TSK · Exodus 30:14

You and Aaron are to number all in Israel who can serve in the army, those who are twenty years old or older, by their divisions.

And they were as follows:The descendants of Reuben, the firstborn son of Israel: According to the records of their clans and families, all the males twenty years old or older who could serve in the army were listed by name individually.

“Take a census of the whole community of Israelites, from twenty years old and upward, by their clans, everyone who can serve in the army of Israel.”

The shekel will be twenty gerahs. Sixty shekels will be a mina for you.