I haven't had much to say recently, but I think it's worth mentioning this:
Yesterday we went to the second-hand bookstore to buy second-hand books. Being part of the local library, the store has volunteers working there. The young woman personning the cash box (there's no automatic till) looked to be about 17 or 18, but I wouldn't be surprised to hear she was actually 15. Whatever. Hardbacks are $1, paperbacks are 50c and some more sought-after books have prices in round dollars on a special price tag.
We got a bunch of books and the girl added the pile up to $9.50 in her head. We gave her a twenty dollar bill. She said (and I am not making this up), "If it comes to $9.50 and you gave me $20, how much change do I give you?"
SO was speechless and withdrew from the fray. I said, in my trying to be helpful manner, "Add 50c and that's ten dollars, then add ten dollars to that and it comes to twenty. So the change is $10.50."
I knew she could add - she'd just calculated the price - but nevertheless this seemed to go over her head. She looked at me as if I'd just done some clever trick in Vedic Mathematics. But she gave us the $10.50. On the way out SO said, "How do you know we were telling the truth?"
She smiled enigmatically, like the eternal sphinx, only with less facility in math.