Edit: it appears that this is not exclusive to ADHD.
Posting this meme stemmed from my own efforts to explain my thought process when doing math and how it is similar to other people with ADHD doing math, while being different from every neurotypical person I'd talked to on the same subject.
While I didn't make the meme itself, instead finding it in my saves and wanting to share, I did accidentally spread misinformation that I had only backed up with personal anecdotal evidence.
I'll leave this up just so people can see the explanation below but this appears to not be ADHD related and just due to different people doing math in their heads differently...
7 is closer to 10 than 6 so we consider that 7 is really just a 10 with a size-3 hole in it and we fill that hole with 3 from the 6 giving a 10 with 3 left over which make 13.
Also not an ADHD thing.
That's my strat too. Also confused what this has to do with adhd