'Twenty' in the Bible

The sons of Israel cried to the Lord; for he had nine hundred iron chariots, and he oppressed the sons of Israel severely for twenty years.

He struck them with a very great slaughter from Aroer to the entrance of Minnith, twenty cities, and as far as Abel-keramim. So the sons of Ammon were subdued before the sons of Israel.

So he judged Israel twenty years in the days of the Philistines.

Then his brothers and all his father’s household came down, took him, brought him up and buried him between Zorah and Eshtaol in the tomb of Manoah his father. Thus he had judged Israel twenty years.