ASV(i)
15 Everything that openeth the womb, of all flesh which they offer unto Jehovah, both of man and beast shall be thine: nevertheless the first-born of man shalt thou surely redeem, and the firstling of unclean beasts shalt thou redeem.
16 And those that are to be redeemed of them from a month old shalt thou redeem, according to thine estimation, for the money of five shekels, after the shekel of the sanctuary (the same is twenty gerahs).
17 But the firstling of a cow, or the firstling of a sheep, or the firstling of a goat, thou shalt not redeem; they are holy: thou shalt sprinkle their blood upon the altar, and shalt burn their fat for an offering made by fire, for a sweet savor unto Jehovah.