12 ms·

According to https://en.wikipedia.org/wiki/Talk:ISO_216#Formula_looks_broken%3F https://en.wikipedia.org/wiki/Talk:ISO_216#Formula_looks_bro... the number was a

by jwilk 6y ago

According to https://en.wikipedia.org/wiki/Talk:ISO_216#Formula_looks_broken%3F https://en.wikipedia.org/wiki/Talk:ISO_216#Formula_looks_bro... the number was addead "as a fudge factor to make the formulae fit the known millimetre measurements". Yay… :-/