Determining the correct total issue size when shares are divided among two groups and the counts have a common fractional relationship (Muttafiqayn)?

Chapter on the Roots of Inheritance Shares that Increase (Awl)

Al-Mughni

Book of Inheritance Shares (Farā'id)

Book 32 · Issue 4 · Bab 2

Open in Qurani

Primary text

When the two counts share a common fractional relationship (such as one being half, a third, or a quarter of the other), one count is reduced to its corresponding fraction. This reduced number is then multiplied by the entirety of the other count. The resulting number is then multiplied by the original base of the shares to establish the final, corrected total issue size. For example, if there are nine brothers and six grandmothers, they share a third relationship. The grandmothers are reduced to their third (two), multiplied by the brothers' count (nine), yielding eighteen. This eighteen is then multiplied by the original base to yield the corrected total issue size (e.g., 108).