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Amen. After much cogitating, this should be expressed as:

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

48/(2[9+3])=2 or

48

2(9+3)

Thank you for your support! ^^

the meaning of the problem is perfectly clear. people are just adding phantom parenthesis where they don't belong.

How do you mean where they don't belong. The original equitation is just not proper math since it can't be solved. You can add brackest as much as you want. Since it's not proper math, I can claim the answer is 654654 and still be 'right'.

the meaning of the problem is perfectly clear. people are just adding phantom parenthesis where they don't belong.

No, 48/2(9+3) is just sloppy. depending on the method a person is taught it can be come out as either 288 or 2. If people use the PEDMAS method they are more likely to get 288. Any math problem should be clear from the get go. Problems like this is why you see the 48 over 2(9=3) or 48/2 over (9+3) in really important equations. There is NO ambiguity allowed.

No, 48/2(9+3) is just sloppy. depending on the method a person is taught it can be come out as either 288 or 2. If people use the PEDMAS method they are more likely to get 288. Any math problem should be clear from the get go. Problems like this is why you see the 48 over 2(9=3) or 48/2 over (9+3) in really important equations. There is NO ambiguity allowed.

sloppy education is no excuse for doing a question incorrectly. I learnt it using the actual rules instead of some stupid mnemonic like BEDMAS (what my high school taught) and both get the same result. this is elementary level mathematics, an omitted multiplication sign shouldn't be causing so much (ANY, really) confusion.

And trust me, when math is the thing deciding just how much bang-bang you need to drop a bridge and how how are you need to be back from said bang-bang to not be wounded or killed, while actually being able to actually drop said bridge the first time, ambiguity is NOT allowed. the equation MUST be expressed EXACTLY as intended.

And trust me, when math is the thing deciding just how much bang-bang you need to drop a bridge and how how are you need to be back from said bang-bang to not be wounded or killed, while actually being able to actually drop said bridge the first time, ambiguity is NOT allowed. the equation MUST be expressed EXACTLY as intended.

of course, in that case it'd be properly expressed rather than as a linear equation, but that doesn't mean that this particular equation is ambiguous in any way.

sloppy education is no excuse for doing a question incorrectly. I learnt it using the actual rules instead of some stupid mnemonic like BEDMAS (what my high school taught) and both get the same result. this is elementary level mathematics, an omitted multiplication sign shouldn't be causing so much (ANY, really) confusion.

Do 4z ? 2z

Now do 4*z ? 2*z

Post your answers to both.

And trust me, when math is the thing deciding just how much bang-bang you need to drop a bridge and how how are you need to be back from said bang-bang to not be wounded or killed, while actually being able to actually drop said bridge the first time, ambiguity is NOT allowed. the equation MUST be expressed EXACTLY as intended.

sloppy education is no excuse for doing a question incorrectly. I learnt it using the actual rules instead of some stupid mnemonic like BEDMAS (what my high school taught) and both get the same result. this is elementary level mathematics, an omitted multiplication sign shouldn't be causing so much (ANY, really) confusion.

Oh come on, this has nothing to do with sloppy education. The question is ambiguous. It is unclear what is actually meant. No interpretation is correct, since the question is just not clear enough. You can not omit a multiplication sign if it creates this much confusion. There are multiple different interpretations of this problem, but the only mathematically correct solution would require brackets to be added to make the order of operations in this specific question completely clear. You should not be relying on left-to-right or doing multiplication before division, neither of these 'tricks' is mathematically correct.

Oh come on, this has nothing to do with sloppy education. The question is ambiguous. It is unclear what is actually meant. No interpretation is correct, since the question is just not clear enough. You can not omit a multiplication sign if it creates this much confusion. There are multiple different interpretations of this problem, but the only mathematically correct solution would require brackets to be added to make the order of operations in this specific question completely clear. You should not be relying on left-to-right or doing multiplication before division, neither of these 'tricks' is mathematically correct.

the only reason there is confusion is because people are treating an omitted multiplication sign as something special. how does that reflect poorly on the fact that you CAN omit multiplication signs?

only BODMAS can tell you the answer :laugh:

Left-to-right is not mathematically correct. If you ever need to rely on left-to-right, something is wrong and you need more brackets in the original question, or solve it in another way.

48/2(9+3)

48/2*1(9+3)

post YOUR answers to both.

48/2(9+3) | Distributive multiplication implied by multiplication by juxtaposition

48/(2?9 + 2?3) | Evaluate brackets

48/24 | Division

2

48/2*1(9+3) | Distributive multiplication implied by multiplication by juxtaposition

48/2*(1*9 + 1*3) | Evaluate brackets

48/2*12 | Division and multiplication.

288

Now you answer my questions

48/2(9+3) | Distributive multiplication implied by multiplication by juxtaposition

48/(2?9 + 2?3) | Evaluate brackets

48/24 | Division

2

48/2*1(9+3) | Distributive multiplication implied by multiplication by juxtaposition

48/2*(1*9 + 1*3) | Evaluate brackets

48/2*12 | Division and multiplication. LTR

24*12

288

Now you answer my questions

My brain just exploded

the only reason there is confusion is because people are treating an omitted multiplication sign as something special. how does that reflect poorly on the fact that you CAN omit multiplication signs?

