6 And, if it be from a month old, even unto five years old, then shall thine estimate be––for the male, five shekels of silver,––and, for the female, thine estimate [shall be] three shekels of silver.
Leviticus 27:6 Cross References - Rotherham
Numbers 3:40-43
40 And Yahweh said unto Moses: Number thou every firstborn male belonging to the sons of Israel, from one month old and upwards,––and reckon up the number of their names;
41 then shalt thou take the Levites for me, me Yahweh, instead of every firstborn among the sons of Israel,––also the cattle of the Levites, instead of every firstling among the cattle of the sons of Israel.
42 So then Moses numbered, as Yahweh commanded him,––every firstborn among the sons of Israel.
43 And it was so––that all the firstborn of the males, in the counting of names from one month old and upwards, of such as were numbered of them,––were two–and–twenty thousand, two hundred and seventy–three.
Numbers 18:14-16
14 every devoted thing in Israel, thine, shall it be:
15 every thing that is born first––of all flesh that may be offered unto Yahweh, among men and among beasts, shall be thine,––only thou shalt, redeem, the firstborn of men, and, the firstborn of unclean beasts, shalt thou redeem.
16 And, as to the redemption price thereof, from a month old, shalt thou redeem, by thine estimate, five shekels of silver, by the shekel of the sanctuary,––twenty gerahs, it is.