How is the inheritance divided between the sons (one male), the mother (one female), and the daughter (one female)?

The mother receives one-sixth as a prescribed share due to the presence of a lineal descendant, based on the Almighty's saying: "And for his parents, each of them is to have a sixth of what he leaves if he has a child." The remainder goes to the son and daughter by way of ta'sib (residuary heirship), with the male receiving the equivalent of the share of two females, based on the Almighty's saying: "Allah instructs you concerning your children: for the male, what is equal to the share of two females." Thus, the inheritance is divided into eighteen shares: the mother receives three shares, the son ten shares, and the daughter five shares. It is obligatory to refer inheritance matters to the Sharia courts for investigation before division.