I knew a teacher of remedial math who would run across students who didn't know which side of the period the fractions went on and which side the whole numbers.
That gets scary when handling money....
Most kids who work behind a cash register today don't have to really count...the register tells them what bills and coins to give back.
I went nuts at McDonald's in TX. I'd go in and order a double cheeseburger to go. "Do you want that on the meal? Is that for here, or to go? Anything to drink?"
One day, I just said, "Pay attention, because I'm only going to say this once: I. Want. A. Double. Cheeseburger. To. Go."
LOL!!