What is the division of inheritance between the grandfather and a sister?

Supporting text

Seven opinions concerning this distribution exist. The opinion of Abu Bakr As-Siddiq and his supporters grants the mother one-third, and the remainder goes to the grandfather. Zayd ibn Thabit and his followers assign the mother one-third, making the total based on three shares, leaving two shares to be divided between the sister and the grandfather on a basis of three, resulting in a division valid from nine shares. Ali's opinion assigns the sister one-half, the mother one-third, and the grandfather one-sixth. Umar and Abdullah ibn Mas'ud held that the sister receives one-half, the mother receives one-third of what remains, and the final remainder goes to the grandfather. Ibn Mas'ud also opined that the mother receives one-sixth, and the grandfather receives the remainder, which is identical in meaning to the first opinion mentioned. Ibn Mas'ud also stated that the sister receives one-half, and the remainder is divided equally (halves) between the grandfather and the mother, making the total four shares, known as one of Ibn Mas'ud's square divisions. Uthman's opinion assigned the shares among them in thirds, where each heir receives one-third. This is known as Uthman's triangular division, and the issue is also called Al-Musabba'a (the division of seven) because the different opinions return to six fundamental meanings.