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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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 I always know it's 42 because that is the answer to life, the universe and everything.
All other multiplication challenges are a combination of all four listed answers
@futurebird is it relevant that I though "six seven" even though I'm a millenial? and this one, I do take the result from memory - though I had to reconstruct it from 7*5 (memory) + 7 to reassure myself
@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 :-D
@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 😅
@futurebird Good question. Also, what is the answer to the ultimate question of life, the universe, and everything?
@futurebird Ah you edited. Now I look like an idiot. It was bad enough just being one.
I thought about leaving it, but it seemed too confusing.
Look at the edit history if you want a laugh.
@futurebird that's the mistake the lab rats made when they built the earth
@futurebird@sauropods.win ...56?
I will edit it because it's confusing and the human equivalent of data poisoning to leave it as it is.
@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.