How is inheritance calculated for two male heirs (son, full brother, husband) and two female heirs (mother, daughter, full sister)?

If the deceased leaves behind only a mother, a husband, a son, a daughter, a full brother, and a full sister, then:

The mother receives one-sixth due to the presence of a lineal descendant. The husband receives one-fourth due to the presence of a lineal descendant. The remainder goes to the son and the daughter by way of ta'sib (residuary heirship), with the male receiving the share of two females. The full brother and full sister receive nothing as they are completely excluded by the presence of the son.

The inheritance is divided into thirty-six shares: The mother receives six shares. The husband receives nine shares. The son receives fourteen shares. The daughter receives seven shares.

It is obligatory to refer inheritance matters to the Sharia courts for investigation.