Simple math problem posted on the internet

I think the answer is 9. You should be able to paste the formula verbatim into JavaScript or whatever and get this answer.
 
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When written like that, the answer would be 1.
I’ve been taught that a division is to be performed before an addition or subtraction. And the order of operations is from left to right.
How do you get that result?

If you do the division from left to right, the first step is 3/1=3, which you then divide by 3 getting 1. Then you do the additions 9 -1 + 1 = 9. This is also the result you get by entering the formula in Excel, or as lord James did, writing a program.

To get the answer 1, you'd have to do the division from right to left, first doing 1/3=0.3333..... and then dividing 3 by that.

Methinks.

pibbur who is confused.
 
I think Myrthos was referring to LuckyDay's video, which appears to write the calculation differently. It uses a fraction instead of a division, which may change the logic.
 
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Correct, that was what I was referring to.
You start at the left with 9 but before the subtraction can take place the division needs to be executed, which in the case of the video is 3 divided by a third, which makes 9. 9-9 equals 0 and adding a 1 gives 1 as a result.
 
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I think that's probably right, as a fraction is a way of expressing a number, rather than an operation, as such.
 
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Aha! The OP and the film present not the same problem (didn't watch the film until now).

In the OP the expression is given as 9-3/1/3 +1, which also the film says will be 9. But the graphical presentation of the expression really translates to - as the film also says, 9-3/(1/3)+1 which gives 1.

So, if you solve the expression as presented in the film you get 1. I assume that is the original problem. And if you solve the (incorrect) version of the formula in the OP, you get 9.

BTW: I'm a bit surprised that this (the formula given in the film) has gone viral as a really difficult problem, and that only 60% could solve it, as this is ground school mathematics. Hmmm.. sounds a bit arrogant. Does it?

pibbur who prefers formulas like e^(PI*i)+1 which unambiguously is 0.

PS: I've decided to, when I become the most powerful man in the world, to force everyone to write formulas using RPN (postfix notation). DS.

PPS: And also to exclusively use binary : 1001 1 11 1 11 / / - + DS.
 
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Yes, I would say they are two different expressions, depending on whether 1/3 is presented as a fraction or a division operation.
 
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Yes, I would say they are two different expressions, depending on whether 1/3 is presented as a fraction or a division operation.

But isn't a fraction a division operation to begin with? Just one that remains unexpressed:

A fraction is a division expression where both dividend and divisor are integers (typically called the numerator and denominator), and there is no implication that the division must be evaluated further.
 
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But isn't a fraction a division operation to begin with? Just one that remains unexpressed:

A fraction is a division expression where both dividend and divisor are integers (typically called the numerator and denominator), and there is no implication that the division must be evaluated further.

I agree. The clue is that the graphical presentation shows that 1/3 is grouped together. Writing 9 - 3:1/3 +1 (':' is the norwegian symbol for division) wouldn't change the problem. Methinks.

pibbur who observes that he's spent the afternoon writing about mathematics in stead of playing games, but is undecided when it comes to regretting that or not.
 
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But isn't a fraction a division operation to begin with? Just one that remains unexpressed:

A fraction is a division expression where both dividend and divisor are integers (typically called the numerator and denominator), and there is no implication that the division must be evaluated further.

That definition explains the point. A fraction is a way of expressing a number, but there is no implication that the division is to be evaluated further. In the context of the problem at hand, that's significant when considering the order of operations - there is no operation to be performed on "one third"; it is treated just like the other numbers, rather than one of the calculations.
 
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I would say the real problem at hand is translating the graphical representation to an ascii representation of a formula. You have to use parentheses to ensure the correct order of operations. Or postfix notation (have I mentioned that before?)

pibbur who thinks that postfix notation should come naturally to germans.
 
Just to clarify what I mean. The video portrays the expression like this:

9 - 3 ➗ ⅓ + 1

What I'm getting at, is that the way we decide on the implicit grouping is by the presence of the way "one over three" is written. When you typeset vertically with a horizontal dividing line, you imply a fraction, which then essentially is promoted in the order as if it had parenthesis around it. (Because, as I understand it, it represents a number, to be computed before the rest of the calculation.) It is treated differently than the division sign.

This is not really a maths problem as such, more a logical question of how to interpret potentially ambiguous notation.
 
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You do remember, that Once Upon a Time (though not in a galaxy far, far away), I was a High School Maths teacher!! :)

Did the invention of Roman Numerals make it easier for you or just confuse you?
 
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Roman numerals are simple to work with. Consider, the RN for 10 is X . Now, if we want to find half of that, we simply wipe off the bottom half of X and we are left with V which is the RN for 5!! See how easy this all is!!!! :)
 
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What has James Bond's boss got to do with Roman Numerals?!! :p
 
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What has James Bond's boss got to do with Roman Numerals?!! :p

Agent 007? Nothing. There are no roman numerals for zero.

pibbur who notices that due to the same limitation, roman numerals cant be used in binary and therefore are not suited for computing.
 
So did you all decide on the answer ?

Yes. There are actually 2 different problems. The solution to the problem as presented in the OP is 9. For the problem as it's shown in the movie, the answer is 1.

pibbur
 
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