Numbers 3:45-47

Amplified Bible

⁴⁵ “Take the Levites [for Me] instead of all the firstborn among the sons of Israel, and the cattle of the Levites instead of their cattle. And the Levites shall be Mine. I am the Lord. ⁴⁶ For the ransom (redemption price) of the 273 of the firstborn of the Israelites who outnumber the Levites, ⁴⁷ you shall take five shekels apiece, per head, you shall take them in terms of the sanctuary shekel (the shekel is twenty gerahs),