Determining the correct total issue size when shares are divided among two groups and the counts are disparate (Mutabaayinayn) without commensurability or proportional relationship?
Chapter on the Roots of Inheritance Shares that Increase (Awl)
Al-Mughni
Book of Inheritance Shares (Farā'id)
Primary text
When the counts of the two groups are mutually disparate, neither matching nor proportional, one must multiply the count of one group by the entire allocation of the other group, and then multiply that result by the original base of the shares. If the grandmothers are four and the brothers are three, multiplying 4 by 3 yields 12, and then multiplying 12 by the original base yields the corrected total issue size (e.g., 72). If only one of the counts aligns with its corresponding shares, the fraction (Wifq) of the aligning count is taken, and this is multiplied by the count that did not align, and this result is then used in the standard multiplication process.
Supporting text
If both groups align with their respective shares, they must both be reduced to their corresponding fractions (Wifq), and the calculation proceeds based on these reduced numbers.