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einsteinboricua
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 4:49 am

Quoting Maverick623 (Reply 98):
Why are Google and Excel changing the order of operations because of a implied value?

Because Excel considers the "-" sign to be -1*(whatever), which is true. The negative sign is only an indication that a -1 is multiplying the argument. Which is why I can't stress the use of parenthesis enough. In written language (the one where we write using a pen or pencil on paper), the equation being solved can be written in ways that can satisfy both answers.

However, when written in a machine, parenthesis are needed to determine what's a denominator and what isn't. Programmers know this, which is why I, along with Excel and even Java, say the answer is 288.
For the umpteenth time, if your answer is 2, then it can only be achieved if the denominator of the division is 2(9+3), which in terms of machine language is written as 48/(2*(9+3)) where the bold parenthesis indicates that this entire operation is to be the denominator of the fraction.

By leaving the parenthesis limited to 9+3, you run into the little trouble of finding that the sum will go first but the 2 outside it will be interpreted as a multiplication. What you will find is 48/2*12 --------> 24*12 ----------> 288.
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CXfirst
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 5:31 am

Solve for x:

48÷x(9+3) = 288

Please answer this.

-CXfirst
 
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einsteinboricua
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 5:39 am

Quoting CXfirst (Reply 101):
48÷x(9+3) = 288

48/x*(9+3)=288
48/x=288/12
48/x=24
1/x=24/48
1/x=1/2

Inverse

x=2

alternatively:

48/x=24
x=48/24

x=2

[Edited 2011-04-13 22:40:46]
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Mir
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 5:42 am

Quoting CXfirst (Reply 101):
48÷x(9+3) = 288

Please answer this.

x=.0139 (rounded)

-Mir
7 billion, one nation, imagination...it's a beautiful day
 
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einsteinboricua
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 5:46 am

Which of these two do you mean:

a) (48/x)*(9+3)=288
b) 48/(x(9+3))=288

They are not the same. The way you wrote it is interpreted as option a.
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Flighty
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 5:48 am

Quoting einsteinboricua (Reply 104):
The way you wrote it is interpreted as option a.

There is no interpretation necessary. (a) is what was asked and (b) is some other equation.
 
B737200
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 5:55 am

I forgot how annoying these things can be...

I have a simple solution, I use a lot of brackets when writing out equations. This way you are just asking for someone to misinterpret, the brackets help prevent this. Anyway since about 7 years back into my studies I've rarely seen any equation written down using the ÷ sign, probably for this very reason.

As for my answer I would have said 2.

[Edited 2011-04-13 23:00:52]
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Quokka
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 6:00 am

The answer surely depends on whether you are buying or seeking a refund. If you are buying the price is 288, if you want a refund you get 2. Simple once you know how.  
 
vikkyvik
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 6:01 am

Quoting unattendedbag (Reply 93):
what's the point of living?

the answer is 2


Um, no, the answer to "what's the point of living?" is 42.

Which is, therefore, also the answer to 48/2(9+3).
I'm watching Jeopardy. The category is worst Madonna songs. "This one from 1987 is terrible".
 
KingFriday013
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 6:23 am

Quoting vikkyvik (Reply 108):
Which is, therefore, also the answer to 48/2(9+3).


 scared 

NO!!!!!   

48/2(9+3) is NOT equal or equivalent to life, the universe, etc. Therefore, the answer is 288 (yes, I've changed my stance from my original reply).

-J.

[Edited 2011-04-13 23:24:23]
Will add later
 
Maverick623
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 6:35 am

Quoting einsteinboricua (Reply 100):
Because Excel considers the "-" sign to be -1*(whatever), which is true.

No, it doesn't. If you change the - to -1 (or -1*), you get two different answers.

Click on my links. See for yourself:

Quoting Maverick623 (Reply 98):
If -(9+3) and -1(9+3) are the same thing (which they are), why two different answers?
Quoting vikkyvik (Reply 108):


Um, no, the answer to "what's the point of living?" is 42.

