48÷2(9+3)=?

[Morti]

I still think that the multiplication is implied.

So 2.

But not everyone subscribes to the principal of implied multiplication because it is not part of the standard order of operations:
terms inside parentheses or brackets
exponents and roots
multiplication and division
addition and subtraction

alot of people do though (which is why this verbal tug-o-war is happening), meaning that the correct answer is to tell the OP to "STFU, only noobs use "÷", pro's use brackets!".

 

[bliebblob]

Going over the knowyourmeme page again I think I found the heart of the problem:

It IS ambigious because it can be interpreted as

48
------ = 2
2(9+3)

or as

48
---- * (9+3) = 288
2

Neither is truly wrong because this:

x(a+b)

IMPLIES it is a single term but apparently it's not an actual rule. So now we know why our teachers at some point started to insist we use big divisionlines instead of "÷"

So yeah, that'll show me for getting into a forum argument. But hey, everyone won And it actually was a pretty fun brainexercise.

Now, anyone got a good idea for revenge on OP?

 

[dday4you]

Going over the knowyourmeme page again I think I found the heart of the problem:

It IS ambigious because it can be interpreted as

48
------ = 2
2(9+3)

or as

48
---- * (9+3) = 288
2

Neither is truly wrong because this:

x(a+b)

IMPLIES it is a single term but apparently it's not an actual rule. So now we know why our teachers at some point started to insist we use big divisionlines instead of "÷"

So yeah, that'll show me for getting into a forum argument. But hey, everyone won And it actually was a pretty fun brainexercise.

why revenge?

Now, anyone got a good idea for revenge on OP?

 

[Kenjitsuka]

It's 2, easy.

 

[Axolotl]

Well, you'd handle the division first.

Which would mean it's 24x12, so yes, 288.

Edit: Apparently I'm a complete idiot.

There is no correct answer. The whole BEDMAS or Order of Operations thing is primarily based on custom and is taught differently in different parts of the world. The question uses that to be ambiguous, it is not a "real" mathematical question so much as hook to try and start semantical arguements based on pointless mathematical principles that nobody above the age of 12 should be bothering with.

TLR It's a troll thread.

you know a computer actually uses these operations in a uniform fashion right? and without that uniformity, you wouldn't be able to write that message.

A computer will yes. Two seperate computers may calculate them differently however. For example I personally have two calculators of different models (for refrence a CASIO fx-83GT PLUS and a CASIO fx-83ES) they give me different answers, one says 2 the other 288. This is because they've been made by different people who were taught different methods of order of operations because there are no uniformly agreed set of rules for order of operations. This is because it is not real mathematics, it is a crutch for people who do not understand how the write mathematical questions.

 

[theklng]

Well, you'd handle the division first.

Which would mean it's 24x12, so yes, 288.

Edit: Apparently I'm a complete idiot.

There is no correct answer. The whole BEDMAS or Order of Operations thing is primarily based on custom and is taught differently in different parts of the world. The question uses that to be ambiguous, it is not a "real" mathematical question so much as hook to try and start semantical arguements based on pointless mathematical principles that nobody above the age of 12 should be bothering with.

TLR It's a troll thread.

you know a computer actually uses these operations in a uniform fashion right? and without that uniformity, you wouldn't be able to write that message.

A computer will yes. Two seperate computers may calculate them differently however. For example I personally have two calculators of different models (for refrence a CASIO fx-83GT PLUS and a CASIO fx-83ES) they give me different answers, one says 2 the other 288. This is because they've been made by different people who were taught different methods of order of operations because there are no uniformly agreed set of rules for order of operations. This is because it is not real mathematics, it is a crutch for people who do not understand how the write mathematical questions.

http://en.wikipedia.org/wiki/Reverse_Polish_notation

we're talking computers here son, not some cheapskate calculators. reverse polish notation is used in every stack based machine, which includes pretty much every cpu over the past 20 years. this ensures uniformity.

 

[TiefBlau]

you're wrong. you release brackets first, so it would be 48/(18+6)

Oh dear. I don't think "release brackets" means what you think it means.

You operate on the brackets, meaning, whatever's inside the brackets is calculated first.

Hence, you first calculate (9+3) to be 12. Then it's multiplication/division, so you go left to right.

You don't distribute the 2. That's not even what the "brackets" operation is. Distribution is multiplication, which is interchangeable with division, so even if you wanted to do it that way, it'd be like this:

48 / 2 * (9+3)
24 * (9+3)
216 + 72
288

your other example is faulty logic, 48 - 2 + 12 = 48 + 10 = 58 (incidentally, (48 - 2) + 12 = 46 + 12 = 58).

