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Rev. Zen

48÷2(9+3) = ?

84 posts in this topic

And why the question would ever be asked in first place! Seriously Rev, WHAT DOES IT MEAN?! :crazy5hz:

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And why the question would ever be asked in first place! Seriously Rev, WHAT DOES IT MEAN?! :crazy5hz:

622755[/snapback]

 

I do not know what the calculation is for. I read somewhere that it was a 5th grade math problem that a parent had posted on a forum because they were confused about teh ambiguity of it. I did not think it was ambiguous at all, but I was stunned, after searching on the interent, that so many other people were arguing that the answer was 2 and not 288. There two forums I visited that had polls and both polls were split 50/50 with "2" actually having a little bit of a lead!

 

People were plugging it into TI-85 calculators and getting "2" while others were pluggnif it into Casio calculators and getting "288"

 

16h6ja8.jpg?1302454815

 

There are video memes of this now.

 

B5XfCE_x6S4&feature=related

 

It is replacing the airplane on a treadmill problem as the predominate internet preoccupation!!!!

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omg.... I loved it when it was just the babies chattering but this remake is awesome!

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the issue comes up because when the equation is written poorly to create confusion 48÷2(9+3).

 

It comes down to how this portion of the equation is written 2(9+3).

 

most that do alot of algebra and physics calculations key in on the distribution of the 2 throughout the monomial. If it was written z ÷ 2(x + y). You could also write the equation z/2(x+y). In algebra we look at the term 2(x+y) as a simplified monomial that shouldn't be split up because that's the convention.

 

We go thru our algebra training and when it comes to distribution problems and simplification in our algbra brains it appears that 2(x + y) is a simplified monomial and we automatically want to Unsimplify it reverse engineering wise FIRST OFF because that's how we were taught. 2(x+y) is its OWN algebraic expression.

 

The order of operations isn't in question here. It's the conditioning of our brains when we went thru algebra. We are conditioned to automatically distribute the 2 thru the monomial since it is written like it was simplified from that root. (2x + 2y)

 

so if you wrote the equation as it appears that its been simplified to z ÷ (2x + 2y) the confusion is evident and you come to the same wrong conclusion. The issue here isn't order of operations. It's how the equation is written to take advantage of a preconditioned teaching weakness.

 

We need mathematics to be more standard. We are using several different symbols to depict the same thing and it creates confusion for our children. I can see why it's become like this to help print books easier, but with the new technologies we have, why not goto one standard way of writing equations to avoid any confusion?

 

I think all equations should be written in fractional form in print. No more / or ÷ there should be no assumed rules like 2(x+y) = 2 * (x+y).

 

Here's hoping for a better world. lol

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Certainly teaching practices are a significant root of this issue as is evidenced by the large portion of people that jump to the wrong conclusion. I know I always ran into issues with math teachers because I was able to do equations in ways that baffled them. I was typically able to get to answers faster and more consistantly than my fellow students using methods of my own and without need to show/do a lot of steps on paper. For a quick and dirty example I was able to do my 3 hour grade 9 math exam in 15 minutes for an end grade of 97% (I lost marks for not following the formats "correctly" according to the teacher). My point being, the "methods" taught by the curriculum following teachers are not neccessarily the best way to solve a problem. I couldn't for the life of me force myself to use the methods taught to the general class. My mind just didn't work that way. I would more often get the answer wrong trying to force myself into those methods.

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i have to agree with you fyre......and we both know how much that hurts me :D

 

 

i had horrible problems with math teachers in school...then my dad started traveling a lot so i home schooled and went with him. home school is a breeze when u can work at your own pace and figure out stuff in your own ways. however the algebra book just didnt make sense to me after getting part way thru it....so my friends basically tutored me thru algebra so i could finish it and most of em just used shortcuts anyways which made a lot more sense to me than what any math teachers ever tried to teach me.

 

 

fyi.....i hate algebra....but i did the part in parentheses first then did it in order from left to right. i just thought it was common sense to do it that way until i saw all the debate. 288 ftw

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Have to agree with both Mire and Fyre on this. I hated math in HS. I thought it was ridiculous that the teachers would mark you down for not working problems out step by step as they showed you, regardless that you came up with the same answer in twelve steps less than the "proper" way. My Trig and Algebra 2 classes I ended up passing with B's because I refused to do my work as taught. Didn't even bother taking Calc, wanted to avoid that headache all together.

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I think most people have their own little ways for doing math. Just as one example, when I add multi-digit numbers:

 

68 + 47 = 70+45 = 100+15 = 115

 

This just happens automatically in my head, and it happens almost instantaneously. Its much faster for me than any other method I've ever learned. Most of the people I've tried to explain this method to look at me like I'm crazy. Its a little overkill for 2 digit numbers, but for me it makes it easy to perform operations on 4+ digit numbers in my head.

