Add one to the number of sons and multiply it by the denominator of the fraction; it becomes sixteen. You pay five to the legatee and subtract four from it; one share remains for him, and five for each son. If you wish, you may allocate one-fourth to each son and divide the remaining fourth between him and them by four. If he says: "except one-fourth of what remains after the share," then add a share and a fourth to the shares of the sons and multiply it by four; it becomes seventeen. The legatee has two shares, and each son has five. By algebra, you take an estate and pay from it a share to the legatee, and subtract from it one-fourth of the remainder—which is one-fourth of an estate minus one-fourth of a share—and you are left with an estate and a fourth minus a share and a fourth, which equals the shares of the sons, which are three. Reconcile and equate; the share comes out to five and the estate to seventeen. If he says: "except one-fourth of what remains after the bequest," you make the denominator three and add its third to it; it becomes four, which is the share. You add a share and a third to the number of sons and multiply it by three; it becomes thirteen, which is the estate. If you wish, you may say: the entire estate is three shares and a bequest, and the bequest is a share minus one-fourth of what remains after it, which is three-fourths of a share; thus, one-fourth of a share remains, which is the bequest. It becomes clear that the entire estate is three and a fourth; expand them, and it becomes thirteen. There are other methods for these problems besides what we have mentioned. And Allah knows best.

Section: If he says: "I have bequeathed to you the equivalent of the share of one of my sons minus one-third of what remains of the third," take the denominator of the fraction, one-third of the third, which is nine, and add a share to it; it becomes ten, which is the share. Add a share and a third to the shares of the sons and multiply that by nine; it becomes thirty-nine. Pay ten to the legatee and subtract from it one-third of the remainder of the third—one share—and nine remain for him, and each son has ten. If he says: "except one-third of what remains of the third after the bequest," you make the estate six and add a share to it; it becomes seven, which is the share. You add a share and a half to the shares of the sons.