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?
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@futurebird Edits aside, it's funny how to me 6*7 → 42 at once but 7*6 I need to reorder into 6*7, and same for 8*7 → 56 and 7*8 (note how my "at once" answers don't always have the smaller factor first; it's almost certainly auditory memory).
Yeah, that's how I tried memorizing them, by "chanting". And it's also why I have to "translate" it to Spanish, since I never learned the tables in English. I wish they had bothered to teach us by logic, as I've seen in some other replies. Some of it I've applied by myself over the years, but it was a "painful" self-teaching. I hope they teach it differently now.
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@futurebird Numbers below about 200 form a grid of products in my head because I've been thinking about number theory and discrete factorization for nearly 40 years, so for me 7*8 being 56 is just like, duh, what else would it be.
Similar. I describe it as "I have a lot of friends among the small integers'.
Like, 56 just falls apart into an 8 and a 7, and those line up in formation to display 2^3•7. Numbers dance in my brain.
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@futurebird I remember learning my times tables as a kid. I still have the desk that I learned them at
Some of that has faded - for some reason I always stumble over results in the 40-60 range. So for this one (7*8) I would probably guess 56 or thereabouts, then check my work knowing that 8 squared is 64.
I am similar, only I default to knowing 9x6 is 54 (because 60 - 6), and 56 is 'the other one'. A bit convoluted!
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@passenger @danielaKay @kbm0 @futurebird
Most multiplication tables go up to 12 × 12 regardless of regional measurement systems. There is nothing inherently special about 12 in the imperial system (or whatever non-metric is called). Most clocks go up to 12 and people often refer to dozens.@sloanlance @passenger @danielaKay @kbm0 @futurebird
also learned muitiplication tables to 12 (in England) but was taught nearly exclusively in metric in school (but knowing the 12 times table is at least useful for when you encounter situations where folk are still working in Imperial units (still happens too often with interior design and planning, and also if I'm reading my books about oldtimer British cars and their maintenance)
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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?
@futurebird
7×7, +7 -
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?
My method. I just know 7x7 is 49. I then add 7.
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@futurebird 7*7=49 + 7= 56
Glad I am not the only one!
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@futurebird We spent ages learning "times tables" by rote up to 12 (a hangover from the imperial measurement system), so in principle the answer to any small multiplication just springs to mind. Strangely some combinations seem to be unusually tricky to remember, and 7*6 is one of them. Whereas 7*8 is much easier.
@kbm0 @futurebird yeah I still remember the Popsicle stick packets and being paired up to quiz each other. Basically flash cards, but wood. Not sure how standard that was.
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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?
@futurebird When I was young and learning multiplication tables, I had trouble with 8 * 7. Mom told me to turn it around, to 7 * 8, and after that I had no problem.
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I am similar, only I default to knowing 9x6 is 54 (because 60 - 6), and 56 is 'the other one'. A bit convoluted!
@suearcher @futurebird Come to think of it, those two products are the ones that always make me second guess myself. But I always get the 9 times table right becasue of that handy rule that the digits add to 9, and the first digit is one less than the other number. A little more thinking involved there than just memorizing the result, though
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@MichaelPorter @futurebird I liked the fact that the 9-bys were a palindrome: 18 81, 27 72, 36 63, 45 54.
@ELS @futurebird In all my years I must have noticed that, but it feels new to me today... Yes, nice!
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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?
That's my nemesis! I was expected to learn times-tables by rote but 7*8 would never stick.
I HATE it
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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?
@futurebird 7*8 = 5*8+2*8 = 40+16 = 56
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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?
@futurebird
I still tell left from right based on where the windows were in a grade school classroom.This is also how I tell debits from credits.
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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?
@futurebird@sauropods.win I’ve got it memorised, but it takes more effort to recall than other multiples, and I often second-guess myself. I wonder what it is about this multiplication that confuses human brains.
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@oddtail The Answer is always 42. https://hitchhikers.fandom.com/wiki/42
@isotope239 @oddtail
"Six by nine. Forty two."
"That's it. That's all there is."
"I always thought something was fundamentally wrong with the universe." -
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?
@futurebird I had tables memorized until calculators came along. I was crew treasurer of a tree planting crew in 1979, and once I got that little box in my hand, I forgot everything arithmetical except data entry
. Away from tech, I get by on fingers and counting by tens. 
Algebra is actually a little easier ... I was an English major and realized early on that all complete sentences are formulae, and the enthymemes used for business and political enclosure are just formulae with hidden variables. It's a shell game and we the public are just rubes (in their eyes) that can't do math. -
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?
I think to myself "5, 6, 7, 8" and then I remember "56 = 7 x 8".
Why is that one so hard to learn though! Every other times-table ingredient went into my head much easier than that one.
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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?
@futurebird@sauropods.win my “other”: i usually get it instantly, but sometimes either don’t get it immediately, or get another number (usually 54) immediately with a sense of doubt, or just have an anxiety about it. In those cases, I go from 6x8, which was my favorite times-table entry because it rhymed and had a pleasant rhythm.
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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?
@futurebird thanks to the early 80s obsession with times able memorisation, that's locked in as an instant response.
But I also have a couple of maths degrees, so can 'play' with the numbers in my head, using other facts and 'checking' my own memory.
Like 7*7 is 49, + 7 and yup, 56.
Or as others have commented, (7*2)*4 or (7*4)*2 also help.
Or 60 = 15 * 4, and 15 is 14+1 = 7*2+1, so 60-4 works too.
I basically never assume my memory is correct, I always error correct/sense check!
