'Thirty' in the Bible

So [the] Philistines fought and Israel was defeated and each man fled to his tent, for the slaughter was very great. Thirty thousand foot soldiers from Israel fell.

So Samuel took Saul and his servant and brought them to a room in the building and gave them a place at the head of {the invited guests}. There were about thirty men.

He mustered them at Bezek; the {Israelites} [were] three hundred thousand, and the men of Judah [were] thirty thousand.

Saul [was thirty] {years old} at the beginning of his reign, and he reigned [forty-]two years over Israel.

And the Philistines assembled to fight with Israel, thirty thousand chariots and six thousand horsemen and an army as numerous as sand which [is] on the seashore. And they came up and encamped at Micmash, east of Beth Aven.