Cross reference
Genesis 6:15
15 And this is the fashion which thou shalt make it of: The length of the ark shall be three hundred cubits, the breadth of it fifty cubits, and the height of it thirty cubits.
Genesis 7:20
20 Fifteen cubits upward did the waters prevail; and the mountains were covered.
Deuteronomy 3:11
11 For only Og king of Bashan remained of the remnant of giants; behold his bedstead was a bedstead of iron; is it not in Rabbath of the children of Ammon? nine cubits was the length thereof, and four cubits the breadth of it, after the cubit of a man.