When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
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@futurebird
I still remember it as 8*7=56, which is easy because of the way we say numbers above 20 in Dutch.
"Eight times seven is six-and-fifty", 8 7 6 5.
@futurebird
7*8 = 7*2*2*2 = 56.
This is a useful “trick” that allows you to break down many calculations into simpler parts. 
@futurebird I usually manage to remember the small factors (2 or 3) and 5×. So 7×8 = (5×8) + (2×8). I was never very good at remembering the table, and I was glad when I understood the intuition of which known numbers I could add up/subtract.
In elementary school, I thought I was bad at maths because I just couldn't remember those numbers well, now I have a PhD in physics...
@futurebird for that sort of big math problem, I'll use the sliderule. (although since 7 times 8 would overflow, you have to use the log(7) - (log(10) - log(8)) technique to find the answer of 5.6 times ten to the something)
@futurebird
It used to be instant, but now I have to think about it. I have no instant way of checking.
Usually 8x8=64-8=56
@futurebird 7x8 was the only one under 11 that didn't just seem self-evident to 3rd-grade me, so I had to memorize it. It still doesn't have an image or feel for me the way the rest of the 0-10 times tables do...
@futurebird Because I know 7 x 7 is 49, I just add another 7. 🤷🏻♂️
@futurebird mostly directly, but sometimes by comparing it to 7*6 or 8*8
@futurebird This for me changed over the years. At first I just remembered the answer, but after not doing mental math for a while I'd forget. My first shortcut was (8 * 5) + (2 * 7) = 40, I learned from a school friend. Later I also learned (7 * 10) - (7 * 2). As I got more familiar with binary, powers of 2 became more intuitive so I also tried (8 * 😄 - 8. But these little tricks are mostly not needed, with a little practice everything comes back, and I revert to memorizing the result again.
@futurebird This one traumatized me so much I taught all 3 of my kids 'seven eights are fifty six' as a marching cadence when they were toddlers.
@futurebird I often factorize somehow and add things up. That way you get to see the numbers, and you can remember your frequently used numbers - not that I'm usually very trained. (lol *grin*)
@futurebird in elementary school you could at any time (Montessori school) take a times table challenge, and if you got everything right you got I think a stick of gum. This was a big deal to me as Mom was pretty strict about our dental health growing up so we were only allowed sugarfree gum at home 😅
also when we learned them as a class there were songs which also helped. I still remember the tune for the 3 times table song because it was catchy as hell 😂
@futurebird
8 * 5 = 40
8 * 2 = 16
Then add them.
Yes, every time.
@futurebird I have a learning disability that was never adequately addressed. I can do arithmetic only with a calculator. I have immense difficulty recalling equation strings I'm supposed to know, and I canNot conceptualize numbers in my head of more than about 5. I have aphantasia and cannot 'see' in my mind, and I actually organize most by a system of spacial relations I find difficult to explain. Oddly, I still passed Calc3 in Uni, due largely to its spacial nature and a graphing TI hehe.