he bought with, because he has taken from him a ninth of his sold property. If he takes it by both contracts, he takes from the second all that is in his possession, and he takes from the first half of a ninth, which is two shares out of thirty-six. Thus, he comes to possess twenty shares, which is five ninths. Sixteen shares remain in the possession of the first, which is four ninths. He pays him a third of the first price, and he pays the second eight ninths of the second price, and the second has recourse against the first for a ninth of the second price.

Section: If there is a house between three people, Zayd having half of it, Amr having a third of it, and Bakr having a sixth of it, and Bakr buys a third of the house from Zayd, then sells a sixth of it to Amr, and Amr does not know [about his purchase of the third], then learns of it, he has the right to demand his right to the preemption of the third, which is two thirds of it, and that is two ninths of the house. He takes two thirds of that from Bakr, and the remaining third has come into his possession by his purchase of the sixth. So he annuls his sale of it and takes it by the preemption of the first sale. Five ninths of his sold property remain, and Zayd has a third of his preemption, so it is divided between them in thirds. The problem is correctly resolved from one hundred and sixty-two shares. The sold third is fifty-four shares. Amr has two thirds of it by his preemption, which is thirty-six shares; he takes two thirds of it from Bakr, which is twenty-four shares, and a third of it is in his possession, which is twelve shares. The sixth which he bought is twenty-seven shares; he has already taken twelve of it by preemption, leaving fifteen of it, of which he has two thirds, which is ten, and Zayd takes five of it. Thus, Zayd has thirty-two shares, Bakr has thirty shares, and Amr has one hundred shares, which is half of the house, a ninth of it, and half a ninth of a ninth. Amr pays Bakr two thirds of the price of the sale.