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And the answer is...
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Topik: 48÷2(9+3)=??? 2 or 288 |
1376 balasan
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Quote ( Marcelo Michelini @ April 15th 2011,20:57:02 )
is like if you use a bracket to separate terms in for example
2 + (5 * 5)
In maths u use the brackets for calculations not to separate terms or to make faces to laugh. :)
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Quote ( Chinmay Dhopate @ April 15th 2011,21:00:19 )
On calculators, yes. Never with pen/paper.
so you don't have a simplification way of writing a division of rational numbers in your calc without using brackets?
mine does and has saved me a lot of () in my life! :)
which also reducing brackets reduces human mistakes
Quote ( João Monteiro @ April 15th 2011,21:00:18 )
so
48:2(9+3)=48*1/2*(9+3)
and 48*1/2*(9+3)= ??
in any case as I read it, should be 48*1/2*1/(9+3)
again people, not a math problem! notation problem!! :D
Quote ( Chinmay Dhopate @ April 15th 2011,21:00:19 )
er... yes it is exactly that.
9/4 = 2.25, and it is 9 divided by 4.
I meant it as individual characters that later meet each other...
it is a full number, not something you can play with the 9 forgetting the 4...
please, don't turn this into an english problem :)
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#393 dikirim Apr 15 2011, 21:03:54 (terakhir disunting Apr 15 2011, 21:06:21 oleh Peter Holy)
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Sebut
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Quote ( João Monteiro @ April 15th 2011,21:00:18 )
a:b=ax1/b, right?
so
48:2(9+3)=48*1/2*(9+3)
and 48*1/2*(9+3)= ??
it´s 2, the correct result
Quote ( Marcelo Michelini @ April 15th 2011,21:03:30 )
again people, not a math problem! notation problem!! :D
true, should it be written on paper and not in "comp" language, the result would be obvious at first sight
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Quote ( Marcelo Michelini @ April 15th 2011,21:03:30 )
in any case as I read it, should be 48*1/2*1/(9+3)
no Marcelo!
48*1/2*(9+3)
should be
48*0.5*(9+3)
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Quote ( Marcelo Michelini @ April 15th 2011,20:57:02 )
it is not before or after, it is alltogether
as it is a rational number you can't take it away!
9/4 is 9/4 not nine and then divided by four
But I say it is the same :) It does not make any difference how you look on it.
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Quote ( William Irons @ April 15th 2011,20:41:50 )
I asked my wife and she said the answer was 2. So we know 2 is wrong.
:D that was the best post in this topic :D
No: 1
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Thats the answer from MatLab 7.8.0
48/2*(9+3)
ans =
288
48/(2*(9+3))
ans =
2
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Dont get why so many people get it wrong....! ;D
/ and ÷ are both divide symbols,
x , * or something in brackets like 2(9+3) is multiply....
You must do the multiplier first and get rid of the brackets....
So 48 divided by 2(9+3) becomes 48 divided by, 2 times (9+3) = 2 times 12 =24.
48 divided by 24 is always 2.
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Quote ( Ioannis Mikropoulos @ April 15th 2011,21:02:03 )
In maths u use the brackets for calculations not to separate terms or to make faces to laugh. :)
no sir, you use brackets for grouping calcs, this includes separating terms (not making faces though :) )
and some calcs are already grouped, so the use of brackets is redundant, as the example I showed to you
Quote ( João Monteiro @ April 15th 2011,21:05:12 )
no Marcelo!
48*1/2*(9+3)
should be
48*0.5*(9+3)
yes João !
as the denominator is not just 2, you can't multiply by the inverse of just a partial thing of the denominator
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lol...this is the funniest thread ever. there are already 14 pages of "deep"discussions and nothing has been resolved. sounds like political discussions in Czech Republic :P
288
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Quote ( Marcelo Michelini @ April 15th 2011,21:03:30 )
so you don't have a simplification way of writing a division of rational numbers in your calc without using brackets?
The one I have now does, but not the one I used before that.
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Quote ( João Monteiro @ April 15th 2011,21:00:18 )
Okay wiseguys, what's 13*7 then? 28?
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Just hope that none of you who says 2 , is a math teacher. That would be the worst thing. If a teacher cant solve that pretty easy thing then has to quit, from yesterday.
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Quote ( Chinmay Dhopate @ April 15th 2011,21:09:11 )
The one I have now does, but not the one I used before that.
then why can't you accept there could be a difference in notation between divisions and fractions?
the function is the same, but the order you do it might change everything as shown in this problem! :)
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Quote ( Michał Kubski @ April 15th 2011,20:59:11 )
Okay wiseguys, what's 13*7 then?
91?
