'Eighteen' in the Bible

Jehoiachin was eighteen years old when he began to reign; and he reigned in Jerusalem three months: and his mother's name was Nehushta the daughter of Elnathan of Jerusalem.

The height of the one pillar was eighteen cubits, and a capital of brass was upon it; and the height of the capital was three cubits, with network and pomegranates upon the capital round about, all of brass: and like unto these had the second pillar with network.