Poll: What is the answer to 48/2(9+3)?

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Joseph Webb

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mps4li3n said:
Pyro Paul said:
Here is the problem with that...
how does 48/2(9+3) become 48/2*(9+3)?

2(9+3) is NOT 2 * (9+3)
it is the simplified form of
((2*9)+(2*3))
And that's the problem, obviously not everyone was taught that 2(x+y) and 2*(x+y) aren't the same thing simplified by not bothering with the *

It's all a simple case of grammatical syntax as applied to the way math is written (and make no mistake, the symbols used as as arbitrary as letters, while math is simply the ability to speak).
Listen. If you weren't taught that those aren't the same thing, then you were taught incorrectly. That is all there is to it. There is ONE grammatical syntax to math. JUST ONE. You can bend it to do all sorts of fun things, but if you write something one way, it will ALWAYS mean the same thing. It is up to the individual to understand what it's saying.
 

Taerdin

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Joseph Webb said:
I sincerely hope that you are a child. That is not how the expression is written, I'm right. You're a troll (or someone with an extremely below average IQ), I'm done replying to you.
I'm very sorry that I couldn't help you. I guess I know how my gf feels when she has to deal with problem students that deal with their lack of understanding with anger and misbehaviour.
 

mps4li3n

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Joseph Webb said:
I sincerely hope that you are a child. That is not how the expression is written, I'm right. You're a troll (or someone with an extremely below average IQ), I'm done replying to you.

You don't seem to understand that if whatever authority is in charge of the math symbols decides to use totally different ones tomorrow then they could without changing anything about math at all.

Like when they decided that Pluto wasn't a planet, it didn't change any actual real proprieties of Pluto, just it's arbitrary designation.
 

Joseph Webb

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mps4li3n said:
Joseph Webb said:
I sincerely hope that you are a child. That is not how the expression is written, I'm right. You're a troll (or someone with an extremely below average IQ), I'm done replying to you.

You don't seem to understand that if whatever authority is in charge of the math symbols decides to use totally different ones tomorrow then they could without changing anything about math at all.

Like when they decided that Pluto wasn't a planet, it didn't change any actual real proprieties of Pluto, just it's arbitrary designation.
It does not matter if they change the symbols. It will always mean the same thing. Why do you think that math is a universal language?
 

mps4li3n

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Joseph Webb said:
There is ONE grammatical syntax to math.
Maybe im using 'the word syntax wrong...

But if everyone decides that - means division and / means brackets from now on the that's what they mean, and yet multiplication will still work the same...

So there's no one objectively correct way to write an equation like there is an objective way to actually solve any math problem (as in how do i divide 48 sticks to 2 people equally vs how you should interpret an A for english when i only know french).
 

Taerdin

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Pyro Paul said:
Here is the problem with that...
how does 48/2(9+3) become 48/2*(9+3)?

2(9+3) is NOT 2 * (9+3)
it is the simplified form of
((2*9)+(2*3))

by it your way you break the order of operations and Divide before you complete the Parentheses.
2(9 + 3) is equivalent to 2*(9+3)

2*9 + 2*3 = 18 + 6 = 24

2*(9+3) = 2*12 = 24

But that isn't the question.

The question is 48/2(9+3)

Which is evaluated as such

BEDMAS(or PEMDAS)

Brackets/Parentheses:

48/2(12)

Division & multiplication ( left to right)

24 * 12 = 288


Or if you prefer to distribute

48/2(9/3) = 48/2*9 + 48/2*3 = 288.
 

mps4li3n

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Joseph Webb said:
It does not matter if they change the symbols. It will always mean the same thing. Why do you think that math is a universal language?

Precisely, so if one country uses the lack of the symbol * to mean something while another uses it just as if it's the same as using an * it in no way changes math...

The only problem would be people from the two countries not understanding what the other people are trying to say to them with the formula that uses the lack of an *.

This is what's happening here, except that we don't have any well defined borders.
 

Joseph Webb

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mps4li3n said:
Joseph Webb said:
There is ONE grammatical syntax to math.
Maybe im using 'the word syntax wrong...

But if everyone decides that - means division and / means brackets from now on the that's what they mean, and yet multiplication will still work the same...

