Genesis 18:28

Peradventure there should lack five of the fifty righteous,
&c.] Or there should be but forty five; for Abraham perceived, by the Lord's answer, that there were not fifty righteous persons in the place: wilt thou destroy all the city for [lack of] five?
Abraham proceeds gradually in his requests, and does not ask too much at once, lest he should not succeed: and he said, if l find there forty and five, I will not destroy [it];
that is, forty five righteous persons.