3 ms·
I don't know if it qualifies as a "mathematical coincidence" or not, but I find it amusing to demonstrate to kids that you can multiply 142,857 by 1, 2, 3, etc.
by wastholm 5y ago
I don't know if it qualifies as a "mathematical coincidence" or not, but I find it amusing to demonstrate to kids that you can multiply 142,857 by 1, 2, 3, etc., and the result is always a number with the same digits but in a different order:
2 × 142,857 = 285,714
3 × 142,587 = 428,571
4 × 142,587 = 571,428
Etc. But then, suddenly:
7 × 142,857 = 999,999
- carrolldunham 5y agoSome kids might love that but I wonder if it's also the kind of thing that makes many kids resent math and ask why do we have to learn this. Since its just like nerd party trick that reveals nothing about the world and in fact makes the world especially math, seem even more impenetrable.
- xtiansimon 5y agoYou’re not wrong. The difference (and this does not apply here in an open forum) must be the quality of teaching. Strange math tricks by themselves are empty calories.
- captn3m0 5y agoThere's actually some interesting math behind it: https://en.wikipedia.org/wiki/Cyclic_number https://en.wikipedia.org/wiki/Cyclic_number, https://www.youtube.com/watch?v=WUlaUalgxqI https://www.youtube.com/watch?v=WUlaUalgxqI (Numberphile)
- deleted 5y ago[deleted]