the classic old Sophie Tucker joke is:
It was on the occasion of Ernie's eightieth birthday and in honor of the occasion he married a twenty year old girl. And he rang me up the very next day and he said to me "Soph, Soph, I have just married myself a twenty year old girl, what do you think of that". And I said to him "Ernie when I am eighty years old I shall marry myself a twenty year old boy, and let me tell you something Ernie twenty goes into eighty a hell of a lot more than eighty goes into twenty."