You still don't get it...

you're talking to a programmer here, i've been doing math for longer than you've lived. i do these equations pretty much every day, why else would i link the goddamn system that makes everything uniform?

Holy shit, I didn't know I was talking to a programmer. Allow me to alter the foundations of basic arithmetic to accommodate someone of your incredible stature.

You're also going to need to contact Sun Microsystems on their serious error in judgment, because in Java, 48 / 2 * (9+3) still equals 288. I'd hate to think of the catastrophic failures that might have stemmed from this oversight.

And while I'd hate to think of the kind of math you've been doing, I'm actually kind of curious to see the kind of person (assuming you have done mathematics for longer than I've lived) that can breeze by differential equations and discrete mathematics without a basic grasp of arithmetic and the order of operations. I can't imagine you could possibly acquire a firm understanding of the chain rule if you didn't know what goes inside or outside brackets, so please, enlighten a scrub like myself.

 

[theklng]

you're wrong. you release brackets first, so it would be 48/(18+6)

Oh dear. I don't think "release brackets" means what you think it means.

You operate on the brackets, meaning, whatever's inside the brackets is calculated first.

Hence, you first calculate (9+3) to be 12. Then it's multiplication/division, so you go left to right.

You don't distribute the 2. That's not even what the "brackets" operation is. Distribution is multiplication, which is interchangeable with division, so even if you wanted to do it that way, it'd be like this:

48 / 2 * (9+3)
24 * (9+3)
216 + 72
288

your other example is faulty logic, 48 - 2 + 12 = 48 + 10 = 58 (incidentally, (48 - 2) + 12 = 46 + 12 = 58).

You still don't get it...

you're talking to a programmer here, i've been doing math for longer than you've lived. i do these equations pretty much every day, why else would i link the goddamn system that makes everything uniform?

Holy shit, I didn't know I was talking to a programmer. Allow me to alter the foundations of basic arithmetic to accommodate someone of your incredible stature.

You're also going to need to contact Sun Microsystems on their serious error in judgment, because in Java, 48 / 2 * (9+3) still equals 288. I'd hate to think of the catastrophic failures that might have stemmed from this oversight.

And while I'd hate to think of the kind of math you've been doing, I'm actually kind of curious to see the kind of person (assuming you have done mathematics for longer than I've lived) that can breeze by differential equations and discrete mathematics without a basic grasp of arithmetic and the order of operations. I can't imagine you could possibly acquire a firm understanding of the chain rule if you didn't know what goes inside or outside brackets, so please, enlighten a scrub like myself.

this equation has already been resolved as ambiguous. i took the liberty of finding the a source related to this, explaining why it has been deemed as ambiguous:

I?m a math professor, and my view is that although the standard convention, if applied precisely and rigorously, does give an unambiguous procedure to follow, nobody, and that includes professional mathematicians, would ever write a formula like this. This is mostly because, after about 3rd grade, none of us ever use the division symbol ever again.

from: http://www.reddit.com/r/WTF/comments/gyrmq/6212_reaaaaally/

or in the case you don't believe that, here's a comparison between the two:

http://www.youtube.com/watch?v=gFKGbU6ARQg

and

http://www.wolframalpha.com/input/?i=48%C3%B72%289%2B3%29

oh and: obviously even if i did do arithmetic errors in my code, it'd be fixed way before any sort of release due to this thing called testing. and even if an arithmetic fault would slip through that,given that i'm not in the medicinal or third party medicinal business, what i do isn't exactly living up to your hyperbole.

 

[luke10123]

BODMAS
brackets of divide multiply add subtract.
that's maths for a ten year old
(answer's 2 obviously)

I'm kinda sick of the people who come into this thread thinking it's simple maths and boasting about dumb we are while completely missing the point of the thread because I can only assume they didn't bother to read it.

1) It really IS simple maths.
2) missing the point of the thread am I? "is it 2 or 288?" I really don't see how...
3) I believe you meant to say 'about HOW dumb we are'. Believe that shows it didn't need saying...

 

[cookyy2k]

must not be a scientific Calculator, normal ones are not programed to prioritise brackets

Most calculators also say sqrt(-1) is syntax error and that ain't right. those things need to be used as a tool not trusted completly. Also different calculators say different results for this since it's ambiquous.

