this post was submitted on 23 Aug 2025
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So for context, I went to first grade in mainland China before immigrating to the United States, in China, they teach kids this weird trick that's basically like reciting a "poem" thing, which I didn't remember what it was called until I recently googled it. Its apparantly called the "九九乘法口诀表" or 9x9 Song / "The Nine-nine song" (Wikipedia article: https://en.wikipedia.org/wiki/Chinese_multiplication_table#The_Nine-nine_song_text_in_Chinese).

So like... in 2nd grade, for which I was in the US, multiplication was very easy for me, well... at least up to 10x10. Like idk how to explain it to someone who's doesn't speak a variant of Chinese, and even the rhythm only works for me in Mandarin somehow, when I try to use Cantonese, which is the language I speak at home in the US, I cannot replicate the rhythm to make thay thing work, this "Poem"/"Song" is only available to me in Mandarin, like when I think about multiplying together any 2 single digit number, I instictively use the "九九乘法口诀表".

Like its goes from 1x1 then next lines are 1x2, 2x2, then next are 1x3, 2x3, 3x3, then its 1x4, 2x4, 3x4, 4x4, etc... you get the idea, mutiples of 1, then 2, then 3. So if I need to multiply something by 7, I can start from the line where multiples of 7 are. Sometimes I can remember the exact phrase of it like for example 3x7, without starting from 1x7, then 2x7, then 3x7.

Like I never thought too hard about it, it kinda just became the "normal" way I do multiplication. But someone asked a question on Lemmy about reading analog clocks and I probably didn't answer their question correctly but that was when I kinda was like: oh wow I forgot that my way of multiplication is probably different from everyone else in the west.

Like if you told me to teach a English-Only speaker on how to do multiplication tables, I... um... I don't know how I would teach that, the "九九乘法口诀表" doesn't have the rhythm in English so I doubt converting the it to English would work.

Like even though I speak English as my primary language now, and I barely have any fluency in Mandarin or even Cantonese which I speak at home (and never learned any vocabulary beyond the basics), the "九九乘法口诀表" multiplication thing is always done in mandarin somehow, like its always been stuck in my brain even after all these years in the US.

TLDR answer to my own question. I do it using "九九乘法口诀表" which takes me 1-2 seconds to recall a specific line, so basically, anything up to 10x10 takes about 2 seconds for my brsin to process, 11x11x to 12x12 takes about 5-10 seconds, anything bigger and I just giveup using my brain and pull out a calculator. I memorized 10x10 since first grade, then 12x12 probably by like 2nd grade or maybe first half of 3rd grade.

How do y'all do it, is it easy or hard?

Edit: Okay so the best way for me to explain "九九乘法口诀表" is that: Think of PEMDAS (order of operations), but its for the entire multiplication up to 9x9.

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[–] meekah@lemmy.world 1 points 18 minutes ago

we just went to 10x10, and I think we did that in like 2nd grade. so like 8yo. we just had to straight up memorize it, no helpful song or anything. We did it in sections though, so one day we were supposed to memorize 1x1 to 1x10, another day 2x1 to 2x10 etc.

I can remember 11x11 because it is annoyingly 121 not 111, and 12x12 is 144 which I find kinda easy to remember because of gaming monitors using 144hz (I don't get why my brain makes those kinda associations, it just works for me idk). 11x12 is weird because it is the first multiplication where my brain starts picking it apart like 11x12 = (10x12) + (1x12) = 120 + 12 = 132

[–] tiredofsametab@fedia.io 3 points 2 hours ago (1 children)

Rural US in the 1980s and we learnt it starting at I think like 8-9 years old. At the time 9x9 was all we learnt and we were just expected to memorize our "times tables". I don't recall any song or anything.

[–] innermachine@lemmy.world 2 points 28 minutes ago

I was born in 97, also expected to just "memorize" the tables. I never did, and despite my teacher in 3rd grade insisting we would never have a calculator on us at all times, I do in fact have a calculator (phone) in my pockets at all time to do menial math for me.

[–] Treczoks@lemmy.world 2 points 4 hours ago (1 children)

As long as you work with decimal numbers, there is no need to actually go beyond 10x10. Heck, even 9x9 would suffice, as times ten is just adding the zero. Anything else is derived from that.

[–] ayyy@sh.itjust.works 1 points 3 hours ago (1 children)

Have you ever used a clock before? I don’t want to assume how you tell time.

[–] Treczoks@lemmy.world 2 points 3 hours ago (1 children)

You need multiplication tables to read a clock? Interesting.

[–] megane_kun@lemmy.zip 1 points 3 hours ago* (last edited 3 hours ago) (2 children)

Analog clocks.

If the hour hand is pointing just past 1, and the minutes hand is very near 8, what time is the clock showing?

answerIt's 1:40

Now, ofc, it's becoming somewhat of a lost art, with the increasing prevalence of digital clock displays, so, yeah. Personally, I just developed an intuition for it, having grown up in a time when digital clock displays are rare, and analog clocks are commonplace.


