In Japan, the order of multiplication is discussed online.
How much does it cost to buy five apples for 50 yen each?
At school, 50x5 = 250 is correct, and writing 5x50 = 250 is incorrect.
Many mathematicians say that the order of multiplication is meaningless, but some school teachers do not change their mindset.
@mayuutann This is a horrible thing to do. Japan just lost generations worth of mathematicans with this because there are actually a bunch of kids good in math what make leisure from experimenting with their knowledge making ways to themselves to build new approaches.
This is such a wasted potential
Albert Einstein was actually a kid like this as I learned from his biography. He started playing and then mastering math and wondering about the world's rules in a young age and actually getting terrible qualities in a punishing school system.
@RealPurrplenekoboi >Japan just lost generations worth of mathematicans
Yeah, I think so, too.
Yeah, I respect Einstein too.
@mayuutann Anyone who considers themselves to be a mathematician should be aware that multiplication is, by definition, commutative. As such, there's no difference whether you write the one or the other factor first.
And if they were to expect people to correctly categorize by multiplier and multiplicand, they should only allow 5 ⋅ 50, since the multiplication is defined as 𝑚𝑢𝑙𝑡𝑖𝑝𝑙𝑖𝑒𝑟 ⋅ 𝑚𝑢𝑙𝑡𝑖𝑝𝑙𝑖𝑐𝑎𝑛𝑑, whereas the first denotes the count and the second one the value being multiplied.
@mayuutann Then, again, the order varies by culture, according to Wikipedia. So it might actually be correct in Japan to use 𝑚𝑢𝑙𝑡𝑖𝑝𝑙𝑖𝑐𝑎𝑛𝑑 ⋅ 𝑚𝑢𝑙𝑡𝑖𝑝𝑙𝑖𝑒𝑟...
@mezzodrinker Yeah, I know that the order varies by culture. Is it wrong if you write the other way in your country, too?
@mayuutann Honestly, I'm pretty sure that teachers over here couldn't care less. They would certainly teach it in a specific way (the 𝑚𝑢𝑙𝑡𝑖𝑝𝑙𝑖𝑒𝑟 ⋅ 𝑚𝑢𝑙𝑡𝑖𝑝𝑙𝑖𝑐𝑎𝑛𝑑 order, if I recall correctly) but if you opt to do it differently, they will probably not mind.
Or at least I don't recall this ever being a topic of discussions back when I was at school.
@mezzodrinker good school(good country)!!
@mayuutann Yeah; I heard that Japan is a lot more traditional and disciplined about education.
@mezzodrinker There are many rules that are not essential.
@mayuutann Wow. That's a great way to stopping the kids from thinking logically and understanding what multiplication really is, on a fundamental level.
@mayuutann But order of addition does not matter ?
@snowyfox maybe no. At least I've never heard that. maybe some teachers mind only order of multiplication. 🤔
@mayuutann 面し 🤔
@snowyfox yes, 面白い.
@snowyfox I googled this just now. There was!!
@shpuld They only do that on primary school. But people worry about that children will hate math. Because it ’s not wrong, but it ’s wrong.
@mayuutann It happened in Thailand too. 😰
@veer66 Oh, really!? 😅
@mayuutann Yes 😿
@quad I see. 😅
@quad Ahh, he isn't my teacher. This is a discussion that is currently a hot topic in Japan. 😅
@brad yes. Perhaps the teachers who care about the order is to let them do what they taught.
@mayuutann IIRC in Japan you're not allowed to prove your superior wrong, so I'm not surprised.
I mean both have good reasons.
One the one hand: Multiplication within the complex numbers is commutative and therefore the result doesn't change. So the order doesn't matter.
On the other hand: There are many other operators and structures on which multiplication is not commutative (e.g. matrix-matrix multiplication).
Of course for just multiplying with "normal" numbers it's fine to ignore order but in a strict technical sense it doesn't, it just doesn't change the result.
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