Is there anything mathematically interesting about today's XKCD, https://xkcd.com/2313, "Wrong Times Table"? It's commutative, or at least no exceptions can be found. But it is *not* associative. There are 48 ways to test associativity, and it passes exactly 24 and flunks exactly 24, which is slightly interesting. None of the rows or columns is monotonic. Many rows and columns have duplicate numbers. Not all the entries are integers. There's a zero divisor.
I’m told that Burger King tried to introduce a burger with one-third of a pound, to compete with McDonald’s Quarter Pounder. But many consumers thought that the former had less meat than the latter, since 3 < 4. Cris
On May 29, 2020, at 7:48 PM, Keith F. Lynch <kfl@KeithLynch.net> wrote:
Is there anything mathematically interesting about today's XKCD, https://xkcd.com/2313, "Wrong Times Table"?
It's commutative, or at least no exceptions can be found. But it is *not* associative. There are 48 ways to test associativity, and it passes exactly 24 and flunks exactly 24, which is slightly interesting.
None of the rows or columns is monotonic. Many rows and columns have duplicate numbers. Not all the entries are integers. There's a zero divisor.
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Cris Moore moore@santafe.edu "Work as if you live in the early days of a better nation.” — Alasdair Gray
Long ago, my five year old son once observed, "the reason they call it one hundred is that tenty sounds too much like twenty." On Fri, May 29, 2020 at 6:58 PM Cris Moore via math-fun < math-fun@mailman.xmission.com> wrote:
I’m told that Burger King tried to introduce a burger with one-third of a pound, to compete with McDonald’s Quarter Pounder. But many consumers thought that the former had less meat than the latter, since 3 < 4.
Cris
On May 29, 2020, at 7:48 PM, Keith F. Lynch <kfl@KeithLynch.net> wrote:
Is there anything mathematically interesting about today's XKCD, https://xkcd.com/2313, "Wrong Times Table"?
It's commutative, or at least no exceptions can be found. But it is *not* associative. There are 48 ways to test associativity, and it passes exactly 24 and flunks exactly 24, which is slightly interesting.
None of the rows or columns is monotonic. Many rows and columns have duplicate numbers. Not all the entries are integers. There's a zero divisor.
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Cris Moore moore@santafe.edu
"Work as if you live in the early days of a better nation.” — Alasdair Gray
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-- Thane Plambeck tplambeck@gmail.com http://counterwave.com/
Worth remarking that there may be more to the Burger King muddle than meets the eye. I have noticed that Joe Soap, while content to tackle measuring out 1/4 or 3/4 of a cupful, will balk at 1/3 or 2/3. Other systemic factors seem involved, besides simple confusion. Firstly, any facility with numbers generally has been learnt by rote, either in early education or incidentally via practice, on a case-by-case basis. So 3 and 4 are different animals, like cats and dogs; and scant intuition about numbers in general is available to process unfamiliar species. Secondly, human brains do appear to be equipped with some form of hard-wired binary logic & arithmetic. Their instinctive friend-or-foe evaluation of individuals in preference to more nuanced continuous or multidimensional models is an instance; a Roman and mediaeval algorithm for multiplication implicit involving binary representation is another. Finally, habitual reliance on similar primitive models of reasoning actively inhibits the acquisition of more elaborate or appropriate ones. If it works, for chrissake don't change it! (Sorry about that, Chris!) WFL On 5/30/20, Thane Plambeck <tplambeck@gmail.com> wrote:
Long ago, my five year old son once observed, "the reason they call it one hundred is that tenty sounds too much like twenty."
On Fri, May 29, 2020 at 6:58 PM Cris Moore via math-fun < math-fun@mailman.xmission.com> wrote:
I’m told that Burger King tried to introduce a burger with one-third of a pound, to compete with McDonald’s Quarter Pounder. But many consumers thought that the former had less meat than the latter, since 3 < 4.
Cris
On May 29, 2020, at 7:48 PM, Keith F. Lynch <kfl@KeithLynch.net> wrote:
Is there anything mathematically interesting about today's XKCD, https://xkcd.com/2313, "Wrong Times Table"?
It's commutative, or at least no exceptions can be found. But it is *not* associative. There are 48 ways to test associativity, and it passes exactly 24 and flunks exactly 24, which is slightly interesting.
None of the rows or columns is monotonic. Many rows and columns have duplicate numbers. Not all the entries are integers. There's a zero divisor.
_______________________________________________ math-fun mailing list math-fun@mailman.xmission.com https://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun
Cris Moore moore@santafe.edu
"Work as if you live in the early days of a better nation.” — Alasdair Gray
_______________________________________________ math-fun mailing list math-fun@mailman.xmission.com https://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun
-- Thane Plambeck tplambeck@gmail.com http://counterwave.com/ _______________________________________________ math-fun mailing list math-fun@mailman.xmission.com https://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun
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Cris Moore -
Fred Lunnon -
Keith F. Lynch -
Thane Plambeck