Adjusting to Difference

I've lived up here back and forth between B.C. and the U.S. (mostly Point Roberts) for over 20 years, and I've pretty much learned to work with the constant need to convert things: money, distance, yard goods, dollars, temperatures whatever difference needs to be accommodated.  The temperature I'm the worst at, where mostly I just convert 0, 10 and 20 degrees C. to  32, 50, and 70 degrees F.  Any numbers in between I just estimate.  For other things, I usually have a conversion number that I just multiply by, depending upon the direction.  The money, like the temperature, changes regularly, so those are the most difficult and are more likely to just get estimated.

However, I may have reached a new level of adjusting to the need to understand difference.  Today, we were driving down to Bellingham, and shortly after we crossed the border (I wasn't driving), I made a mental note of the speed sign for cars: 70 mph.  I automatically converted it to the appropriate speed by multiplying by .8.  In Canada, I multiply kilometer speed signs by .6, but I guess I was thinking that since it was the U.S., I probably ought to use a higher number.  56 mph, I thought to myself: slow for a freeway.

This may just be the loopiness of age, but it seemed like a new level of understanding; not necessarily a better one, but at least new.