Poll: Asking for a friend – what do you understand by "6x4"
Recently I've had an enlightening discussion with a colleague about notation in maths and computing. I don't want to "lead the witness" so I'm not going to repeat it here, but I'd like to ask about the internal understanding of individuals in this community.
What do you understand by the expression "6 x 4" ? I fully expect that I haven't covered all the possibilities, I know that self-selected polls are useless for proper statistics, I know that some people just click all the options, etc. All that not withstanding, I'd be interested to see what people think.
Thanks.
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[ 3.4 ms ] story [ 119 ms ] threadMissed you on my tour of the UK, I really should have thought of you, that was stupid of me. Write-up is here: http://jacquesmattheij.com/journeyman-project-trip-1-united-...
I read through the possible poll answers and realize I was totally missing the question.
Google also tells me that it's actually a 2by4: "He took a 2x4 to the head".
a) An Area or b) Six, four copies of
but the little automated arithmetic unit at the back of my brain keeps "shouting" 24.
If you're not working over the usual ring, though, intuition goes out the window and I think of it as "six-but-not-six blob four-but-not-four". That's because in a module sense, it is 6 (element of ring) times (arbitrary multiplication operation) 4 (element of module).
Second association - 6 wheeled vehicle, 4 wheels driven (possibly because of the recent Top Gear with the Mercedes 6x6).
I see this as an area with six units along one side and four units along the next side.
I'd read "6 x 4" as "multiply 6 by 4" which I'd see as "6 + 6 + 6 + 6" and the same as six x four.
I am not sure what you mean by "lots" or "copies".
But that term has MANY meanings - without the context (arithmetic? wood? cars? IPv6? matrix?) it's impossible to say.
Multiplication would be 6 * 4 or 6 × 4, not 6 x 4.
http://startingstrength.wikia.com/wiki/FAQ:The_Program
As a mathematician with a slight focus on algebra when I see such terms the questions that come to my mind are rather: Which ring am I working on, has it finite characteristics, is one of these numbers a ring element and the other an Element of ℤ [1]? It is always funny to see how your focus changes your perception :)
[1] For example 4 could be an element of the finite field with 5 elements GF(5). Then I would interpret 6x4 as 4+4+4+4+4+4, because 6 is not an element of GF(5) and I thus cannot plug it into the multiplication operation of GF(5).
Even after reading the poll answers none of the this-or-that options even prompt an image of a grouping. What makes algebraic notation useful is that it abstracts away the need to model the calculation further in most cases. There's no need to ponder "x lots of y or y lots of x". That's good because "lots" and "of" are more muddied. concepts than "times". My fourth grade teacher could explain "times" by giving examples of timesing. Examples of lotsing and ofing are harder to come by.
When my son started multiplying fractions, the instruction from the teacher was clear and to the point: Parents don't teach them the methods you learned.