48÷2(9+3) = ????

[Terrh]

its 288.

Did everyone forget BEDMAS?

[Tony-R32]

lololololololol!

Seriously who cares anymore?

[esh]

IT'S AMBIGUOUS.....really depends on how you parse the statement.

I'm in compsci, so i would see it as 288....though i can see the argument for 2 as well. The poll results are split roughly in half, so it's quite an ambiguous statement.

Several programming languages don't allow bracket to bracket (or number to bracket) multiplication. They explicitly force you to use the * operator for multiplication (which would lead to 288 in the example above).

Why would these programming languages make you use this?....to avoid ambiguous input that leads to arguments such as this whole thread!!


When you're doing calculations, you want to do two things:

1) Be aware of how your calculator/program/whatever parses statements. That is, what order of operations it uses.

2) Use well formed, explicit statements that avoid ambiguity.

No need to get worked up over math!

[Snake556]

Rofl! That's fantastic.

HEY! I have a good idea... Eff the math, let's go drive Skylines, since the weather's nice now

[leeaspin]

this thread has gone too far!

fyi canucks won thats all that matters!

[leeaspin]

how about we debate about putting a blonde in a round room and telling her to pee in the corner...whats gunna happen? MUCH better debate!!!

[raijin-xiii]

You made an error with this calculation:

48*2(9+3)
=48*2(9)+2(3)
=48*12
=576

It should be

48*2(9+3)
=48*(2*9 + 2*3)
=48*24
=1152

lmao that's embarrassing... I completely forgot to multiply by 2 in there. talk about losing credibility in the middle of an argument LOL

Let's look at this questions algebraically. If we replace any of the numbers in the expression with a a letter, like 'x', then we should be able to rearrange and solve and get that original number.

Let's replace the 48 with x and start with setting the expression equal to 288 as you suggest:

288 = x ÷ 2(9 + 3)
288 = x ÷ 2(12) -- simplify first
288 = x ÷ 24
288 x 24 = x
6912 = x


Now setting the expression equal to 2 and solving for 'x':

2 = x ÷ 2(9 + 3)
2 = x ÷ 2(12) -- simplify
2 = x ÷ 24
2 x 24 = x
48 = x

which is what was in the original expression.

So, following algebra rules, 288 doesn't work as an answer.

I WAS very impressed with this reasoning, but at second glance, you've pretty much done the EXACT order of operations as you've been doing all along... meaning this is basically a fruitless effort and shows nothing new at all. watch how I've been doing it:



see. I get 48 because I'm still doing the division before multiplying the sum of the brackets.

what you're using is the "lack of consensus on the value" of the theory of "implied multiplication" as shown in the link posted on page 7:

you can actually thank this description for explaining more clearly what you've been trying to tell us (me) lol.

I've looked into it further and discovered this on the Texas Instruments (the calculator brand) site:

Notice that it basically states that implied multiplication was invented for calculators to use when there are variables in the equation; it keeps them together instead of having to use parenthesis. I'm not saying that "this implied multiplication theory is misinterpreted and wrong" but I just figured it's an interesting piece of info.

Which, after typing the paragraph above, is also mentioned in this little write-up, alongside absolutely schooling everyone arguing about this:


If you're going to read anything, read the last paragraph.
(I also lolled at the last two sentences because it's the lack of this knowledge which turned this into the internet's fury-of-the-week).

our_kid, I'm not saying this because of this finding, but I apologize for being rude in my previous posts. I'm sure I've been misunderstanding what you've been trying to say and I was being a **** about it. I had never heard of implied multiplication until now. You explained yourself well in your last post which helped clear up a few things for me and I'd shake your hand and buy you a coffee if I could out of respect.
__________________________________________________ ________

SUMMARY:

- The answer 288 is correct when using traditional BEDMAS and its "explicit multiplication" to support your argument.

- The answer 2 is correct when using the "implied multiplication" theory to support your argument.

- The answer 2 is wrong when using "distributive property" or other poorly-interpreted mathematical operations to support your argument. You may have gotten AN answer that is correct, but your explanation is wrong and therefore you made an error and have a correct answer out of sheer luck thanks to the existence of "implied multiplication."

- The QUESTION ITSELF is wrong because of its ambiguity. This is a troll question. We've been duped.

__________________________________________________ ________

[raijin-xiii]

AND THE INTERNET IS IN BALANCE ONCE MORE.....for the time being.

[Snake556]

IT'S FINALLY OVER! NYAN CAT HAS SPOKEN!

And now...




We drive.

[our_kid]

I agree, the way the question is written is like an English sentence written with terribly ambiguous grammar. It's why pretty much after grade 10, the ÷ is rarely used, and instead division represented as a rational expression. So, the question is forced to be stated as:

48 (9+3)
----
2


OR

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


My argument was just that in school today, students are taught to distribute a number adjacent to a bracket with no operation sign indicated before carrying out any other division or multiplication. I actually gave the same question with different numbers to a grade 11 class today hoping that students would do it the two ways and get two different answers and we could have a discussion on the importance of 'math grammar' (and just to satisfy my own curiosity as to what way they'd do it). All 29 of them did it with distributing the number through the bracket before dividing (like they should have). So, the discussion I was looking for never got going. Instead they just thought I was being ignorant thinking that some of them might get the other answer doing the division/multiplication left-to-right. It was a teachable moment 'fail'.

I also tried using the TI graphing calculators the school has and typing it in both ways. Inputting "48/2(9+3)+ outputs "2" as the answer. Inputting "48/2*(9+3) outputs "288" as the answer.

Finally, I found this from the American Mathematical Society: http://www.ams.org/mresubs/guide-reviewers.html

"...multiplication indicated by juxtaposition is carried out before division." Meaning, numbers multiplied together with no 'x' or dot between them, should be carried out first.



That's all. I've said my piece.

[cyberspyder]

I agree, the way the question is written is like an English sentence written with terribly ambiguous grammar. It's why pretty much after grade 10, the ÷ is rarely used, and instead division represented as a rational expression. So, the question is forced to be stated as:

48 (9+3)
----
2


OR

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


My argument was just that in school today, students are taught to distribute a number adjacent to a bracket with no operation sign indicated before carrying out any other division or multiplication. I actually gave the same question with different numbers to a grade 11 class today hoping that students would do it the two ways and get two different answers and we could have a discussion on the importance of 'math grammar' (and just to satisfy my own curiosity as to what way they'd do it). All 29 of them did it with distributing the number through the bracket before dividing (like they should have). So, the discussion I was looking for never got going. Instead they just thought I was being ignorant thinking that some of them might get the other answer doing the division/multiplication left-to-right. It was a teachable moment 'fail'.

I also tried using the TI graphing calculators the school has and typing it in both ways. Inputting "48/2(9+3)+ outputs "2" as the answer. Inputting "48/2*(9+3) outputs "288" as the answer.

Finally, I found this from the American Mathematical Society: http://www.ams.org/mresubs/guide-reviewers.html

"...multiplication indicated by juxtaposition is carried out before division." Meaning, numbers multiplied together with no 'x' or dot between them, should be carried out first.



That's all. I've said my piece.

Iuno if it's just me, but 2 is what I've been taught all throughout my years in Canada in high school, carried this over to engineering in university. Ambiguous question.

[Snow]

/unsubscribed.