So there's no one objectively correct way to write an equation like there is an objective way to actually solve any math problem (as in how do i divide 48 sticks to 2 people equally vs how you should interpret an A for english when i only know french).
Syntax is how you build a paragraph, or in this case, an equation. You're talking about variables. Variables are just that, variable. They can change and mean anything. A letter in any language is a variable. A symbol is a variable. As long as they are given meaning, they can be used in context. It doesn't matter if they switch around what +, -, =, or any other symbol means. As long as everyone knows what it means, everyone will always understand it. The problem with this equation is that people don't understand the basic rules of math. It has NOTHING to do with symbols, hell, it doesn't even have anything to do with the SYNTAX. It has EVERYTHING to do with the RULES or the language. People are not understanding that an equation like 3/2*(8+2) does not equal 3/2(8+2), because they don't understand the basic rules of math. That's all there is to it. There is indeed multiplication in both situations, but they occur at different times. Everyone is taught this in algebra. If you don't understand this basic concept, you must have done poorly in math, or somehow you managed to scrape by without seeing a problem like this (nearly impossible, but whatever). Look up the distributive property, like I've been saying this entire time.
 

yeel

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Joseph Webb said:
yeel said:
Joseph Webb said:
mps4li3n said:
Pontus Hashis said:
The thing is, our teacher told us that multiply and divide comes befor subtraction and addition, but not which comes first, but not which of multiplying or dividing is first... but now I know, and knowing is half the battle!
Because neither does... 48/2 is the same as 48*0.5, if you know that you don't need to have any come first...

The issue here is that it's not clear if the fraction is 48/2 or 48/2(9+3). And obviously people have been taught both variations.
There is no variation, the question is very clear. The question states 48/2(9+3). The answer is 2. The question does not state (48/2)(9+3), which would equal 288. The problem here is that people don't understand fractions. 48 is the numerator, 2(9+3) is the denominator. Please do not provide answers when you don't actually know what it is.
An interesting point Joseph Webb. I do feel there is seems to be a variations in how people interpret the divide sign. Some people believe

1/2 * 1/2 = 1/4

While you would be prone to interpret this as:

1
--------- = 1
2 * (1/2)

especially if i left out the spaces and wrote it down like: '1/2*1/2'

You also seem not to like people posting on this topic who you deem not to understand fractions as well as you do.
I'll be really honest with you, that is the stupidest thing I've ever heard. You don't understand a bit of what I'm saying. THE DISTRIBUTIVE METHOD, DO YOU KNOW WHAT IT IS? If the question were written 1/2(1/2), then the answer would, indeed, be one. Unfortunately, you don't understand mathematical notation.

I'm sorry my posts are getting heated, but seriously, I took math for like, 10 years straight. I had this kind of thing drilled into my head. I know when I'm right.
Sorry man.

So just to let me get this straight;
according to you (and i say this without being condescending) the sign / implies a fraction. But not everything following it is part of that fraction. In honestly didn't know that and apparantly i really don't understand mathematical notation as well as you do.

The reason why some other people who say it's 288 are correcting yet other people who say it's 2 is because it also common for people to not understand PEMDAS. As TiefBlau explained

PEMDAS is a misleading term. Multiplication and division are on the same hierarchy, just like subtraction and addition. You wouldn't say 4-3+2 is 4-(3+2), would you? Of course not.
So my intention was to introduce the following example

1/2 * 1/2 = 1

as a counterexample to your reasoning, because i assumed it would sound stupid to you as well. Which it end up doing, but unfortunately for the wrong reasons, because i wrongly assumed you didn't thought about it all that well.

I don't agree however that people who are disagreeing with you are using flawed logic as you mentioned in a couple of other posts. They simply see / sing is an operator like + and - which, to me, has little to do with logic even though it might not be according to formal mathematical notation you know.
So saying these people are "just wrong", are using flawed logic or making comments about their math skills isn't really helping you to convince them.

I have always seen / simply as an operator. This is what was okay in high school and university, didn't do math there by the way. I was actually surprised so many people thought the answer was 2, what a bunch of idiots ;)

(In the Netherlands it also common to use : as the symbol for division which will probably give some people on this forum a headache.)
 

mps4li3n

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Taerdin said:
Pyro Paul said:
Here is the problem with that...
how does 48/2(9+3) become 48/2*(9+3)?

2(9+3) is NOT 2 * (9+3)
it is the simplified form of
((2*9)+(2*3))

by it your way you break the order of operations and Divide before you complete the Parentheses.
2(9 + 3) is equivalent to 2*(9+3)
That doesn't actually mean you can't attach an extra meaning to the lack of * in relation with other symbols...

