Considering that the man intended for his wife to have at the very least
one-third of the estate, the wife can have exactly one-third. That leaves
two-thirds of the estate to be divided between the son and the daughter.
The son should then recieve two-thirds of the remaining estate and the daughter
one-third of the remaining estate.
That means the wife will get three-ninths of the estate. The son will receive
four-ninths of the estate and the daughter will receive two-ninths of the
estate. This makes the most sense because the son still receives more of
the estate than the mother and the mother receives more than the daughter.