Order of operations confusion
Hello All, Just thought I'd relay a rather interesting story: Last night I was having my son work-out a simple problem from a new little webapp that I coded up called "MakeItTrue" ( http://www.asymptopia.org/MakeItTrue.html ) which had 3 arbitrary variables embedded into a larger equation, and the objective is to simply choose 3 values which make a true equality of the thing.... So, the equation we were dealing with was something like: 82+b*c-51=d-13, and the thing that surprised me was that he didn't think it was legal to take 82-51 before having dealt with the b*c term ... on account of the "MyDearAuntSally..." or "BODMAS" ... or whatever acronyms they teach in school ... he had no idea that he could do that, merely because it had been driven-home in his head that multiplication must always be done first ... Well, I thought that was rather significant, so thought I'd pass it along to you all. Take care out there, -Charles -- AsymptopiaSoftware|Software@theLimit http://www.asymptopia.org
I wonder if it's really about the multiplication, or just about the reshuffling. Would he be okay rewriting 82+x-51 as 82-51+x? On Thu, Mar 5, 2009 at 11:51 AM, Charles Cossé <ccosse@gmail.com> wrote:
Hello All,
Just thought I'd relay a rather interesting story: Last night I was having my son work-out a simple problem from a new little webapp that I coded up called "MakeItTrue" ( http://www.asymptopia.org/MakeItTrue.html ) which had 3 arbitrary variables embedded into a larger equation, and the objective is to simply choose 3 values which make a true equality of the thing....
So, the equation we were dealing with was something like: 82+b*c-51=d-13, and the thing that surprised me was that he didn't think it was legal to take 82-51 before having dealt with the b*c term ... on account of the "MyDearAuntSally..." or "BODMAS" ... or whatever acronyms they teach in school ... he had no idea that he could do that, merely because it had been driven-home in his head that multiplication must always be done first ...
Well, I thought that was rather significant, so thought I'd pass it along to you all.
Take care out there,
-Charles
-- AsymptopiaSoftware|Software@theLimit http://www.asymptopia.org _______________________________________________ Edu-sig mailing list Edu-sig@python.org http://mail.python.org/mailman/listinfo/edu-sig
-- --Guido van Rossum (home page: http://www.python.org/~guido/)
2009/3/6 Charles Cossé <ccosse@gmail.com>:
82+b*c-51=d-13, and the thing that surprised me was that he didn't think it was legal to take 82-51 before having dealt with the b*c term
This relates to a programming task called a "Parsons Problem", shown to be intermediate in difficulty between the tasks of interpreting code and writing code. In a Parsons Problem you see the lines of a 5-10 line program in scrambled order, and have to put them back in the right order. In some cases there's a bit of freedom (e.g. result += 82 and result += -51 could go in either order). http://portal.acm.org/citation.cfm?id=1404520.1404532 -Steven Bird http://www.csse.unimelb.edu.au/~sb/
participants (3)
-
Charles Cossé -
Guido van Rossum -
Steven Bird