Genesis 47:24
And it shall come to pass in the increase, that ye shall give the fifth part unto Pharaoh, and four parts shall be your own, for seed of the field, and for your food, and for them of your households, and for food for your little ones. And it shall come to pass in the increase, that ye shall give the fifth part unto Pharaoh, and four parts shall be your own, for seed of the field, and for your food, and for them of your households, and for food for your little ones.
The arrangement belongs to the time after the Egyptians surrendered their land to Pharaoh during the famine. Under it they were to give him one fifth of the harvest from the increase and keep the remaining four parts for themselves, for seed of the field, for food, and for their households and little ones. Joseph's father and brothers stood apart from the Egyptians in this, in that they were not enslaved and were not required to pay this fifth-part tax. Instead they received land and food in recognition of Joseph's service. Joseph was allowed to provide them generously with food.