And people do if this is any indication: http://www.purplemath.com/modules/orderops2.htm


The problem stems fromt eh fact that in hand writing the / symbol always had superscript and subscript, and thus you could always tell if the part in () was under the fraction or not.

Once computers couldn't do that easily thee does need to be another way to make that clear, and it seems the lack of a * is how some (perhaps the majority of scholars) decided to do it.
 

mps4li3n

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yeel said:
according to you (and i say this without being condescending) the sign / implies a fraction. But not everything following it is part of that fraction. In honestly didn't know that and apparantly i really don't understand mathematical notation as well as you do.
Well notation is not set in stone and never was... a lot of people seem to think that because math is so must mathematical notations...

It's silly really... it's not like everyone who understood that putting 1 and 1 stick together makes 2 sticks used + in between them all of a sudden, or used the same symbol even if they where thousands of miles away, using totally different languages etc.
 

Joseph Webb

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mps4li3n said:
Joseph Webb said:
It does not matter if they change the symbols. It will always mean the same thing. Why do you think that math is a universal language?

Precisely, so if one country uses the lack of the symbol * to mean something while another uses it just as if it's the same as using an * it in no way changes math...

The only problem would be people from the two countries not understanding what the other people are trying to say to them with the formula that uses the lack of an *.

This is what's happening here, except that we don't have any well defined borders.
Yes it does change math. Math works the same all over the world. They will always have some sign letting you know what operation to perform. That's how mathematicians work. They have rules, and they follow them.

Taerdin said:
Pyro Paul said:
Here is the problem with that...
how does 48/2(9+3) become 48/2*(9+3)?

2(9+3) is NOT 2 * (9+3)
it is the simplified form of
((2*9)+(2*3))

by it your way you break the order of operations and Divide before you complete the Parentheses.
2(9 + 3) is equivalent to 2*(9+3)

2*9 + 2*3 = 18 + 6 = 24

2*(9+3) = 2*12 = 24

But that isn't the question.

The question is 48/2(9+3)

Which is evaluated as such

BEDMAS(or PEMDAS)

Brackets/Parentheses:

48/2(12)

Division & multiplication ( left to right)

24 * 12 = 288


Or if you prefer to distribute

48/2(9/3) = 48/2*9 + 48/2*3 = 288.
I'll explain this one last time to you. In the equation 48/2(9+3), 2 is part of the parentheses. Therefore, distributing it amongst the 9 and the 3 comes before EVERYTHING else. It is the FIRST thing you do.
yeel said:
Joseph Webb said:
yeel said:
Joseph Webb said:
mps4li3n said:
Pontus Hashis said:
The thing is, our teacher told us that multiply and divide comes befor subtraction and addition, but not which comes first, but not which of multiplying or dividing is first... but now I know, and knowing is half the battle!
Because neither does... 48/2 is the same as 48*0.5, if you know that you don't need to have any come first...

The issue here is that it's not clear if the fraction is 48/2 or 48/2(9+3). And obviously people have been taught both variations.
There is no variation, the question is very clear. The question states 48/2(9+3). The answer is 2. The question does not state (48/2)(9+3), which would equal 288. The problem here is that people don't understand fractions. 48 is the numerator, 2(9+3) is the denominator. Please do not provide answers when you don't actually know what it is.
An interesting point Joseph Webb. I do feel there is seems to be a variations in how people interpret the divide sign. Some people believe

1/2 * 1/2 = 1/4

While you would be prone to interpret this as:

1
--------- = 1
2 * (1/2)

especially if i left out the spaces and wrote it down like: '1/2*1/2'

You also seem not to like people posting on this topic who you deem not to understand fractions as well as you do.
I'll be really honest with you, that is the stupidest thing I've ever heard. You don't understand a bit of what I'm saying. THE DISTRIBUTIVE METHOD, DO YOU KNOW WHAT IT IS? If the question were written 1/2(1/2), then the answer would, indeed, be one. Unfortunately, you don't understand mathematical notation.

I'm sorry my posts are getting heated, but seriously, I took math for like, 10 years straight. I had this kind of thing drilled into my head. I know when I'm right.
Sorry man.

So just to let me get this straight;
according to you (and i say this without being condescending) the sign / implies a fraction. But not everything following it is part of that fraction. In honestly didn't know that and apparantly i really don't understand mathematical notation as well as you do.

