Numbers 3:46-49

46 And a as the redemption price for the 273 of the firstborn of the people of Israel, over and above the number of the male Levites, 47 you shall take b five shekels
A  shekel was about 2/5 ounce or 11 grams
per head; you shall take them according to d the shekel of the sanctuary (the shekel of twenty gerahs
A  gerah was about 1/50 ounce or 0.6 gram
),
48 and give the money to Aaron and his sons as the redemption price for those who are over.” 49 So Moses took the redemption money from those who were over and above those redeemed by the Levites.
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