The word(s) "fifty" appears 2 time(s) in 2 verse(s) in Quran in Mohsin Khan translation.

(1) And indeed We sent Nuh (Noah) to his people, and he stayed among them a thousand years less fifty years [inviting them to believe in the Oneness of Allah (Monotheism), and discard the false gods and other deities]; and the Deluge overtook them while they were Zalimun (wrong-doers, polytheists, disbelievers).

(2) The angels and the Ruh [Jibril (Gabriel)] ascend to Him in a Day the measure whereof is fifty thousand years.