The reason why some other people who say it's 288 are correcting yet other people who say it's 2 is because it also common for people to not understand PEMDAS. As TiefBlau explained

PEMDAS is a misleading term. Multiplication and division are on the same hierarchy, just like subtraction and addition. You wouldn't say 4-3+2 is 4-(3+2), would you? Of course not.
So my intention was to introduce the following example

1/2 * 1/2 = 1

as a counterexample to your reasoning, because i assumed it would sound stupid to you as well. Which it end up doing, but unfortunately for the wrong reasons, because i wrongly assumed you didn't thought about it all that well.

I don't agree however that people who are disagreeing with you are using flawed logic as you mentioned in a couple of other posts. They simply see / sing is an operator like + and - which, to me, has little to do with logic even though it might not be according to formal mathematical notation you know.
So saying these people are "just wrong", are using flawed logic or making comments about their math skills isn't really helping you to convince them.

I have always seen / simply as an operator. This is what was okay in high school and university, didn't do math there by the way. I was actually surprised so many people thought the answer was 2, what a bunch of idiots ;)

(In the Netherlands it also common to use : as the symbol for division which will probably give some people on this forum a headache.)
Don't disagree when I say the people that are getting the answer wrong are using flawed logic. They are using calculators to solve the problem, which utilize flawed logic to solve problems like these. Calculators generally DO NOT distribute automatically. The 2 in the denominator of this problem is a coefficient of (9+3), meaning it belongs inside of those parentheses, but this is implied. Taking a basic algebra class should teach you something like this. Calculators do NOT imply that the 2 is included in the parentheses, and instead treats 48/2 as a fraction, instead of 48/2(9+3). The (9+3) is part of the denominator.
 

mps4li3n

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Joseph Webb said:
People are not understanding that an equation like 3/2*(8+2) does not equal 3/2(8+2), because they don't understand the basic rules of math.
Yeah, you're taking syntax to mean what it does in math, while i mean more of how words go together in ways that tell the same thing with different words...


And you obviously don't understand that 2(x) and 2*(x) being different from each other is the same thing as - and + are different, but there's nothing stopping the majority from declaring
that from now on + means the same as - in maths, and just finding another way to represent addition... they're just symbols in the end...

You can teach someone math just as correctly as you know it with 2(x) being the same as 2*(x) as long as you use something else for what you know as 2(x).

Thus the meaning you derive from those symbols isn't dependent on the symbols themselves, but what you've been taught to understand from them...
 

Joseph Webb

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The_AC said:
It's:
1. parentheses
2. exponents
3. multiplication/division
4. addition/subtraction

If there's a tie, go from left to right.
48/2(9+3) = (48/2)(9+3) =

48
--- x (9+3)
2

It isn't:
1. parentheses
2. exponents
3. multiplication/division (unless the division sign is written as a "/")
4. addition/subtraction
5. division where it's written as "/"

For now on, I'm assuming that anyone who disagrees is trolling.
I'm not trolling. The two is the coefficient of (9+3), meaning it technically is inside of the parentheses. Look up coefficients, you'll find a bunch of nonsense involving variables and stuff you won't understand. However, it won't matter, because I am not trolling. 2 is involved in the parentheses, therefore (9+3) is part of the denominator.
 

Joseph Webb

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mps4li3n said:
Joseph Webb said:
People are not understanding that an equation like 3/2*(8+2) does not equal 3/2(8+2), because they don't understand the basic rules of math.
Yeah, you're taking syntax to mean what it does in math, while i mean more of how words go together in ways that tell the same thing with different words...


And you obviously don't understand that 2(x) and 2*(x) being different from each other is the same thing as - and + are different, but there's nothing stopping the majority from declaring
that from now on + means the same as - in maths, and just finding another way to represent addition... they're just symbols in the end...

You can teach someone math just as correctly as you know it with 2(x) being the same as 2*(x) as long as you use something else for what you know as 2(x).

Thus the meaning you derive from those symbols isn't dependent on the symbols themselves, but what you've been taught to understand from them...
You don't get it. I've offered every example I can, but you don't understand it. You can phrase a mathematical equation any way you want, but if you write it correctly, it will still mean the same thing. 2 = 4/2 = 8/4 = 9(6+6)/9(3+3) = 2 You can get as complex as you want, it still means the same thing. The problem is that people aren't understanding the basis of math here. Coefficients are multiplicative factors, they always stay with their pairs. That's how math works. In the original equation, 2 is the coefficient of (9+3), meaning (9+3) will ALWAYS stay with the 2, meaning it will drop down into the denominator with it. The 2 wouldn't be (9+3)'s coefficient if there was a multiplication symbol between the two terms, because that's just how they work. Order of operations would kick in, and the answer would be 288.
 