My calculator is a Casio fx-82AU and it clearly says "Scientific Calculator" on the front. They're given out by our school for use from years 8-12 and are approved by the Board of Studies to use in all exams. Trust me when I say that this calculator is the correct one to work an equation out with.

Besides, I showed you how I did it on paper with the working so the calculator is irrelevant.

Doesn't really matter what type your calculator is. Different calculators give different results for the problem... Also type root(-1) in, syntax error is not the answer, calculators are wrong in certain instances, hell take a calculator as advanced as you want and you have a computer and even they can give wrong answers in certain instances. A calculator is a nice tool to help with such things but really you should never rely on one completly.

edit: my scientific, every day use calc gives 288. My graphical, bust out for trickier stuff gives 2.

 

[DaMullet]

No. You are completely missing the point of what everyone is saying. Even if you ignore the different rules for variables and constants, your maths is incorrect. Let's look at the first line:

48/2(9+x)=2

What you have done is distributed the 2 into the brackets. THIS IS INCORRECT. As this is multiplication, and not "part of the brackets", you have to do division and multiplication from left to right, as they have equal precedence. So rather than:

48/(18+2x)=2

you should have:

24(9+x)=2
216+24x = 2
24x = -214
x = -8.917

Which is not 3, obviously.

Despite your algebraic method, you are still falling for the trap that so many others are falling for, which is to assume that the 2 is part of the brackets, which is WRONG. Algebra does not make your answer more valid, especially when the core idea of the method, which happens to be what people have been trying to tell you is wrong, is completely overlooked.

So... let's do it your way then

48/2(9+x)=288
24(9+x)=288
216+24x=288
24x=72
x=3

........... UH...............

Interesting. No wonder this is a debate.

Alright, so what's the difference between 2(1+1) and 2*(1+1)?

and if they're not, why write it like that? Cause now I'm curious

 

[cookyy2k]

Interesting. No wonder this is a debate.

Alright, so what's the difference between 2(1+1) and 2*(1+1)?

and if they're not, why write it like that? Cause now I'm curious

2(1+1)=2*(1+1)... when missed out the multiplication is implied. It all depends on if you really feel the need to explicitly state multiplication or not.


EDIT:

The answer is either.... it's implicit. it depends how you interpret the question when it's condenced to one line.

Some read

24
------
2(9+3)​

While others read

24
---- (9+3)
2​

And you know what... it's ambiguous which you interpret that one line of text to be. It's an implied relation which people can read 2 ways. This would have to be made explicit which before one answer could be chosen. As it stand it can be EITHER.

 

[DaMullet]

Interesting. No wonder this is a debate.

Alright, so what's the difference between 2(1+1) and 2*(1+1)?

and if they're not, why write it like that? Cause now I'm curious

2(1+1)=2*(1+1)... when missed out the multiplication is implied. It all depends on if you really feel the need to explicitly state multiplication or not.


EDIT:

The answer is either.... it's implicit. it depends how you interpret the question when it's condenced to one line.

Some read 24
------
2(9+3)

While others read 24
---- (9+3)
2

And you know what... it's ambiguous which you interpret that one line of text to be. It's an implied relation which people can read 2 ways. This would have to be made explicit which before one answer could be chosen. As it stand it can be EITHER.

Hmm... okay.

So, how do you work out x/2(9+3)=288 and 48/x(9+3)=288?

 

[cookyy2k]

So, how do you work out x/2(9+3)=288 and 48/x(9+3)=288?

Again these are implicit statements due to one line condencement.

Is it x/(2(9+3)) or (x/2)(9+3)? the brackets are required to make these explicit statements.

 

[DaMullet]

So, how do you work out x/2(9+3)=288 and 48/x(9+3)=288?

Again these are implicit statements due to one line condencement.

Is it x/(2(9+3)) or (x/2)(9+3)? the brackets are required to make these explicit statements.

Why? Why isn't x treated just like a number? How is replacing a number with X suddenly break the whole thing?

 

[cookyy2k]

So, how do you work out x/2(9+3)=288 and 48/x(9+3)=288?

Again these are implicit statements due to one line condencement.

Is it x/(2(9+3)) or (x/2)(9+3)? the brackets are required to make these explicit statements.

Why? Why isn't x treated just like a number? How is replacing a number with X suddenly break the whole thing?

They were broken before... 24/2(9+3) is not a complete expression, it's not explicit. It could be written 24/(2(9+3)) or (24/2)(9+3) without loss of generality however these two expressions have different results.