EDIT/PS:

Actually, even in that case, reading off the minutes hand off an analog clock doesn't involve the times table for 12, so your original claim holds.

[–] Treczoks@lemmy.world 1 points 3 hours ago (1 children)

And now explain to me why you need your multiplication tables go to 12x12 instead of 10x10 just to multiply 8x5.

[–] megane_kun@lemmy.zip 1 points 2 hours ago

Sorry, I added it in the edit.

Actually, even in that case, reading off the minutes hand off an analog clock doesn’t involve the times table for 12, so your original claim holds.

[–] smiletolerantly@awful.systems 1 points 3 hours ago (1 children)

Sorry, but: where in that is multiplication involved?

[–] megane_kun@lemmy.zip 1 points 2 hours ago (1 children)

Reading off the minutes from where the minute hand is pointed. If the minute hand is pointed at 8, you'd have to multiply 8 by 5 to get 40.

[–] smiletolerantly@awful.systems 2 points 2 hours ago* (last edited 2 hours ago) (1 children)

And if it's pointed to 37, a prime number? Do you have to have your tables memorized up to 37x37 to be able to read that?

It's knowing how to count, at best. But out of curiosity, do you really go "long pointer at 8, 8x5=40" internally when reading the clock?

I'd imagine most people would just go "40".

Case in point: in school, we learned how to read a clock before we learned anything at all about multiplication.

[–] megane_kun@lemmy.zip 1 points 50 minutes ago

I haven't seen a "37" in an analog clock.

There's a 7, there's 8, and there are four spaces (which may or may not be marked) in between them.

Now, to the main topic:

But out of curiosity, do you really go “long pointer at 8, 8x5=40” internally when reading the clock?

No. But that's because due to experience and exposure to analog clocks all my life—which, again, is not something that should be assumed nowadays. When I was taught how to read analog clocks (preschool or very early in primary school, IIRC—so, yes, before I was taught multiplication), I was told to "count by fives". Hence: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55 and 00.

Now, when we were taught the multiplication table for 5 (maybe it's just my teacher) we revisited how to read off minutes from the clock (digital displays are still rare back then).

[–] Forester@pawb.social 5 points 6 hours ago* (last edited 6 hours ago) (1 children)

American I think by 4th grade we had to know up to 12 x12

For me I memorized all the self multiples then would subtract or add mentally

Ie 5 X 7 =? Well 5X5= 25 And 5X2=10

so 5X7 =35

So half route memorization half transative properties of multiplication

[–] thermal_shock@lemmy.world 1 points 3 hours ago

This tracks for me too, around 4th or 5th we memorized 15x15. I don't remember them all now, but I can get it with a few seconds of thinking/doing it in my head.

[–] Tollana1234567@lemmy.today 2 points 6 hours ago

3rd grade, it was easier to do algebra because of it, then do arithmetic.

[–] njm1314@lemmy.world 2 points 6 hours ago

I think they start doing it in second grade but I'm not positive on that.

[–] megane_kun@lemmy.zip 2 points 7 hours ago

I was only taught up to 10×10 in primary school, and learned mostly by rote (and also, "skip counting"). I've also heard of some techniques like matching fingers to do one-digit multiplication, but I never really learned how to do that. By that point, I've mostly memorized the multiplication table up to 10.

For 11, it's absurdly easy once I got the technique, just double the number (up until 9). 11×10 is just appending a zero, and 11×11 I just memorized.

For 12, I actually didn't bother that much? 12×N = 10×N + 2×N. Thus, 12×11 = 110 + 24 = 134 and 12×12 = 120 + 24 = 144 (which I got memorized for some reason).

I still have some trouble with the 6, 7, and sometimes 8 multiplication tables, but I can usually recall it with a bit of effort. Not much, but not without some awkward pause.

Now, for how I got to memorize it. The process was hard at first. I had to recite the multiplication tables as a drill almost everyday. We also had long quizzes (hundred items) of one-digit multiplication and two-digit division (by the fourth grade), so there's an incentive to memorize the tables if only to be able to get through those quizzes with minimal pain. There's also a social stigma for being the last person to get done with those quizzes (or worse, running out of time), so there's that pressure too.

[–] dil@lemmy.zip 3 points 9 hours ago

I just memorized it to be the fastest and get candy, I was a fat kid, and memorizing the single digits is necessary to do math in your head? I never understood how to use my hands and i cant hold a visual that well, like 3 apples become 5 become 1 become a truck in the span of a second

[–] NorthWestWind@lemmy.world 3 points 9 hours ago

I did it in Cantonese, probably similar to the Mandarin poem.

I think my mom started making me memorize it in the last year of kindergarten (I was 5yo). By the time multiplication becomes the main topic in primary 2 (2nd grade) maths, I didn't really have much problem doing them. It was really useful to have it recited.