Um, no, that's the answer to The Ultimate Question of Life, The Universe, And Everything. We don't know the question.  
"PHX is Phoenix, PDX is the other city" -777Way
 
vikkyvik
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 6:52 am

Quoting Maverick623 (Reply 110):

Um, no, that's the answer to The Ultimate Question of Life, The Universe, And Everything. We don't know the question.

I'm aware, but I think "what's the point of living?" is close enough!

Who knows, maybe 48/2(9+3) is the ultimate question.

Or perhaps it's "what do you get when you multiply 6 by 9..."

 
I'm watching Jeopardy. The category is worst Madonna songs. "This one from 1987 is terrible".
 
Mir
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 7:18 am

Quoting vikkyvik (Reply 111):
Or perhaps it's "what do you get when you multiply 6 by 9..."

Doubtful, since that's 54.

-Mir
7 billion, one nation, imagination...it's a beautiful day
 
vikkyvik
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 7:46 am

Quoting Mir (Reply 112):
Quoting vikkyvik (Reply 111):
Or perhaps it's "what do you get when you multiply 6 by 9..."

Doubtful, since that's 54.

'Twas a line from The Restaurant at the End of the Universe from the Hitchhiker's Guide series  
I'm watching Jeopardy. The category is worst Madonna songs. "This one from 1987 is terrible".
 
dragon6172
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 10:01 am

Quoting CXfirst (Reply 91):
If it gives any consolation. My graphics calculator says 2, and it should operate using order of operations (meaning it sees 2[9+3] as part of the parenthesis)

No consolation at all, my graphing calculator says 288.
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EA CO AS
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 11:35 am

This thread has reminded me that to this day, there are two phrases that still send shivers down my spine:

"Solve for X" and "show your work."

Eff that.
"In this present crisis, government is not the solution to our problem - government IS the problem." - Ronald Reagan

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offloaded
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 11:55 am

BODMAS. No idea why I remember that from school but brackets, division, multiplication, addition, subtraction.

48 ÷ 2(9+3)=

48 ÷ 2(12) ... (still have brackets so they have to go first)

48 ÷ 24

2.
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ojas
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 12:12 pm

Quoting atrude777 (Reply 15):
I got 288.

You always go from Left to Right in order of what comes up first.

[quote=einsteinboricua,reply=17]The answer is 288. Order of operation: parenthesis, exponents, and from left to right multiplication and division, and then from left to right again addition and subtraction.[/quote

That is correct.

In solving such expressions just the rule of BODMAS (here in India we call it that)

B = Bracket
O = Order
D = Division
M = Multiplication
A = Addition
S = Subtraction

and by that logic

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

288 is the right answer, whoever has got 2 the answer is wrong.
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casinterest
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 12:55 pm

Quoting ojas (Reply 117):

288 is the right answer, whoever has got 2 the answer is wrong.

NO NO NO  

The Distributive property of Math is in full play here.

a(b+c) =ab+ac

The fact that there is another symbol proceding the 2 seperates the 48 from being part of the intial solve.

There is an implicit Parenthesis invoked when you write an equation of the form a(x+z) surrounding the whole equation thus making it of the form
(ax+az) . Has the 48 been part of the implied distributive formula, the original equation would have been written in the form (48/2)(9+3)

With the form originally given, you have to apply the distributive formula first so 2(9+3) becomes 24 and 48/24 is 2


Most calculators and programming lanquages get a different answer because they have specific orders of operation that do not include algebra as part of their programming. .
Where ever you go, there you are.
 
offloaded
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 12:56 pm

Quoting ojas (Reply 117):
48 / 2(9+3) = 48/2*12

Are you sure? I mean you aren't clearing your brackets completely first. Don't you have to complete everything to do with brackets and then move on? What I'm getting at is you changed 48 ÷ 2(12) to 48 ÷ 2*12 which is then 48 ÷ 2 x 12 with is 288.   
To no one will we sell, or deny, or delay, right or justice - Magna Carta, 1215
 
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fxramper
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 1:19 pm

Quoting UAL747 (Reply 21):
Please
Excuse
My
Dear
Aunt
Sally

This is also how I learned it in grade school.   
 
