form surely, but we have to consider what the problem is trying to teach and that can only be one thing. On April 08 2011 14:45 Fatalize wrote: This is just plain stupid. The symbol ÷ is almost never used in mathematics. We use fractions because it's much more clearer for less parenthesis. Therefore this poll is completely useless. You could get both 2 and 288 just by thinking OP forgot to put parenthesis. This is just to confuse people and it doesn't show anything about intelligence or whatever. And i'm in an engineering school. The question isn't written in the proper form for you to be writing it as a fraction. The ÷ should be the biggest tell of what kind of problem it is. Have any of you ever had teachers back in school tell you to write it out any differently? I highly doubt it. That only comes into play when you start doing algebra and solving for x and y. | ||
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VIB
Brazil3567 Posts
On April 08 2011 22:33 mechavoc wrote: You would be perfectly correct, except that you made a typo and inverted the 24/48 This seems simple but is actually pretty interesting. I work with a bunch of analysts (Smart math people who do math for a living) and the responses (without seeing the two options ) were a mix between 2 and 288. The consensus is the way the question is written is ambiguous mainly due to the division sign. Most of the time you see the / (as a fraction) So it could be read as 24*(12) or 24 -------- 48  | ||
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sulliwan
85 Posts
Having implied multiplication take priority is a useful thing, since most of the time, you can make your math clearer and more concise in that way. Just make sure you specify it before you write anything else.  | ||
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Antisocialmunky
United States5913 Posts
On April 08 2011 22:15 valaki wrote: You can't really interpret any other way tho. You can construct 2 different pre-fix or post-fix notions which implies multiple valid syntax trees for it so in the strictest since of the word, it is ambiguous if you do not assume LtR. | ||
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ChrisXIV
Austria3553 Posts
On April 08 2011 22:32 Ceril wrote: I think that I've been told division takes precendece over mulitplication if you have both present. Since division consists of 2 parts to make a whole, wheras multiplication is 1 part for the whole. Division: a/b =c a=dividend b=divisor c=qoutatient. on their own a and b means nothing, a/b needs to be read as one unit, made into c to go with multiplication. 2*2=(2/1)*(2/1)=(2/1)/(1/2)=(4/1)=4 2*3=(2/1)*(3/1)=(3/1)*(2/1)=(3/1)/(1/2)=(2/1)/(1/3)=(6/1)=6 I don't get what you are trying to say, sry T_T. Edit: On April 08 2011 22:44 lofung wrote: this is a horribly defined question. as a math major i refuse to answer until further clarifaction. That's the point. ^^ | ||
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lofung
Hong Kong298 Posts
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