They could and perhaps should have answered: "There's no meaningful average..." etc. and expanded their answer with an explanation about different types of vacancy taking different times to fill, and some recruitment campaigns being 'one-off' pitches to a single candidate for a single post which, by definition, could have no meaningful statistical metadata.

Another point is that the arithmetic mean is meaningless in this type of data set, and a modal definition of the 'average' is far more useful:

"Vacancies can take anything between three days and three months to fill, but we have found that nearly half are filled in six to eight weeks; there is a 'mode' or peak at seven weeks that represents the response lag, interview shortlisting and acceptance-processing, plus the common one-month notice period for recruiting staff from rival companies. A secondary peak exists at sixteen weeks, as any vacancy unfilled after ten weeks is reappraised, and readvertised with a higher publicity budget and, if necessary, with a higher salary."

Which means that those hypothetical figures have two 'modes' for you to use as an average, a meaningless mean, and a median of five years between the one job they filled on the day with a phone call, and the vacancy they're still advertising since the last audio-typist with relevant experience in the fish-curing and smoking industry resigned in 1997.