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yowza
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 2:13 pm

Perhaps I'm being REALLY thick here but what's all the confusion about? Is the answer not 2?
 
offloaded
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 2:18 pm

Quoting yowza (Reply 121):

Well I think it is, but others disagree.
To no one will we sell, or deny, or delay, right or justice - Magna Carta, 1215
 
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einsteinboricua
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 2:40 pm

Quoting offloaded (Reply 119):
I mean you aren't clearing your brackets completely first

Yes it is. Because of you had 3(2+1), once you solve what't inside the parenthesis, you're left with 3(3)=3*3...it's a multiplication.

People also interpret the mnemonic PEMDAS wrong since they assume that multiplication has higher priority than division, and the same goes with addition and subtraction. Parenthesis hold while there are OPERATIONS INSIDE it. Once you are left with a number, there's a multiplication.

So while P goes before E, M & D have the same priority and then A & S have the same priority afterwards. How to determine which one to do?

---------------------------------------------->

[Edited 2011-04-14 07:41:48]
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cgnnrw
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 3:19 pm

PEMDAS

My math teacher taught us this:
Please
EXHUME
My
DEAD
Aunt
Sally

He was weird.....also he played a lot of "pocket pool".
A330 man.
 
andz
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 3:41 pm

Quoting Longhornmaniac (Reply 9):
For the record, I also got 288, but there are a lot of people, including some very smart ones, who believe the answer is 2.

I didn't read the whole thread but I got 2 in about the same number of seconds.
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ManuCH
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 5:05 pm

Quoting NZ107 (Reply 82):
For me, it is 2. If there was a multiplication symbol in between the 2 and the brackets, it'd change the whole equation to give 288. But it is ambiguous.

The calculator I use on my Mac, iota-calc, thinks so as well.

If I enter 48/2*(9+3) it says 288.
If I enter 48/2(9+3) it says 2.

So there seems to be a difference if there's a multiplication sign before the brackets or not.
Never trust a statistic you didn't fake yourself
 
andz
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 5:27 pm

Quoting ManuCH (Reply 126):
So there seems to be a difference if there's a multiplication sign before the brackets or not.

As I remember maths in the distant mists of time, 2(9+3) implies that 2 is multiplied by the content of the brackets.
After Monday and Tuesday even the calendar says WTF...
 
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northstardc4m
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 5:44 pm

Quoting ManuCH (Reply 126):
So there seems to be a difference if there's a multiplication sign before the brackets or not.

2(9+3) is the same as writing the expression 2x where x is 9+3
that makes the operation total for the brackets 24 if we are going this way

Again though, this isn't written properly...

It should be either 48÷2*(9+3) OR 48÷(2*(9+3)) OR 48÷(2x) where x=9+3=12 under the rules i was taught in the BEDMAS system.

48÷2(9+3) is shorted a function.
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SAA380
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 5:56 pm

The correct answer is indeed 2.

The original equation is 48/2(9+3).

The people getting 288 are doing the following:

48/2 *12 .... which is mathematically incorrect since you are now multiplying 12 with the numerator (read 12/1) not the denominator as the equation originally states. The correct way to write it in a form simmilar to that is 48/2 * 1/12 (Since you are now multiplying the 12 with the denominator s originally stated.)

The answer can thus be none other than 2.
(Wrote engineering calculus test Wednesday)

SAA380   
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Maverick623
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 6:16 pm

Quoting ojas (Reply 117):
and by that logic

I refer you to the GIGO concept (Garbage In, Garbage Out) because, again:

Quoting ojas (Reply 117):
2(9+3)
Quoting ojas (Reply 117):
2*12

These are not the same function!

48/2(9+3) = x

Using the distributive property (since you can distribute before anything else, due to it being a known equality already... again, basic 8th grade math. a(b+c) = (ab) + (ac) ). You also cannot imply a parenthesis around the 48/2. It MUST be provided

48/(18+6)

48/24

2

Quoting yowza (Reply 121):
but what's all the confusion about?

