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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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 think “7 times 8 is 56” because for some reason that’s how I memorized the multiplication tables. Almost got me in trouble with the other third graders in a “multiplication bee” where I was destroying them but whispering the first part under my breath.
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Look at the edit history if you want a laugh.
Off topic, but why does Mastodon offer two things to click on if it's only been edited once?
V confusing.
@futurebird -
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 have this one specifically memorized because it’s the times table that Molly the American Girl gets wrong in one of the books and 9-year-old me was like “that will never be me, I will commit 56 to memory like it’s my home address” and so it has been ever since

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@futurebird 6*7 is 42, which I have memorized like most of the multiplications up to 12*12.
But 9*6 = 54 is one I can never remember on its own. I always go 8*6 and then add 6.
@aesthr @futurebird the 9s are easy though! Because it’s whatever the non-9 number is (6) minus 1, so 5, then make it add up to 9 (5+4=9). I have no idea why this is easier for my brain than any other addition/subtraction

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@futurebird I have the weirdest thing with this.
When I had to learn those multiplications my mom would question me for practice. I always forgot the answer to 7*8.
One day we were in the living room and the TV remote was on the table. Remember the numbers on that:
1 2 3
4 5 6
7 8 9So I saw 7 and 8 on there, and the right answer just above. It clicked in my head.
So whenever I have to multiply 7 and 8 I see a TV Remote in my head. We don't even own a TV, I havn't had one since 2001.
@johnnythan @futurebird ars memoriae
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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 for 7*8, 56 is memorized, but for other multiplications like 7*9, I think 70 (7*10) minus 7 = 63
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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 for some reason 7*8 is the most difficult pair in the multiplication table, and because this had been a topic again and again in elementary school, so I actually sort of memorised the phrase "7 times 8 is 56".
For others I might go 8 * 9 is like 8 * 10 and then subtract 8 * 1 to get 72.
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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 go “8 times 8 is 64” to verify so I guess I have some kind of mechanism with minimal memorization.
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@futurebird 6*7 is 42, which I have memorized like most of the multiplications up to 12*12.
But 9*6 = 54 is one I can never remember on its own. I always go 8*6 and then add 6.
@aesthr @futurebird funny how everyone has *one* multiplication pair that just doesn't compute

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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 we went up to 10*10 in West Germany.
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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 56 instantly, but I had Lucky Seven Sampson help me learn 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
I do 7x7 +8, so I voted via other 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?
@futurebird I work with networks a lot, so the powers of 2 are burnt into my brain at this point. 64 is 2 to the power of 6, which by powers laws is 8 squared. 7 x 8 is 8 less than 64. And this explanation took a lot longer than the process takes.
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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?
14, 28, 40, 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
8 * 5 = 40
8 * 2 = 16
Then add them.Yes, every time.
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Off topic, but why does Mastodon offer two things to click on if it's only been edited once?
V confusing.
@futurebird@BenAveling One is the pre-edit version, one is the post-edit version.
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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
14*4 -
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 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

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For certain types of multiplication... I multiply by 10 (or 100), 1000 and so forth, then subtract the smaller number.
So 7*8 becomes 70 - 2*7 (14) = 56. Obviously I don't do that with such small numbers, but it does work very well when using larger ones.
By converting the answer into two smaller and quicker to answer ones... I get to the answer quicker than some people trying to do the single way.
@Anomnomnomaly @futurebird Yes! Back when my daughter was a wee one, they hade the concept of "10-friends" in school. Memorize 1 for 9, 2 for 8, 3 for 7 and 4 for 6 (5 of couse and, 0 for 10). Thats it! One gets that memorized (backbone level) and methodology for in-head-math will pop up. Beautiful if mentors do credit kids for re-inventing math /methodologies/. I hope this is legible.
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@Anomnomnomaly @futurebird Yes! Back when my daughter was a wee one, they hade the concept of "10-friends" in school. Memorize 1 for 9, 2 for 8, 3 for 7 and 4 for 6 (5 of couse and, 0 for 10). Thats it! One gets that memorized (backbone level) and methodology for in-head-math will pop up. Beautiful if mentors do credit kids for re-inventing math /methodologies/. I hope this is legible.
@Anomnomnomaly @futurebird In other words: we/i claim that it is better NOT to memorize the table of multiplication in favour of thought trains. That helps with understanding. As opposed to using an LLM btw.