I went to work one day about 30 years ago and someone shouted he's here! I said what's the problem? How many fluid ounces are there in a litre? No one in the kitchen knew, and I was a cellarman. Shortly before they'd had an argument as to whether there two or three feet in a yard.
I found one of my school exercise books from about '64 (I was 10) with sums in pounds, shillings, pence and farthings - miles, furlongs, chains, rods, yards, feet and inches - and even gallons, pecks and bushels. Metric is rather simpler.