[–] pineapplelover@lemmy.dbzer0.com 3 points 13 hours ago

I believe in 2nd grade I memorized tables from 1-12. Practice makes you quicker with things and as I don't multiply random numbers often it will take me a couple seconds to recall the answer

[–] TeddE@lemmy.world 5 points 15 hours ago

My dad played a kind of patty-cake growing up where I practiced doing times tables in rhythm. My dad would pick the addend and set the pace, and we'd alternate left and right hand high fives while saying say multiples of four. 4 8 12 … 36 40, then we'd just switch to 7's, slightly slower pacing 7 14 20~ … if i made mistakes - 21, let's try again: 7 14 21 2…8 35 … no reprimand for error - we had a beat to keep, just take a downbeat and try again. Of course simpler numbers were taken further 3s were occasionally done out to 300, and 2s were done as fast as I could spit out the words. 5s were often the rest set, done at a basic pace.

The madlad had me polishing my 13×13s before school ever even mentioned the existence of multiplication.

[–] JusticeForPorygon@lemmy.blahaj.zone 25 points 23 hours ago (1 children)

I had the typical American experience of sitting with my dad every day for a couple weeks crying while he repeats "WHAT'S SEVEN TIMES THREE

[–] meekah@lemmy.world 4 points 19 hours ago
[–] Netux@lemmy.world 3 points 16 hours ago (1 children)

Still not memorized. 7,8,9 still involve doing some quick count by number to get the answer (or using the finger trick for 9)

[–] kaklerbitmap@lemmy.world 4 points 14 hours ago

9s are easy up to 10 because the two digits of the answer add up to 9. 18, 27, 36, 45, etc.

[–] Archangel1313@lemmy.ca 3 points 16 hours ago

Grew up in BC, Canada. We were memorizing the table all the way up to 12x12 by grade three. I don't remember there being a specific limit taught before that...only that we got introduced to multiplication in grade 1, and did more in grade 2. But, grade 3 was when we needed to know the whole thing.

[–] starlinguk@lemmy.world 13 points 23 hours ago

I memorized them. 'I didn't feel like it' was not an option. We did times tables every morning, everyone knew them after a while.

[–] PlzGivHugs@sh.itjust.works 24 points 1 day ago (6 children)

I want to say we were supposed to learn them in second grade in Canada, but I personally never did. My memory isn't good enough, so to this day, I just work it out in my head. For small numbers like 1-12, its easy enough to break it down to smaller parts and solve quickly anyway.

[–] TheEntity@lemmy.world 9 points 1 day ago (9 children)

Same here. Nobody ever noticed, so why even bother with memorizing if I can calculate it fast enough.

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[–] Jumi@lemmy.world 2 points 16 hours ago

Most I just know instantly since I need them for work from time to time and just memorising them is quicker than a calculator.

[–] CaptPretentious@lemmy.world 2 points 16 hours ago

3rd grade. Was pretty easy. Also helped I had nearly a mile walk to school (and back) with no distractions (didn't think I had even a Walkman yet) so I was able to practice whatever. Math was easiest because it was right or wrong and it was easy to pick 2 random numbers.

[–] antlion@lemmy.dbzer0.com 2 points 16 hours ago

Memorized in 6th grade. An optional goal in class to complete the “60 second sweep”. It only went up to 9, but we had to get in front of the class and do them all in 60 seconds.

[–] zxqwas@lemmy.world 3 points 19 hours ago

Mid 5th grade for up to 10. I was slow at it because I did not like the rote learning.

Then a few years later I memorized some 50 digits of pi because why not. I don't know why I found that amusing.

[–] iii@mander.xyz 12 points 1 day ago

We stopped at 10x10. I'm still bad at them!

[–] NeatNit@discuss.tchncs.de 10 points 1 day ago

I never did. I was never interested in memorization, when I already had ways to do multiplication slowly using basic principles.

I still pull out a calculator for nearly every calculation. I can't do 6×7 instantly, if I don't have a calculator I'd take my time and break it down to something that I can solve. And sometimes I get it wrong.

That's never stopped me though. I'm studying electrical engineering and computer science, both of which are very math-heavy, and I get top grades. Most exams allow a calculator anyway.

That's said, I don't recommend this way of life. I think the multiplication table is genuinely really useful to have memorized. I'm a bit of an idiot for never doing that.

[–] jordanlund@lemmy.world 8 points 1 day ago (7 children)

Much easier when I learned you just take the previous number and add + whatever to it.

5 X 8 = 40
5 X 9 = 45 (40+5)
5 X 10 = 50 (45+5)
5 X 11 = 55 (50+5)
5 X 12 = 60 (55+5)

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[–] SofiaPet@lemmy.blahaj.zone 5 points 22 hours ago* (last edited 22 hours ago) (2 children)

7 was weirdly easy for me, 9 has tricks to at least 10 that can help, but the easiest was probably 2, 5, 10. How? Idk. Brute force probably.

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