tycho wrote:quicksand wrote:popat wrote:So where are we on this one.Me this 13 is the collect answer.Whichever way u look at it.
Type
21-3×2+4÷2 exactly as is into the Google search box, hit Enter ...
Alternatively type
=21-3*2+4/2 into the Excel expression bar (with the equals sign)
Both evaluate to 17.
Not convinced? Enter the expression in WolframAlpha
http://www.wolframalpha.comthe site ran by Wolfram Research, the guy who invented Mathematica.
To those who insist 13, the people who programmed Excel and Google are brighter than you, and Wolfram is a certified Mathematical genius, I am not saying I am at par with them, far from it but at least I can evaluate this equation correctly ...
17 is the answer ..end of story.
If a certified mathematical genius makes a statement, then that statement is true.
Wolfram states that 21-6+2= 17. And Wolfram is a mathematical genius.
Therefore the statement 21-6+2= 17 is true.
Clearly this proof is not relying on mathematics. It relies on social postulates, that is on our judgment on a person as a mathematical genius or that he scored an A in his exams.
This argument still holds for any program made by humans.
But in essence it cannot be a proof. I say the answer is 17 because it is the consequence of a simple and 'natural' ordering procedure and as beings with limited rationality we 'should' always seek to simplify. That is conform as much as possible, with 'nature'.
I don't know where you get this social postulates stuff from,..and Wolfram didn't directly state that 21-6+2= 17 ... he made an inference engine in which the left to right rule is clearly apparent. As is also the case with Excel and Google. What I have done is similar to an author of a paper referencing a more detailed, expert focused paper. I am saying, look at these guys, and their expertise and work, and they do it this way, and their claim is probably more correct as opposed to your BODMAS theory from lower primary school. It is in essence
proof. It is normal to defer to people who know more than you, esp in a scientific issues because there is a systematic way of establishing theories and proofs,...invoking tired predicates becomes unnecessary, the credentials speak loud enough.
In any case, if I was a total moron in maths and you placed a maths professor and some guy who works as a lawyer or real state agent to puzzle a maths equation, I would probably believe the professor.