People ignoring the distributive property of parenthetical operations.
"PHX is Phoenix, PDX is the other city" -777Way
 
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einsteinboricua
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 6:18 pm

Quoting Northstardc4m (Reply 128):
It should be either 48÷2*(9+3) OR 48÷(2*(9+3)) OR 48÷(2x) where x=9+3=12 under the rules i was taught in the BEDMAS system.

   THANK YOU!!!

Quoting SAA380 (Reply 129):
which is mathematically incorrect since you are now multiplying 12 with the numerator (read 12/1) not the denominator as the equation originally states.

The equation says 48/2(9+3). Under the PEMDAS rules, parethesis is done first.
48/2(12)

If you wish for 48 to be divided completely by 2(12), encapsulate it inside parenthesis again so that the multiplication inside it is done first. If you don't, then since multiplication and division have the same priority, you start from left to right. There's a division first, so 48/2=24

Finally that division (24) is multiplied by 12.

PEMDAS fails to consider that you go from left to right.

This image, posted above should clear thing up on why some people get 2 and others 288.



The correct way of writing the option below would be 48/(2(9+3)). In the meantime, 48/2 is a division followed by the multiplication of 2(9+3) (the above option).
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casinterest
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 6:34 pm

Quoting einsteinboricua (Reply 131):
This image, posted above should clear thing up on why some people get 2 and others 288.

This image is making a leap of assuming a multiplication and changing the operation from a distribution rule considered under algebraic rules.


The way the formula is written, the distribution rule must be applied first.
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einsteinboricua
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 6:39 pm

Quoting casinterest (Reply 132):
The way the formula is written, the distribution rule must be applied first.

Distribution is nothing more than multiplication. ERGO, it does NOT have to go first.
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casinterest
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 6:50 pm

Quoting einsteinboricua (Reply 133):
Distribution is nothing more than multiplication. ERGO, it does NOT have to go first.

Yes it does, the distributive property is written as x(a+b) not (z /x)(a+b)
The distributive property to hold true has to be executed first and foremost.

[Edited 2011-04-14 12:11:40]
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zak
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 7:49 pm

yesterday wolfram alpha reported 288 as result. today they corrected it to 2.
nuff said
10=2
 
Flighty
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 7:50 pm

Quoting casinterest (Reply 118):
Most calculators and programming lanquages get a different answer because they have specific orders of operation that do not include algebra as part of their programming. .

Sorry. You are wrong. PEMDAS is not necessarily correct.

P.....E.........MD.................AS.

Multiplication or Division
Addition or Subtraction
These are done in order of appearance, from left to right.

This is a worldwide standard and is not negotiable.

Quoting SAA380 (Reply 129):
The correct answer is indeed 2.

No, that is not the answer. Instead, you are solving this equation:

48/(2(9+3)).

That is a new equation that you made up.

The original equation: 48/2(9+3)

The operations are done from left to right. You are doing it backwards. Division and Multiplication are done TOGETHER from left to right unless parentheses override the order. Which here they do not!

Mathematica says it is 288. That is the correct answer period.

Quoting ojas (Reply 117):
288 is the right answer, whoever has got 2 the answer is wrong.

           
 
zak
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 7:54 pm

Quoting ojas (Reply 117):
288 is the right answer, whoever has got 2 the answer is wrong.

i filed a bug report with wolfram software today, the guys who make mathematica. they gave 288 as result aswell, they corrected the error, whats up with you 288 ppl
10=2
 
Maverick623
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 8:26 pm

Quoting einsteinboricua (Reply 133):
Distribution is nothing more than multiplication.

Absolutely false.

x(y+z) = (xy)+(xz).

Since there are no parentheses to denote the 48/2 as a separate expression, you are required to distribute the expression 2(9+3), as is. Also note the lack of the multiplication symbol, which further implies that it's not merely a simple multiplication of terms.

Also, your graphic has a trollface for a reason. You do not tell someone how to "read" an equation that's presented in an ambiguous way. The first line (titled "How you should read it") implies parentheses around the 48/2, which simply do not exist in the equation. Likewise, the second line ("How you are reading it") implies parentheses around the 2(9+3) which also do not exist.

