Green’s Dictionary of Slang

fifty and a ten n.

[the charge is $50 for services plus $10 per hour for a room]

(US Und.) an act of intercourse with a prostitute (cf. five and two n.).

Show quotations
[US]W.T. Vollmann Royal Family 451: A fifty-and-ten [fn. Fifty dollars for the ‘flatback’ and ten dollars for an hour in the room].