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?
0 Boosts
0 Likes
@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.
14, 28, 40, 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.
@futurebird
I do 7x7 +8, so I voted via other math
@futurebird 56 instantly, but I had Lucky Seven Sampson help me learn it
@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.
@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 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.
@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.