An omitted multiplication sign isn't something special, but it can create a special and ambiguous (unclear) equitation when used in 'unfitting' situations. Mathematics are all about clarity. If there are two possible 'interpretations', it's not mathematics anymore, and you need to specify more.

The only answer is 288. It's math. I can't believe that there is a discussion on this.

It's not math. The original question is not mathematically correct, so you can not use math to solve this problem.

If people still think there is a 'correct' answer, read this:

http://mathforum.org/library/drmath/view/57021.html

THERE IS NO CORRECT ANSWER SINCE THE QUESTION IS UNCLEAR.

48/2(9+3) | Distributive multiplication implied by multiplication by juxtaposition

48/(2?9 + 2?3) | Evaluate brackets

48/24 | Division

2

48/2*1(9+3) | Distributive multiplication implied by multiplication by juxtaposition

48/2*(1*9 + 1*3) | Evaluate brackets

48/2*12 | Division and multiplication.

288

Now you answer my questions

and you don't see how ridiculous that is?

My brain just exploded

:laugh:

Left-to-right is not mathematically correct. If you ever need to rely on left-to-right, something is wrong and you need more brackets in the original question, or solve it in another way.

An omitted multiplication sign isn't something special, but it can create a special and ambiguous (unclear) equitation when used in 'unfitting' situations. Mathematics are all about clarity. If there are two possible 'interpretations', it's not mathematics anymore, and you need to specify more.

It's not math. The original question is not mathematically correct, so you can not use math to solve this problem.

i can basically agree with your point, and of course it's always better to use more brackets. but the fact is we do have a left-to-right convention which resolves the consistency issue, which is the standard. which means that the equation is perfectly valid according to standard mathematical conventions.

An omitted multiplication sign isn't something special, but it can create a special and ambiguous (unclear) equitation when used in 'unfitting' situations. Mathematics are all about clarity. If there are two possible 'interpretations', it's not mathematics anymore, and you need to specify more.

It's not math. The original question is not mathematically correct, so you can not use math to solve this problem.

Nope. It is math. The only issue here are people's poor interpretation of it. People are wanting to put parens in places where they don't exist.

See, for most people that are wrong, they cite BODMAS as the reason, as they interpret it as BRACKETS, ORDERS, DIVISION, MULTIPLICATION, ADDITION, SUBTRACTION.

this is wrong

BODMAS = BRACKETS, ORDERS, DIVISION and MULTIPLICATION, ADDITION and SUBTRACTION.

again for those who cannot spot the difference;

Brackets

Orders

Division and Multiplication

Addition and Subtraction

See, for most people that are wrong, they cite BODMAS as the reason, as they interpret it as BRACKETS, ORDERS, DIVISION, MULTIPLICATION, ADDITION, SUBTRACTION.

this is wrong

BODMAS = BRACKETS, ORDERS, DIVISION and MULTIPLICATION, ADDITION and SUBTRACTION.

again for those who cannot spot the difference;

Brackets

Orders

Division and Multiplication

Addition and Subtraction

actually, most of them are inserting extra brackets around 2(9+3) because of juxtaposition

i can basically agree with your point, and of course it's always better to use more brackets. but the fact is we do have a left-to-right convention which resolves the consistency issue, which is the standard. which means that the equation is perfectly valid according to standard mathematical conventions.

There are conventions, but left-to-right is not one of them. One convention from the American Mathematical Society is this one:

"multiplication indicated by juxtaposition is carried out before division."

So, the 'conventional' answer is 2. However, it is not mathematically correct. Mathematically, the answer is unclear. 288 is mathematically wrong AND unconventional.

End of story.

4*3/6*5 on the other hand does have a simple solution. 4*3/6*5 should be solved, not by left-to-right, but by defining each term differently, like this: (4)*(3)*(1/6)*(5). Even here people will be confused and some people might do (4*3)/(6*5), which is not correct.

There are conventions, but left-to-right is not one of them. One convention from the American Mathematical Society is this one:

"multiplication indicated by juxtaposition is carried out before

division."

So, the 'conventional' answer is 2. However, it is not mathematically correct. Mathematically, the answer is unclear. 288 is mathematically wrong AND unconventional.

People here are confusing themselves because we are representing the math on a single line on the screen instead of written out on multiple lines on a peice of paper. They are wanting to place parens around portions that would make sense to them even if it is incorrect.

The question is:

48/2(9+3)

While people want to see it as "48/(2(9+3))" but that isn't what is being asked. They are putting parens in places where they don't exist.

48 divided by 2 and multiplied by (9+3).

Answer MY questions, then we'll see.

I looked back at your earlier posts, and agree with the interpretation offered by W|A. For the reasons I already stated earlier.

There are conventions, but left-to-right is not one of them. One convention from the American Mathematical Society is this one:

"multiplication indicated by juxtaposition is carried out before division."

So, the 'conventional' answer is 2. However, it is not mathematically correct. Mathematically, the answer is unclear. 288 is mathematically wrong AND unconventional.

End of story.

http://mathforum.org/library/drmath/view/54342.html

http://mathforum.org/library/drmath/view/57021.html

back where we started. juxtaposition was never taught in any country where I've studied, but left-to-right in every one of them.

edit: though certainly more parenthesis would be desirable in any serious context.

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