Numbers 3:47-49

Amplified Bible

⁴⁷ you shall take five shekels apiece, per head, you shall take them in terms of the sanctuary shekel (the shekel is twenty gerahs), ⁴⁸ and give the money, the ransom (redemption price) of those who outnumber the Levites to Aaron and to his sons.” ⁴⁹ So Moses took the ransom (redemption) money from those who were in excess, beyond those ransomed by the Levites;