All the versions agree that from Abraham up until Moses and the exodus of the Jews from Egypt, there are 505 years, which are calculated in the following way.
In the 75th year of Abraham, God appeared to him and said that he would give the promised land to his offspring.
It is written [ Genesis, 12'4-7 ]: “Abraham was seventy-five years old when he set out from Haran.
He took his wife Sarah, and his nephew Lot.” And a little later, Scripture adds: “The Lord appeared to Abraham, and said, 'To your offspring I give this land.' “ So from the first year of Abraham [until this promise made by God], there are 75 years; and from the 75th year of Abraham until the exodus of the Jews from Egypt, there are 430 years.
The Apostle Paul bears witness to this, when he says [ Galatians, 3'17-18 ]: “The law, introduced 430 years later, does not set aside the covenant previously established by God and thus do away with the promise.” And shortly afterwards, he adds: “God in his grace gave it to Abraham through a promise.” Abraham's son Isaac was born in Abraham's 100th year, 25 years after the promise which God made to him.
From then until the exodus from Egypt there are 405 years, so that the total time from the promise until [the exodus] is 430 years.