There's an old joke about a joiner visiting a wood yard just after the UK's "metrification."
He says to the assistant, "I need 32ft of timber."
The reply, "Sorry Sir, we're all metric now!"
So the joiner says."OK then, give me 30 mtrs."
The assistant, playing with his extending rule, replies, "Right, 30 mtrs...err.. 30 mtrs.... Hmm. That's about 32ft isn't it?"