Pyro Paul

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Taerdin said:
Pyro Paul said:
Here is the problem with that...
how does 48/2(9+3) become 48/2*(9+3)?

2(9+3) is NOT 2 * (9+3)
it is the simplified form of
((2*9)+(2*3))

by it your way you break the order of operations and Divide before you complete the Parentheses.
2(9 + 3) is equivalent to 2*(9+3)

2*9 + 2*3 = 18 + 6 = 24

2*(9+3) = 2*12 = 24

But that isn't the question.

The question is 48/2(9+3)

Which is evaluated as such

BEDMAS(or PEMDAS)

Brackets/Parentheses:

48/2(12)

Division & multiplication ( left to right)

24 * 12 = 288


Or if you prefer to distribute

48/2(9/3) = 48/2*9 + 48/2*3 = 288.
Honostly...

The confusing part in the above calculation is how "16 divided by 2[2] + 1" (in the line marked with the double-star) becomes "16 divided by 4 + 1", instead of "8 times by 2 + 1". That's because, even though multiplication and division are at the same level (so the left-to-right rule should apply), parentheses outrank division, so the first 2 goes with the [2], rather than with the "16 divided by". That is, multiplication that is indicated by placement against parentheses (or brackets, etc) is "stronger" than "regular" multiplication.

Source:
http://www.purplemath.com/modules/orderops2.htm
(bottem half of page)

The fact that you where NOT taught this in basic algebra and that i have to go to 'purplemath' to prove you wrong hurts my brain...

there is a complex reason involving distribution, coeffecents and terms that are probably beyond your comperhension as to WHY you calculate numbers against brackets First... but i'll leave it at just Basic Algebra level for you...
 

mps4li3n

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Joseph Webb said:
I'm not trolling. The two is the coefficient of (9+3), meaning it technically is inside of the parentheses. Look up coefficients, you'll find a bunch of nonsense involving variables and stuff you won't understand. However, it won't matter, because I am not trolling. 2 is involved in the parentheses, therefore (9+3) is part of the denominator.
And that's the thing, you take it as a coefficient while others do not... and if this was given to someone in 8th grade it would have to be (42/2)....

Context is always important, which is why, unless i'm very sure of the intentions of whoever gave it to me i'd always ask about it.

And as i said before, notation can and does differ based on country... saying that because that's the notation you use for that doesn't instantly mean it's what everyone uses... or even that whoever gave you the formula isn't using the lack of * wrong (like he could be asking how much money he would make in 48 days is he's working half a shift and the full shift gave him 9+3 $ per day).
 

Joseph Webb

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Pyro Paul said:
Taerdin said:
Pyro Paul said:
Here is the problem with that...
how does 48/2(9+3) become 48/2*(9+3)?

2(9+3) is NOT 2 * (9+3)
it is the simplified form of
((2*9)+(2*3))

by it your way you break the order of operations and Divide before you complete the Parentheses.
2(9 + 3) is equivalent to 2*(9+3)

2*9 + 2*3 = 18 + 6 = 24

2*(9+3) = 2*12 = 24

But that isn't the question.

The question is 48/2(9+3)

Which is evaluated as such

BEDMAS(or PEMDAS)

Brackets/Parentheses:

48/2(12)

Division & multiplication ( left to right)

24 * 12 = 288


Or if you prefer to distribute

48/2(9/3) = 48/2*9 + 48/2*3 = 288.
Honostly...

The confusing part in the above calculation is how "16 divided by 2[2] + 1" (in the line marked with the double-star) becomes "16 divided by 4 + 1", instead of "8 times by 2 + 1". That's because, even though multiplication and division are at the same level (so the left-to-right rule should apply), parentheses outrank division, so the first 2 goes with the [2], rather than with the "16 divided by". That is, multiplication that is indicated by placement against parentheses (or brackets, etc) is "stronger" than "regular" multiplication.

Source:
http://www.purplemath.com/modules/orderops2.htm
(bottem half of page)

The fact that you where NOT taught this in basic algebra and that i have to go to 'purplemath' to prove you wrong hurts my brain...
The worst part is that I've already directed them to that page, and they didn't believe me still.