 

[DaMullet]

So, how do you work out x/2(9+3)=288 and 48/x(9+3)=288?

Again these are implicit statements due to one line condencement.

Is it x/(2(9+3)) or (x/2)(9+3)? the brackets are required to make these explicit statements.

Why? Why isn't x treated just like a number? How is replacing a number with X suddenly break the whole thing?

They were broken before... 24/2(9+3) is not a complete expression, it's not explicit. It could be written 24/(2(9+3)) or (24/2)(9+3) without loss of generality however these two expressions have different results.

Now, you've really lost me. How is 24/2*(9+3)=288 not a valid equation?

 

[cookyy2k]

Now, you've really lost me. How is 24/2*(9+3)=288 not a valid equation?

The problem lies in the way the expression is written, it doesn't imply only one fexpression but 2 different ones as I've said earlier. I can solve 24/x(9+3)=288 2 ways...

48/x(9+3)=288
48/288=x(9+3)
48/(288(9+3))=x
x=4/288


OR

48/x(9+3)=288
48/x=288/(9+3)
x/48=12/288
x=(48*12)/288
x=2

Either is equally valid. 1st is 48/(x(9+3)), 2nd is (48/x)(9+3)=288

EDIT... just realised I keep using 24 instead of 48! Above change to rectify this...

 

[DaMullet]

Now, you've really lost me. How is 24/2*(9+3)=288 not a valid equation?

The problem lies in the way the expression is written, it doesn't imply only one fexpression but 2 different ones as I've said earlier. I can solve 24/x(9+3)=288 2 ways...

48/x(9+3)=288
48/288=x(9+3)
48/(288(9+3))=x
x=4/288


OR

48/x(9+3)=288
48/x=288/(9+3)
x/48=12/288
x=(48*12)/288
x=2

Either is equally valid. 1st is 48/(x(9+3)), 2nd is (48/x)(9+3)=288

EDIT... just realised I keep using 24 instead of 48! Above change to rectify this...

But no, I dissagree, they can't both be valid because they give different answers.
The beautiful thing about math is 1=1.

My way

48/x(9+3)=288
48/12x=288
48=3456x
x=0.0138888888888889

or

48/x(9+3)=2
48/12x=2
48=24x
x=2

Now

x/2(9+3)=2
x/24=2
x=48

See, here's my problem. I do it my way, or the way I was taught at least, and I keep getting the right answer no matter what I do. You're way can be done inncorrectly which strikes me as REALLY strange.

My way, I don't have to add brackets anywhere, at all, and the answer still works and there is only one solution; 48/2(9+3) = 2.

What's the point in BEDMAS if you have to add brackets to make algebra work?

EDIT

Wait a minute... how can you change 24 to 48 in the same equation and get the same answer???? WTF?

 

[cookyy2k]

Now, you've really lost me. How is 24/2*(9+3)=288 not a valid equation?

The problem lies in the way the expression is written, it doesn't imply only one fexpression but 2 different ones as I've said earlier. I can solve 24/x(9+3)=288 2 ways...

48/x(9+3)=288
48/288=x(9+3)
48/(288(9+3))=x
x=4/288


OR

48/x(9+3)=288
48/x=288/(9+3)
x/48=12/288
x=(48*12)/288
x=2

Either is equally valid. 1st is 48/(x(9+3)), 2nd is (48/x)(9+3)=288

EDIT... just realised I keep using 24 instead of 48! Above change to rectify this...

But no, I dissagree, they can't both be valid because they give different answers.
The beautiful thing about math is 1=1.

My way

48/x(9+3)=288
48/12x=288
48=3456x
x=0.0138888888888889

or

48/x(9+3)=2
48/12x=2
48=24x
x=2

Now

x/2(9+3)=2
x/24=2
x=48

See, here's my problem. I do it my way, or the way I was taught at least, and I keep getting the right answer no matter what I do. You're way can be done inncorrectly which strikes me as REALLY strange.

My way, I don't have to add brackets anywhere, at all, and the answer still works and there is only one solution; 48/2(9+3) = 2.

What's the point in BEDMAS if you have to add brackets to make algebra work?

I'm adding brackets to remove the ambiguity in this. the problem being in one line computer text I can't write it out fully so i'm using brackets to show which on the earlier examples I made I'm using. The thing is both my ways are mathematically valid.

x/2(9+3)=2
x/2=2/(9+3)
x=4/12

nothing mathematically wrong with what I just did, it's all to do with how the expresion is written.