48÷2 (9+3) argument

Hahaha so i've given this to the office but just the 48/2x part, quite funny.

Look I agree it's 288 if you follow the rules without adding your own brackets to clarify an intentionally ambiguous expression that should have been written as
48
-- * (9+3)
2

or

48
----
2(9+3)

however it's trolling because no one in their right mind should write it as 48/2(9+3). If you gave me a spec with this as some function I would most likely slap you and tell you to add parenthesis.


it's the same as writing

1/2/2
do you mean
1
--
(2/2)

or

(1/2)
----
2
??

using the rules 1/2/2 = 1/4 and not 1 as a lot will no doubt argue..
but again it's written to be intentional ambiguous...
 
nakedpeanut said:
1/2/2
Click to expand...
Left to right, couldnt be any simpler. Unless you are chinese and are used to reading right to left.

edit: to prove how utterly silly you are being

What is 5-2+1 =
Is it 4 (using the rules) or is it 2 (using the mystical brackets you like so much around 2+1)
Do we assume there are magical brackets in there? Or do we simply go left to right?....
 
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garp said:
There is NO different way to do this, it is not debatable. If kids are somehow being taught to calculate equations differently to the rest of the planet then we really are up **** creek with our educational system. It is not a matter of the "way" older or younger people are taught. It is an inviolable rule of mathematics.
Click to expand...

Well scientific calculators seem to disagree with you:

16h6ja8.jpg


noxibox said:
So 48/2*y is not the same as 48/2y? What operation is occurring in the case of 2y (since it isn't multiplication)? Of course if we're talking about computer code, then 2y could be a, quite probably illegal, variable name.
Click to expand...

48/2*y
would be
24*y

while
48/2y
would be
24/y

if you had:
48/2sinx
you would first factor out the 2 to be left with:
24/sinx.
 
Archer said:
Left to right, couldnt be any simpler. Unless you are chinese and are used to reading right to left.

edit: to prove how utterly silly you are being

What is 5-2+1 =
Is it 4 (using the rules) or is it 2 (using the mystical brackets you like so much around 2+1)
Do we assume there are magical brackets in there? Or do we simply go left to right?....
Click to expand...

hahaha but I'm not.. and your math fails there: 5 -1(2-1) = 4 :p
let x=1 ,y=2
x/y/y
1/2/2 =1/4

let x= 1+6, y = 2-1
1+6/2-1/2-1
= 2.5?
or is it
(1+6)/(2-1)/(2-1)
=7?

My point was parenthesis is very important. yes there are trivial equations where it is not needed. but in many case ambiguity can arise when they are not used.
 
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Didn't know we had so many maths experts on this forum. We should form a club, meet up for a beer and discuss the genius of Lagrange and Euler :D
 
garp said:
Well then they had a pretty piss poor education.
Click to expand...

noxibox said:
Certainly explains university professors complaining about students being unable to do basic mathematics.

Most often the examples are of this form - 5 + 6(2+4). That may be why some people erroneously start to think of the 6(2+4) part as somehow unique. Only a teacher who is clueless would teach them that 6(2+4) is not exactly the same as 6*(2+4).
Click to expand...

Thinking back I remember why.
Our tests were printed, so teachers being lazy never did it as:
48
-- x (9+3)
2

If they wanted us to do it this way they would write it as 48/2.(9+3) or 48/2*(9+3)
If they wrote 48/2(9+3), we had to interpret it as:
48
-----
2(9+3)
 
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nakedpeanut said:
Thinking back I remember why.
Our tests were printed, so teachers being lazy never did it as:
48
-- x (9+3)
2

If they wanted us to do it this way they would write it as 48/2.(9+3) or 48/2*(9+3).
If they wrote 48/2(9+3), we had to interpret it as:
48
-----
2(9+3)
Click to expand...

Correct.

I just thought of another way to do this. Let's substitute 2 for x

So:

48/x(9+3)

Now answer can be 288 or 2

if 48/x(9+3) = 288

48/x(12) = 288
48 = 288*12x
48 = 3456x
x = 0.0138888888

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

Well Look at that :)
 
Qwikslver said:
Correct.

I just thought of another way to do this. Let's substitute 2 for x

So:

48/x(9+3)

Now answer can be 288 or 2

if 48/x(9+3) = 288

48/x(12) = 288
48 = 288*12x
48 = 3456x
x = 0.0138888888

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

Well Look at that :)
Click to expand...

lol sorry to play both sides of the fence put I'm trying to show why parenthesis is needed in equations:
if 48/x(9+3) = 288

48/x*(12) = 288
48/x *12= 288
576/x =288
x= 576/288
x=2 :)
 
Ho3n3r said:
Is this your way of talking to yourself?
Click to expand...

Nope. I'm talking to you.

There is no correct answer to this equation. It's ambiguous and poorly formatted. This conclusion has been arrived at and stated over and over again throughout the previous 28 pages of this thread. So you are beating a dead horse by stating "it's 2."
 
In fact there is only one why of looking @ this problem:

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

48
--------------
2(12)

48
--------------
24

= 2
 
Humberto said:
It seems opinion is divided, but with mathematicians, physicists and engineers favouring the answer 2.

(Google it.)
Click to expand...
They are just as divided.

Qwikslver said:
16h6ja8.jpg
Click to expand...
All that really shows is how the calculator was programmed. One treats the parenthesis as a term while the other adds the *.

And there's the problem. In school we were all taught that this is a term. That's only because we used a division sign back in grade 2. The correct interpretation is that the brackets merely imply * so applying the rule of left to right it's 288. Ambiguity arises only because people don't apply the rules properly.
 
htpc said:
If it was stated 48 / 2 x (9+3) then it would be

48
--- (9+3)
2

but

48 / 2(9+3)
= 48 / (2*9 + 2*3)
= 48 / 24
= 2
Click to expand...
Why? Does a term appearing next to brackets not imply multiplication?
 
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