Leviticus 6:5

6:5 or anything about which he swears falsely. He must restore it in full and add one fifth to it; he must give it to its owner when he is found guilty.

Leviticus 27:27

27:27 If, however, it is among the unclean animals, he may ransom it according to its conversion value and must add one fifth to it, but if it is not redeemed it must be sold according to its conversion value.

Leviticus 5:16

5:16 And whatever holy thing he violated he must restore and must add one fifth to it and give it to the priest. So the priest will make atonement on his behalf with the guilt offering ram and he will be forgiven.”