 

I've never been a fan of rote memorization, when you memorize a defined set of rules or sequences you can perform those operations very quickly, but it becomes much harder to do anything that isn't within that defined set. If you truly understand the mechanics, why things work the way they do, and how they apply in the real world, you are equipped to handle nearly anything. It may take you a little longer sometimes, but you aren't limited to what you memorized.

 

In my college trig and calculus classes I slacked off hardcore. I didn't do all the homework and memorize all the formulas and I didn't spend much time studying, but I knew how the math worked. I knew why the formulas were needed, what they accomplished, and how they were formed in the first place. So while I didn't finish every test first, I was always able to work through the math in my own way. Derive the formula that was needed, and verify that I had the correct answer.

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And why the question would ever be asked in first place! Seriously Rev, WHAT DOES IT MEAN?! :crazy5hz:

622755[/snapback]

 

I do not know what the calculation is for. I read somewhere that it was a 5th grade math problem that a parent had posted on a forum because they were confused about teh ambiguity of it. I did not think it was ambiguous at all, but I was stunned, after searching on the interent, that so many other people were arguing that the answer was 2 and not 288. There two forums I visited that had polls and both polls were split 50/50 with "2" actually having a little bit of a lead!

 

People were plugging it into TI-85 calculators and getting "2" while others were pluggnif it into Casio calculators and getting "288"

 

16h6ja8.jpg?1302454815

 

There are video memes of this now.

 

B5XfCE_x6S4&feature=related

 

It is replacing the airplane on a treadmill problem as the predominate internet preoccupation!!!!

622834[/snapback]

 

For a parent to post a 5th grade math problem after doing their own computations and still don't understand what the answer is is astonishing. they must be old people who cant use google quick enough or know what to type to study the Dear Aunt Sally, etc. or realize you go from left to right or even use a TI-80ers calculator. i been off sg website for a few days and this thread has exploded from 2 pages to 4 pages. Ha haz? Next time I make a new thread it will just say..."Godzilla!" and see how many posts it gets! but that's kinda spam...

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I've never been a fan of rote memorization, when you memorize a defined set of rules or sequences you can perform those operations very quickly, but it becomes much harder to do anything that isn't within that defined set.

622991[/snapback]

You would HATE flight school. Some of the random BS I've had to memorize verbatim is ridiculous.

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the numbers you picked were 7 and 3 shultzy

622819[/snapback]

Yes. You are right.

Now find the answer to... 33

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I don't see how an algebra mind set matters. I have done every type of math there is and I see the problem properly.

 

What I do agree with is that the problem could be written in a clearer fashion.

 

(48÷2)(9+3)=

 

If it is written like that nobody will get it wrong. Or at least they better not.

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(48/2)(9+3)

 

(2^(4-1) * 3) * 12

 

24 * 12

 

288

 

=========

 

Also of note, I ran it through Algebrator and Microsoft's Mathematics program. Both come up with 288. I have these because I happen to be taking Algebra 2 in college atm.

 

And btw, the original form plus Arragoth's "clearer" form, both return 288.

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you picked 8 and 2 Schultzy.

 

I think we all see the problem clearly now along with the answer.

 

I was merely trying to give an example of why someone might get the wrong answer that has quite a bit of mathematics background.

 

 

22.4 MeV think about it.

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It is an open ended question, there are multiple correct answers. 2 is not one of them though an 288 is one of them, but only one of them, not the only answer by a longshot.

 

42 is always an acceptable answer to any question...

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I first came up with 2 as well, however if the equation where listed as 48/2*(9+3) then my basic instinct is to go with 288.

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I find it amusing as hell that you guys are arguing over the answer to a math equation. But I might as well add my 2 cents in also. The way I was taught the answer is 288

622614[/snapback]

 

 

You dont have that many fingers and toes :D

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I find it amusing as hell that you guys are arguing over the answer to a math equation. But I might as well add my 2 cents in also. The way I was taught the answer is 288

622614[/snapback]

 

 

You dont have that many fingers and toes :blob:

624036[/snapback]

No, but I am intelligent enough to figure out simple enough math in my head. And for the ones I can't I have my handy dandy TI83S. Just because I act like a blonde doesn't mean I really am Primal :D :):)

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I find it amusing as hell that you guys are arguing over the answer to a math equation. But I might as well add my 2 cents in also. The way I was taught the answer is 288

622614[/snapback]

 

 

You dont have that many fingers and toes :)

624036[/snapback]

No, but I am intelligent enough to figure out simple enough math in my head. And for the ones I can't I have my handy dandy TI83S. Just because I act like a blonde doesn't mean I really am Primal :D :):)

624188[/snapback]

 

You totally missed the point .. look like, act like, male, female blonde or brunette, I would have posted the same thing... Bratz! :blob:

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