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 go “8 times 8 is 64” to verify so I guess I have some kind of mechanism with minimal memorization.
@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.
@futurebird for 7*8, 56 is memorized, but for other multiplications like 7*9, I think 70 (7*10) minus 7 = 63
@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 😂
@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.
@futurebird when I was in elementary school, our teacher started every day with handing out a piece of paper, that we folded into a grid pattern and filled in the table 1-10 across the top row and left column. And then timed our filling out the rest. It was memory training.
@futurebird I had a hard time learning the multiplication tables, especially for 7 and 8. Until I realised I didn't need them 😁. All I needed was to remember 7×8=56. For all other multiplications (up to 10), the other tables would do just fine 😆
@futurebird I just remember the words. Like a song or a poem. Math was never a favorite subject.
I'm 56 years now, so I had quite a time to learn. But I remember especially this problem to be a hard one for me when I was a child.
@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 9
So 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.
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.
@futurebird I'm too old to not have up to roughly 12x12 (though honestly more like 10x10) memorized. Those nuns at least couldn't apply corporal punishment at my school. Base 2, well that's a professional job skill.
@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 rememer, and 7*6 is one of them. Whereas 7*8 is much easier.
@futurebird I hated having to memorize times tables in elementary school. But I got fast at using the parts I did remember. So I would do 7*6 as (6*6)+6. And 8*6 as (6*6)+(2*6). So effectively I just memorized the 2, 5, 10 and square tables and derived everything else by addition and subtraction.
@futurebird
Instantly, because it was 7x8=56 was the exact calculation that I got wrong at primary school that resulted in me being made to stand up for the rest of the session.