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Quote ( Marcelo Michelini @ April 15th 2011,21:08:04 )
as the denominator is not just 2, you can't multiply by the inverse of just a partial thing of the denominator
but in this case
48÷2(9+3)
number 2 is the only term that we could put on denominator.
see this way:
48÷2(9+3)= (removing brackets)
48÷2x12= (changing division by multiplication)
48x0.5x12 = 288
to put 2(9+3) on denominator we need an extra pair of brackets
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Quote ( Liam Johnson @ April 15th 2011,21:13:35 )
91?
I read some theories that say it's 91, but it's just not convincing enough.
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Quote ( Michał Kubski @ April 15th 2011,21:16:34 )
I read some theories that say it's 91, but it's just not convincing enough.
13+13+13+13+13+13+13 ? :) now better ?:D
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Quote ( Marcelo Michelini @ April 15th 2011,21:13:04 )
then why can't you accept there could be a difference in notation between divisions and fractions?
the function is the same, but the order you do it might change everything as shown in this problem! :)
Because, mathematically, there isn't any difference.
Let's take your example of 9/4. In reality, we should not be writing 9/4, we should be writing 2.25. But, when you have fractions like, say 227/67 it is not realistic to write them in decimal format every time and so we write 227/67.
However, 227/67 is not a "number" like, say 9 is. It is a number like, 1+5 is. It is, still a division of 227 by 67, just like 1 + 5 is an addition of 1 and 5.
ed: But when you write them with pencil and paper and one on top of other, it seems like a different thing... I am not sure about that, because you have mixed fraction and stuff like that too.
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Quote ( Chinmay Dhopate @ April 15th 2011,21:19:48 )
Because, mathematically, there isn't any difference.
the differentation, once again, is on notation...
I have no idea where I have learnt the tiny notation difference between ÷ and /, but it is in my mind and I have applied it to many things and it works as a notation solution in many quality math softwares
so it is not my invention :)
with your equality symbol, you can't make a difference and you need to fill up the formula of brackets, which as far as I can remember, the idea was to simplify how it is written
so again, unless you can provide a simplified solution to write rational numbers in a division in a one line notation, then I will trust my way to write things down
and if you can't then the answer is not 288, is C, might be 2 or 288, depending on what notation has learnt the one who wrote the problem
I have said! :)
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Quote ( João Monteiro @ April 15th 2011,21:14:50 )
48÷2(9+3)= (removing brackets)
Removing the bracket is not just 9+3=12, it´s 2(9+3)=2*12=24. The bracket is there for reason and the reason is to multiply ALL terms in bracket by 2. So it´s either 2(9+3)=2*12=24 or 2*9+2*3=18+6=24. And then 48÷24=2
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Quote ( Michał Kubski @ April 15th 2011,20:59:11 )
Okay wiseguys, what's 13*7 then?
13*7
Let's write it like this
=39/3*7 (I leave brackets out just like all who says 48÷2(9+3)=2 does, then I count from right to left, just like all who says 48÷2(9+3)=2 does)
=39/21
=1.85714285714
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Quote ( Marcelo Michelini @ April 15th 2011,20:44:06 )
just a simple question I am intrigued as I got no answer
have you ever wrote a rational number using "÷"??
i do prefer to write them 0.5 instead of (1/2)!
and in my programming coding i am using brackets, it is easier for me to follow the calculations there, probably some programmers with experience might say it is not optimal, but like i said, i want to leave out any doubt ang get the result i want! longer expressions i prefer to split them in more lines, easier to debug!
someone said here about mathlab, i don't have it installed anymore, but i am sure it will calculate the right answer, only one! :)
anyone still having mathematica or mathcad installed to see what notations are used in there?
Quote ( Marcelo Michelini @ April 15th 2011,21:03:30 )
has saved me a lot of () in my life! :)
do you write such math expressions on the computer everyday?
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Quote ( Cristian Iordache @ April 15th 2011,21:41:48 )
i do prefer to write them 0.5 instead of (1/2)!
and 1/3?
writing decimals would give you troubles :)
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Quote ( Marcelo Michelini @ April 15th 2011,21:44:52 )
and 1/3?
0,(3) ?; >
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Quote ( Marcelo Michelini @ April 15th 2011,21:44:52 )
and 1/3?
writing decimals would give you troubles :)
1/3 = 0.(3)
like i said, i am a big fan of brackets! :)
so, the topic title i would write:
x = 48 / ( 2 * ( 9 + 3 ) ); if i need the 2 as result
or
x = ( 48 / 2 ) * ( 9 + 3 ) ; if i need the 288!
someone might say i wasted a lot of my time writing so many brackets, but i am sure everyone will understand what i meant, and everyone will get the same result as me!
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Quote ( Cristian Iordache @ April 15th 2011,21:41:48 )
do you write such math expressions on the computer everyday?
no, but I studied engineering like 10 years ago, and back then I did :)
Quote ( Rafal Celejewski @ April 15th 2011,21:45:40 )
0,(3) ?; >
that's just awful! :p
simplify!! :)
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math math math...gives me headaches sometimes :(
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