Quoting Flighty (Reply 136):
Mathematica says it is 288. That is the correct answer period.

So instead of actually knowing the rules of math, you use buggy software, assuming that it's right and everyone else is wrong?

Again, look up Garbage In, Garbage Out.
"PHX is Phoenix, PDX is the other city" -777Way
 
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northstardc4m
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 8:33 pm

I have come to the conclusion... that this whole thing is wrong.

The correct answer is 42

That is all...

Ok seriously, the argument is going on well outside this forum, with professors, physicists, math historians and all manner of uppity-up-thinky-people disagreeing.

Basically, is it:

48/2*(9+3)=288
or
48/(2*(9+3))=2

all depends on your interpretation and without something between 2 and ( in the base equation, neither and both are correct. And amazingly enough i cannot find ANY rule about juxtaposition operations and brackets. consensus is multiply but consensus on part of bracket or not part of bracket is another story and probably will be debated until we all die of old age... and our descendants will go to war over it I'm sure!

So can we seriously agree to disagree already?
Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety.
 
Flighty
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 8:34 pm

Quoting Maverick623 (Reply 138):
So instead of actually knowing the rules of math, you use buggy software, assuming that it's right and everyone else is wrong?

I know the rules rather well, and so does Wolfram. This is really not taxing my abilities, or theirs.

Quoting zak (Reply 137):
i filed a bug report with wolfram software today, the guys who make mathematica. they gave 288 as result aswell, they corrected the error, whats up with you 288 ppl

So, you made a bug report. Did you change the rules of math? No
 
GAIsweetGAI
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 8:34 pm

Quoting Maverick623 (Reply 138):
Garbage In, Garbage Out.

  

The operation is simply badly written. Apart from being trollishly amusing, it's pretty much useless.
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XaraB
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 8:35 pm

Sorry, 288 people.

Quoting casinterest (Reply 118):
The Distributive property of Math is in full play here.

a(b+c) =ab+ac

The fact that there is another symbol proceding the 2 seperates the 48 from being part of the intial solve.

There is an implicit Parenthesis invoked when you write an equation of the form a(x+z) surrounding the whole equation thus making it of the form
(ax+az) . Has the 48 been part of the implied distributive formula, the original equation would have been written in the form (48/2)(9+3)

With the form originally given, you have to apply the distributive formula first so 2(9+3) becomes 24 and 48/24 is 2


Most calculators and programming lanquages get a different answer because they have specific orders of operation that do not include algebra as part of their programming. .

This is the correct way of thinking. Any mathematical software and calculators are prone to errors in "corner situations" like this one, because of simplified code and approximations. Any calculator capable of doing integrals is only doing numerical *approximations*, and do NOT present the absolutely correct answer. In order to do that, you have to follow mathematical rules and work by hand. This particular problem is no different. Follow the rule provided by Casinterest when calculating by hand, and 2 is the only possible answer. No childish nursing rhymes needed  

I have had several advanced theoretical mathematics courses during my education, which I'm finishing these days. This is the only way to do it...
An open mind is not an empty one
 
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northstardc4m
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 8:39 pm

oh and interestingly, when i run this in Excel =sum(48/2(6+3))
It pops and error asking me to accept =sum(48/2*(6+3))
At least Excel admits the formula is invalid...

[Edited 2011-04-14 13:51:18]
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Maverick623
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 8:40 pm

Quoting XaraB (Reply 142):
Sorry, 288 people.

For a second, I thought you meant "Sorry, the answer is 288, people". Confusion rivaled only by the original equation.
"PHX is Phoenix, PDX is the other city" -777Way
 
Flighty
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RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 8:58 pm

Quoting XaraB (Reply 142):
ny mathematical software and calculators are prone to errors in "corner situations" like this one, because of simplified code and approximations.

So it's your opinion that Mathematica... version 8... can't multiply a few real numbers together. Oooookay.

Here's Mathematica 7's comment

In[2]:= 48/2 (9 + 3)


Out[2]= 288

This has nothing to do with theory. Why not fire up MATLAB.


