You have to appreciate our muddling-through ways...
However, there is a background as to why two weights were/are shown on, e.g., food packaging. The obvious one is 1 lb and 454 g.
Up to our recent change the LEGAL weight was 1 lb, with the metric being indicative. Now the LEGAL figure is the metric one.
Although I can't prove it at the moment I reckon that the reason fuel pricing changed to pence per litre was because the price was going through GBP 2 (or was it 1?) per gallon, a politically 'explosive' number. Easy side-step: charge per litre. Now that we are close to GBP 1 per LITRE how will they re-price to hide that...?...
Changing distances to km could be hugely expensive as all the road signs would have to be changed. The Irish did it, but it's a much smaller country with, I think, proportionally less traffic than the UK. Needless to say, for quite a while signs in miles and km were up at the same time.
Interestingly, the use of litres per 100 km is not used here. Occasionally one hears of miles per litre (now that IS mixed) but I think that (or km/l) makes more practical sense than the very common l/100 km.
DAS
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