In the UK, things are metric-ish. In the mid-'70s there was a government programme for metrication. It was not popular, and there were exceptions and/or 'accommodations' (for example, pubs still have pint glasses, but the standard contents are measured in ml). It's only recently that all petrol stations sell by the litre. There have been a string of interim conversions: miles per gallon , kilometres per litre...
An exception was made for greengrocers, who until quite recently were permitted to sell in pounds and ounces. And as for large distances, people still talk in miles, although maps use kilometres. In the world of 'DIY' [=Do It Yourself] some objects are sold in a mixture of systems - chipboard, for example, is metric in depth and imperial in area (or the other way round, I'm not sure: it doesn't matter, because the metric equivalent is made to approximate to a very close Imperial equivalent - wood is often sold in 300 mm units [very nearly 1 foot].)
I don't know in detail about the other countries: try Metrication - Wikipedia, the free encyclopedia
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