re: Spinoff: X=6/2(2+1)

I personally work it to 1, but I totally could work it the next day and get 9. If I got it wrong on an exam, is argue until I got credit .

Its like the sentence below. If you don't specify with the necessary punctuation, the meaning can be totally different. Same as in that math problem. Neither is wrong, because the equation leads to ambiguity.



"Most of the time, travellers worry about their luggage.”


“Most of the time travellers worry about their luggage”

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And the left to right argument is asinine.

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Except, this is how it's done.

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Different people can interpret it different ways.

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It's a mathematical equation, not a Shakespearean stanza. The answer is either correct or its not. It's not up for interpretation.

You better never take a higher level math course. In this case, it does matter since there is no context to explain what the equation applies to. The whole branch of theoretical mathematics is based on interpretation...

People are essentially inserting parentheses to get to the answer of 1. Since the parentheses are not there, you cannot put 2(2+1) in the denominator.

If you take it how it is written, it reads 6 divided by 2 multiplied by the sum of 2+1 or 6 multiplied by 1/2 multiplied by the sum of 2+1:
6*(1/2)*(2+1)

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You read it that way because you are reading it left to right. Rules that govern reading a sentence do not govern math equations. You are right that people who answer 1 choose to do the order of operations as if the parenthesis were put that way. But those answering 9 are doing the same thing. You can't assume people will do operations left to right, because that's not a rule.

As someone else said, its up for interpretation until its written correctly.

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OK we can all acknowledge using your basic keyboard symbols makes complex equations harder to communicate.

That being said, we know the limitations of this style, and we have to add a parentheses to make distinctions. Just like when I type an equation into R, or any other software that has the same language limitations, (I.e., unlike Maple and Mathematica which allow for a more formal representation) if I don't put the parentheses, it doesn't assume they are there.

So only one answer (1) requires an assumption of a symbol that is not clearly specified. I get the reasoning, but it requires an assumption that the other one does not so arguing that they both require one to make a similar assumption is simply not true.

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You are right that people who answer 1 choose to do the order of operations as if the parenthesis were put that way

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Yes, they chose to do it that way, which is wrong. Those answering 9 are doing the problem as its stated... You're not convincing anyone that you took level 3000-4000 math courses

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and if they forgot to put the symbol needed to accurately communicate the problem given the software

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And that's the whole point of this argument. The keyboard, the ability to write equations on a forum, and the way you write the problem. / is equal to ÷. But sometimes, when written in a straight line like this case, people interpret / as if the problem was written like this:

x=____6_____
2(2+1)

as if everything after the / is under what comes before it.

A(B+C)shows the multiplying (AB+AC). If you do that operation first, which is completely acceptable since multiplication takes place at the same time as division in order of operations, then the parenthesis are now in the denominator. There is NOTHING that states you must do the division in the equation before distributing that A across the argument in the parenthesis except left to right. That's how people come up with 1. You state that you need to show the parenthesis around the entire denominator to do that operation first. I'm saying that you have to put the parenthesis around (6/2)to do that operation first. You are only doing that operation first because you are reading left to right. That is not enough to define the order of operations.

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And that's the whole point of this argument. The keyboard, the ability to write equations on a forum, and the way you write the problem. / is equal to ÷. But sometimes, when written in a straight line like this case, people interpret / as if the problem was written like this:

x=____6_____
2(2+1)

as if everything after the / is under what comes before it.

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Yeah i mean I get the issue, and why people would interpret it that way. I'm just saying that without any context, one should interpret it as written and not add any additional assumptions.