All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
Since the deceased had a half-sister from the mother's side, you should have included her among the list of female heirs. Since you did not do so, we fear that you may have forgotten to include other heirs in the list of heirs.
In any case, what we can say now is that if the deceased did not leave any other heirs besides those mentioned in the question, then her mother gets one-sixth of the estate as her legal share due to the existence of brothers and sisters; Allaah says (what means): {And if he had brothers [and/or sisters], for his mother is a sixth, after any bequest he [may have] made or debt.} [Quran 4:11]
Her half-brother and half-sister from the mother's side get one-third which should be divided among them equally, as Allaah says in regard to more than one son or more than one daughter from the mother's side (what means): {But if they are more than two, they share a third, after any bequest which was made or debt.} [Quran 4:12]
The remainder should be divided among her two full-brothers and her full-sister by Ta‘seeb (by virtue of having a paternal relation with the deceased and not having an allotted share, so they get what is left after the allotted shares have been distributed); the male is entitled to double the share of the female as Allaah says (what means): {If there are both brothers and sisters, the male will have the share of two females. Allaah makes clear to you [His law], lest you go astray. And Allaah is Knowing of all things.} [Quran 4:176]
The half-brother and half-sister from the father's side are not entitled to any part of the inheritance because they are excluded by the existence of full-brothers.
Therefore, the inheritance should be divided into 30 shares. The mother of the deceased gets one-sixth, which is 5 shares; the brother and sister from the mother's side get one-third, which is 10 shares, with each getting 5 shares. Each full-brother gets 6 shares, and the full-sister gets 3 shares.
Allaah Knows best.