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I keep reading the phrase 10 times lighter than..... or similar. This quote is current: "Plastic containers are cheaper to make and 15 times lighter than glass ones, says Dairy Crest". This can not be correct usage surely?
I can take 'glass ones being 15 times heavier than plastic ones' or, though unwieldy, plastic ones are 1/15th the weight of plastic (ones), but 15 times lighter?
It seems popular.