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48÷2(9+3) = ? watch

• View Poll Results: 48/2(9+3)
2
117
52.47%
288
106
47.53%

1. Can we make this thread a 'sticky'.
2. I thought the ultimate answer was 42 myself...
3. (Original post by HistoryRepeating)
You are still wrong. As I've said, when using vertical fractional notation, the vertical positioning of elements of the equation effectively functions as parentheses.
Sorry, skipped the beginning of this particular sub-convo, so may be missing your point, but what IS your point? Sure, if we WERE using vertical fractional notation this question would be clearer. But we're not.
4. (Original post by HistoryRepeating)
Thanks for the patronising reply, I'm 25 years old with a F. Maths A at A-level and a highly numerate job.

Maths notation is really clear on this point. The answer is 288.

You are still wrong. As I've said, when using vertical fractional notation, the vertical positioning of elements of the equation effectively functions as parentheses.
What do you want, a ****ing medal? You have maths A-level, so you must clearly be the most qualified here, because no-one here has a maths degree or a theoretical physics PhD or anything like that.

There seems to be a reasonable consensus amongst the qualified individuals that the statement is ambiguous, and to be honest with you its somewhat irrelevant as no-one who actually does maths for a living would ever write out an equation in such an imprecise manner. Perhaps you're the exception to the rule in your "highly numerate job". lol
Sorry, skipped the beginning of this particular sub-convo, so may be missing your point, but what IS your point? Sure, if we WERE using vertical fractional notation this question would be clearer. But we're not.
He doesn't have one. He's trying to look clever by contradicting other people but he's out of his depth.
6. Just because 2(9+3) is not in brackets itself does not mean that its not treated as one term. If it was meant to be 48/2 x(9+3) it would have been written (9+3) x 48/2 or 48/2 x (9+3)the fact the 2 is right next to the bracket says its 2 times the thing in brackets, not the whole term times thing in brackets.
7. (Original post by py0alb)
He doesn't have one. He's trying to look clever by contradicting other people but he's out of his depth.
Whoops, probably shouldn't have got involved in this particular one, by the look of it. Also, ouch. :P
8. (Original post by Jallenbah)
NO.

Multiplication and Division are THE SAME PRECEDENCE. How many times do I have to say this???

When 2 operations are the same precedence you work LEFT TO RIGHT.
Of course it is ambiguous. It is a rather bold claim that something as vague, ill-defined and flimsy as "work left-to-right" is an absolute, unambiguous axiom. This is why you simply don't write out expressions in such a stupid, in-line format. The only time this is appropriate is when it is being used as a computational expression, at which point you require far more disambiguation in the form of brackets because the behaviour of the computation in this situation is not universally defined and is language-dependent, since the direction of associativity will vary dependent on language, as will whether or not 2(9+3) is treated as an implicit multiplication or, as smiffhead points out, a term with coefficient.
9. Wow. This basic arithmetic question has received 22 pages of discussion (combining the two threads) in about 13 hours. Just wow.
10. (Original post by Planto)
Of course it is ambiguous. It is a rather bold claim that something as vague, ill-defined and flimsy as "work left-to-right" is an absolute, unambiguous axiom. This is why you simply don't write out expressions in such a stupid, in-line format. The only time this is appropriate is when it is being used as a computational expression, at which point you require far more disambiguation in the form of brackets because the behaviour of the computation in this situation is not universally defined and is language-dependent, since the direction of associativity will vary dependent on language, as will whether or not 2(9+3) is treated as an implicit multiplication or, as smiffhead points out, a term with coefficient.

Abso-****ing-exactly.
11. (Original post by Dragon)
Wow. This basic arithmetic question has received 22 pages of discussion (combining the two threads) in about 13 hours. Just wow.
If it were a basic arithmetic question it would have just been answered; this is a question about notation. And it dissolved some time ago into a squabble between three categories of people:
(c) People who think the notation is ambiguous (and may or may not give preference to one of the two answers)

And, ironically perhaps, it seems that the people in categories (a) and (b) are the people who don't have much in the way of an advanced maths education.

What's more amusing is how wound up some people are getting about this. I mean, typing in capital letters?! This extreme level of rage must be calmed!
12. The way in which the question is presented on this forum is the problem, for example, we wouldn't be having this discussion if you could put 2(9+3) directly under 48 because that would give the clear answer of 2.
13. According to this http://mathforum.org/library/drmath/view/57222.html, it's 288 as paranthesis are exactly the same as multiplication which is on the same level as division and should therefore be solved left to right

however according to this http://www.purplemath.com/modules/orderops2.htm, it's 2 as paranthesis does outrank division and therefore should be solved first.

There does not seem to be a generally accepted way of resolving the conflict which explains why even the best scientific calculators are giving different solutions to the problem

Let's just agree that the question is too ambiguous and solid arguments can be found for both camps.
14. The thing with maths is that it shouldn't be 'ambiguous', though. Just because people interpret things differently, it doesn't mean that both are correct.

You could argue however that if somebody was to write this, nobody would write it in a one line style that the OP has. I think DFranklin wrote a few pages back that if two different people wrote it (a Uni lecturer/a GCSE student), then the interpretation would be different. Whilst this is true, I don't think it's the point. It can't be correct to interpret in both ways, otherwise there'd be no point in a common mathematical notation, principles and axioms.

I'd say that the 'correct' answer is 288; and I'd say any other answer such as 2 could be 'assumed' because of how it's written, but it's not correct.
15. Well I think the answer is 2, although I can see why it is ambiguous. But 22 pages, really?
16. It's 2. In algebra x(3+4) for example, you times everything inside the bracket by everything on the outside. 4 X x = 4x 3 X x = 3x 4x + 3x = 7x.

48÷2(9+3) = 48 ÷ (9+3 x 2) = 2

When there's a number next to a bracket without a sign, it means multiply by the bracket first, then division.
17. If I try this on my calculator, and it says the answer's 2, I'll feel like it has betrayed me.
18. (Original post by Dragon)
Well I think the answer is 2, although I can see why it is ambiguous. But 22 pages, really?
Welcome to the internet! Cuppa tea?

EDIT: For what it's worth, half of the posts are people who haven't read any of the other posts and just want to splurge their opinion into the crevices of a TSR thread. Half of the posts are people arguing with what the other half have said, and subsequently with each other. As long as the former half keep posting (which they probably will for a while), there will be more pages to come.
19. 48\2(9+3)=288, BUT HOW? LET ME SHOW YOU

FIRST U GOT NEED TO GET RID OF ALL DE BRACKETS and It would be turning into multiple sign

48/2*(THE star is multiple)12=

48/2*12= here's where most of the people get confused, well there's a simple formula for dis confussion and that's when you see Divission & Multiple signs, you have to start from de Divission, so here we go:

48/2=24x12=288.

This is the right Answer anyone get this answer, take it from me YOU ARE RIGHT.... THAT'S IN CAPITAL LETTERS....

THANK YOU SO MUCH

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