I’m not too well up in these things, but I read that a winter-themed Lottery had to be withdrawn. Purchasers were offered a prize if their ticket showed a temperature less than -8°C. People got very upset, complained to Trading Standards, threatened lawsuits, etc when their -6° ticket didn’t win a prize. “6 is lower than 8, so -6° must be lower than -8°” was a typical response.
A few days after reading this I came across a similar story from 15 years ago. I’d written it up for ‘Mathematics Teaching’ at the time and completely forgotten about it. By the way, just to avoid possible confusion, I suppose I’d better mention that in the UK ‘vet’ refers to a veterinary surgeon rather than someone who’s seen service with the armed forces.
I’d been waiting for ages behind the woman in front of me at the vet’s. At least at the doctor’s people tend to be telling the receptionist of their own problems; at the vet’s they need to talk about a couple of dogs, the cat, some rabbits, the budgie and the guinea pig as well!
Eventually she said, “There’s just one more thing … I’ve got to inject doses from 0.5 ml decreasing to 0.13 ml. But I don’t understand: 13 is more than 5, so the doses will get bigger! The instructions must be wrong.”
The receptionist peered at the instructions. “Yes, you’re right,” she said. “Hmm. I know, I’ll get the nurse and we’ll ask her.”
The nurse arrived and had the problem explained. “Yes, you’re right,” she said. “Hmm. I know, I’ll get the vet.”
Now, our cat has been undergoing a whole range of treatments in recent weeks, so I was getting pretty worried about the way the conversation was going.
I’ve always said that one of the great skills in teaching is not intervening and letting people sort their own problems out, but knowing when to stop not intervening is perhaps even more important. So I decided it was time that I stopped being a part of the furniture and gave three people an impromptu lesson in decimals – after all, the graduations on a syringe are simply another number line. I’m not sure how much understanding there was, but everyone was not only surprised but grateful and I left behind an assortment of pieces of paper and syringes with new lines on them.
Not surprisingly, I left the vet’s deep in thought. There was also some relief. We’ve lived in Tring for 35 years now and I regularly bump into former pupils. At least none of the people at the vet’s said, “Hello, Mr Parr. You were my maths teacher!”