>> 48/2*(9+3)

ans =

288

Oh gee. Looks like we need another "bug report"  


Okay. Now how about SAS.

data a_net;
answer = 48/2*(9+3);
run;
proc print data=a_net;
run;

Obs answer

1 288


How about the R statistical suite?

> 48/2*(9+3)
[1] 288
>


If there is any possible objection, it would be that I specified a * between the 2 and the (. This is clearly implicit, and I think everyone agrees with that.
 
Mir
Posts: 19491
Joined: Mon Jan 05, 2004 3:55 am

RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 9:07 pm

Quoting Flighty (Reply 145):
If there is any possible objection, it would be that I specified a * between the 2 and the (. This is clearly implicit, and I think everyone agrees with that.

The whole argument has been whether that multiplication symbol is implied or not, so no, it's not clearly implicit.

-Mir
7 billion, one nation, imagination...it's a beautiful day
 
Maverick623
Posts: 4722
Joined: Thu Nov 30, 2006 9:13 am

RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 9:19 pm

Quoting Flighty (Reply 145):

So it's your opinion that Mathematica... version 8... can't multiply a few real numbers together.

Oh for the love of ....

The distributive property involves multiplication, but multiplication it is not.

You would need parenthesis around the 48/2 in order to distinguish that as a phrase separate from the (9+3).

And, please, guys:

Quoting Flighty (Reply 145):
*

Does not exist in the original equation, so stop putting it in there.

And Flighty, maybe you missed the part where he does this stuff for a living. I'd take his word over a GIGO formula anyday.
"PHX is Phoenix, PDX is the other city" -777Way
 
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einsteinboricua
Posts: 8251
Joined: Thu Apr 15, 2010 4:11 pm

RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 9:31 pm

Quoting casinterest (Reply 134):
Yes it does, the distributive property is written as x(a+b) not (z /x)(a+b)
The distributive property to hold true has to be executed first and foremost.

Distributive is not among the order of operations. If you want the distribution to go first for the (what time is it now?) time, put parenthesis around it. Otherwise, you have a multiplication in your hands.

Quoting Mir (Reply 146):
The whole argument has been whether that multiplication symbol is implied or not, so no, it's not clearly implicit.

Well, many, if not all math programs, have said that there is a multiplication in it since they all give out 288.

Quoting Flighty (Reply 145):

Let's try Java:
double x=48/2(9+3) (for which Java complains and asks that you put a '*' between the 2 and ( )
System.out.println(+x);

Answer: 288.

However, if I enter:
double x=48/(2(9+3)) (for which Java once again complains to put the asterisk)
System.out.println(+x)

Answer: 2

How about Excel:
=48/2(9+3) (Excel claims there's an error and offers to correct it by placing an asterisk between the 2 and (.

Cell A1 will have the value of 288.

Let's fire up my TI-89 and write:
48/2(9+3)
Press enter
288

Nah...maybe I just hacked the programs. Let us go to the all powerful Google Calculator. who could hack into that?:
48÷2(9+3)
Click search
288

I can place pictures of the results if you want. If 8 computer programs aren't enough to convince people that this is the answer, perhaps we should merge this thread to my Stubborn People thread.  
"You haven't seen a tree until you've seen its shadow from the sky."
 
User avatar
northstardc4m
Posts: 3374
Joined: Fri Apr 28, 2000 11:23 am

RE: 48 ÷ 2(9+3)=?

Thu Apr 14, 2011 9:42 pm

Quoting einsteinboricua (Reply 148):

Let's try Java:
double x=48/2(9+3) (for which Java complains and asks that you put a '*' between the 2 and ( )
System.out.println(+x);

Answer: 288.

However, if I enter:
double x=48/(2(9+3)) (for which Java once again complains to put the asterisk)
System.out.println(+x)


How about Excel:
=48/2(9+3) (Excel claims there's an error and offers to correct it by placing an asterisk between the 2 and (.

Cell A1 will have the value of 288.

I can place pictures of the results if you want. If 8 computer programs aren't enough to convince people that this is the answer, perhaps we should merge this thread to my Stubborn People thread.

Seems to me 2 are agreeing to disagree as well.
Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety.

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