'Twelve' in the Bible

Then I set apart twelve leading priests, Sherebiah, Hashabiah, and ten of their brothers (relatives),

Also the [former] exiles who had come from the captivity offered burnt offerings to the God of Israel: 12 bulls for all Israel, 96 rams, 77 lambs, and 12 male goats for a sin offering. All this was a burnt offering to the Lord.