ah this has been asked before on answerbank, and I cannot remember the answer given then, but I do know
that in the 60's a lady would not have got into the Ritz wearing trousers/slacks
in the early 60s ladies wearing a trouser suit were not admitted into up town restaurants/ hotel lobbies etc.
gradually things changed after one or two more enterprising "ladettes" just removed the trousers in front of a full restaurant and walked in the jacket up to their bum.