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I am an accountant, literally work all day with numbers. 8+7, fine, that’s 16 minus one or 14 plus one.
8x7? Never managed to memorize the times tables so that is, well 4 7s is 14 +14, that’s 28, so 8 7s is 28 + 28, which is 40 and 16 so that’s 56.
interesting how mathes works differently for many people. because I do 8+2 to get 10. then 7-2=5, so 10+5 = 15.
Quick mafs
I understand not everyone spends that much time with numbers when they are a kid, but having liked maths (I know, I know…), I had to add up numbers enough times to recognise the pattern. So whenever I saw ghefruifghergu8+vzeru4vgbedrzvrehb7, I knew that it will end with 5, and the preceding digit will increase by one (unless it ended with 95, but enough repetitions…).
It doesn’t even take intelligence, just enough repetitions ro recognise patterns - like almost everything. The same goes for the multiplying table. 8x7 isn’t 56 because of the above (rather smart!) investigation anymore, but simply because 8x7 is 56, because it was also 56 for the previous 573482967589345 times. Powers of 2, up until 20? For the first few hundred times I had to start from scratch, but after ~100 repetitions, I ended up remembering them until 64. 2^7 was easy to calculate then, it’s just 64x2=128. And then it grew.
Don’t you just carry the 1?
1 calculator app on my phone, always.
No, it’s Carry On My Wayward Son.
I actually never learned this (terrible math skills from never learning basics)
Is that just adding 7+7 and then 1?
I was just being dumb.
But 8-7 DOES leave you with 1. And if you carry that 1…well. You get the picture. The possibilities are endless.
I can barely carry myself, don’t expect me to carry numbers.
Why would you just type 15 into your calculator?
Like semantic satiation, where you say/hear a word so much it stops making sense, is there one for numbers? Permutation satiation? Trying to do basic, easy mathematical tasks and the numbers stop making sense and begin slipping away.
I just say I’m not good at math while i look at someone in the eyes for a little while until they do the math.
In high school calc, I would do all kinds of algebra, integration, etc. and then at the end add 8 and 7 and get 13. All the time.
To this day, put 7 anywhere in my equation and I am gonna return an error. Dunno why. Remove 7, I work, give me 7, I suddenly struggle a lot.
Its like when you do the whole logic and calculations part and then forget to square root the number at the end.
I’d always forgot to change signs after multiplying
Must have been doing a lot of base-12 math?
Okay I know it’s 15, simple math, after all 8+8 is 16, you would have to be an idiot not to know that, so it’s just 1 less than that, anyways let me pull out my calculator just to check…
I don’t know what to make of this comments section. This many people really don’t have 8+7 down?
I don’t even feel superior about it, just bewildered.
For us older folk, and unfortunately, also for some younger folk that grew up in more “conservative” small towns, borrowing and fancy math trickery was the work of the devil.
We were required to memorize the addition tables as well as the multiplication tables. And even then, addition could be done on your fingers and toes so as long as you could add the big numbers like 8 & 7 together faster than the really slow kid could take off his shoes and work it the hard way, you were considered proficient at addition.
So ya, there’s a wide swath of America that just sucks at basic math.Yeah, I thought there was something more to it and am disappointed.
Maybe I just have it fresher in my head because I play a lot of Killer Sudoku. 15 pair box? That’s a 7-8 or a 6-9.
Same here. I wasn’t great before, but I’m actually super fast at anything below 45 now.
In my case, the mental math trick suggestion (make it 10 + 5) was intended as a way to build a skill using the provided, easy example. That type of mental math can be applied to much larger numbers, particularly when combined with other mental math tricks.
15
This is why learning binary is so important. In base two, the same equasion is 1000+0111=1111, now you just convert back to decimal with: 8+4+2+1= sweats and starts counting on fingers before reaching for calculator
Neat trick, now do nonary!
Right, as we all know, the most sensible way to do nonary algebra is in ternary, so we simply calculate 22+21 and convert back to nonary, and optionally decimal afterwards. So, 2 add 1 is 0, carry the 1, add it to 2 for 10, add the 2, carry the one, pad to 4 places and we have 0120, or 16 in base 9. Now to convert to decimal… removes shoes and socks
Easy, just convert to hex, 0x0F
8+7 = 8 + ( 2 + 5) = ( 8 + 2 ) + 5 = 10 + 5
Then just do the column addition (1 + 0) =1 and (0+5)=5
Thus concat(1,5) = 15
Now do it where you turn all the numbers into ones via math fuckery
8+7
11+1+1+1+1
that an 11
That would require me to make a +1 and a -1 table and I would have a real hard time knowing if I made the tables display correctly.
I am chronicly paranoid because I have had a low battery on an exam. I just type in simple math because it might be totally borked and you won’t catch it on something complex
Same. In contexts where there are a lot of already taxing elements, there is just no mental bandwidth for switching gears and doing the calculations. So calculator it is. I do find it important to hone my skills from time to time, just not to lose them.
Wait, it gets things wrong on low battery?
I can’t speak for low battery, but I can for different brands of calcs.
Back in high school majority of students had this specific model, and I had a different one. My entire answer to a question on an exam was correct, but my calculator somehow calculated different decimals to the ones from the popular model. And it was like 4th, 5th decimal or something. The asshole teacher took all of my points away on that. Meanwhile, one of her fave students forgot a very important part of the formula which made the calculation completely wrong and the teacher still gave them half the points for it. God, I hated school, lol.
It…shouldn’t. The 7-segment displays will have contrast issues, then the whole thing will stop working entirely when the battery gets too low.
All it means is I got 141 2/3 chance of winning at Sakerfice.
Why? Just take the time to do the work properly. You will get better at it, enjoy life more.
Some of us have aphantasia and can’t do maths in our head.
What does not being able to see inner images have to do with math?
I’m asking because I can’t see shit but I have no problems with doing math up to a certain point. Not in any way good at it but it doesn’t impair my memory to the point it would be a hindrance either.
Because you can’t hold two numbers in your mind simultaneously, or imagine one adding to another and the result of that. It’s probably difficult to explain if you are able to visualise things.
I can do maths on paper when I can see it on front of me. But I don’t have a mind’s eye.
I can’t see anything but I can still hold numbers (again, up to a point) in my head without any kind of problem. It’s not a memory impairment in any way, at least not for me. Then again there’s not that much research into it so I’m genuinely curious about your experience as well.
Yeah I can’t hold the numbers in my mind. It’s like i can grasp the concept of a number for a split second and then it’s gone like smoke. How do you add two numbers together in your mind? Like, what happens?
My thought exactly. I resonate with this meme but I also try to challenge myself to do math longhand on paper
oh i know that one from my cribbage days
