this post was submitted on 23 Aug 2023
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[–] [email protected] 70 points 1 year ago

These adhd memes are made like horoscopes. They fit everybody.

[–] [email protected] 33 points 1 year ago (1 children)

I find this method is far faster for quick calculation of large numbers off hand. Or at least estimation. Choose a close round number you do know the maths for, then just add or subtract the relevant parts to get it to true.

[–] [email protected] 8 points 1 year ago
[–] [email protected] 32 points 1 year ago (2 children)

I do not have adhd. I do not have adhd. I do not have adhd.

I do math like that in my head

I do not have adhd.

[–] [email protected] 15 points 1 year ago* (last edited 1 year ago)

This is not necessarily an indication of ADHD. Being said, neurodivergence could lead people to attempting new solutions to tasks that they have never been taught, so it's not like there's no correlation. There's just no direct causation here.

Being said, this is a fantastic mental math shortcut, one that I wish would get taught more. Works for adding, subtracting, hell even multiplying and dividing. 16 × 20 is 20 more than 15 × 20, which is 300 + 20 = 320. Or perhaps you could say that 16 × 20 is 16 × 10 × 2 = 160 × 2 = 320. There are so many ways to break large numbers down into smaller, more manageable numbers for arithmetic, makes mental math a hell of a lot easier. And you can impress people with the ability to multiply large numbers in your head if you get good at it.

57 × 41 is 57 more than 57 × 40, which is (7×40) more than 50×40. Well, 50×40 is 2,000, so 57×41 = 2,000 + (7×40) + 57 = 2,000 + 280 + 57 = 2,280 + 57 = 2,337. Admittedly that took me a minute and I did originally get 2,327, but you can see the process.

[–] [email protected] 14 points 1 year ago (2 children)

I joined lemmy. Two months later I'm seriously considering getting tested...

[–] [email protected] 8 points 1 year ago

It's just people with ADHD doing things they think only people with ADHD do... No, it's normal.

[–] [email protected] 2 points 1 year ago

If the symptoms you identify with have you struggle in life, then definitely get tested. Even if not, it's still nice to know.

[–] [email protected] 25 points 1 year ago

this is NOT adhd! this is how many were taught at school, and also just sensible

[–] [email protected] 24 points 1 year ago (1 children)

I go like 7+3 = 10, 10+3 = 13

[–] [email protected] 4 points 1 year ago
[–] [email protected] 15 points 1 year ago (1 children)

Look I have adhd I'm quirky. Don't use something people struggle with as a quirky trait.

[–] [email protected] 4 points 1 year ago

But what if I wanna shitpost about my ADHD?

(don't worry I know what you mean and yeah that post applies to everyone)

[–] [email protected] 13 points 1 year ago

This is not unique to ADHD

[–] [email protected] 10 points 1 year ago (1 children)

Or: To get to 10 from 7, you need 3.6 - 3 = 3, and then 10 + 3 = 13

[–] [email protected] 2 points 1 year ago

This is what my brain does and I don't have ADHD.

[–] [email protected] 9 points 1 year ago

I split 6 as 3+3 and I know that 7+3=10 add 3, now youve got 13.

speed math

[–] [email protected] 9 points 1 year ago (1 children)

Divide by 5? Oh you mean double it and shift the decimal

[–] [email protected] 2 points 1 year ago

Good idea. I always look for the nearest dividable number

[–] [email protected] 9 points 1 year ago

That’s just a normal shortcut for mental math. Break your problem into simpler problems then combine, in this case if one wants to know 7+6 this is being turned from 7+7=14, an easy problem to remember, into (7-1)+7=14-1=13.

That doesn’t feel exactly right as it’s not exactly the way you think about it, but words can’t describe such inferences of thought other than to call them what they are which is not exactly how one’s thoughts reflect them.

[–] [email protected] 5 points 1 year ago

that's literally how i did it before reading the rest. also i don't have adhd

[–] [email protected] 4 points 1 year ago

i think about how the shape of 6 fits in 7 to make 13

[–] [email protected] 3 points 1 year ago

That how i do it and i don't even have ADHD

[–] [email protected] 2 points 1 year ago
[–] [email protected] 2 points 1 year ago

7+6 = (5+5) + (2+1) = 10+3 = 13