Exodus 7:7
7:7 Now Moses was eighty years old and Aaron was eighty-three years old when they spoke to Pharaoh.
Exodus 32:28
32:28 The Levites did what Moses ordered, and that day about three thousand men of the people died.
Exodus 34:23
34:23 At three times in the year all your men must appear before the Lord God, the God of Israel.