Determining the correct total issue size when shares are divided among two groups (Fariqayn) and the counts of claimants are equal (Mutamathilayn)?

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If the claimants are divided into two groups and their respective counts are identical, the correct procedure is to multiply one of the counts by the original base of the shares (Asl al-Masa'alah). For example, in a case involving a spouse, three grandmothers, and three brothers, where the original base is six (three to the spouse, one to the grandmothers, and two to the brothers), multiplying one count by the base (e.g., 3 x 6) results in 18, which becomes the new total issue size. The subsequent division process mirrors that used when the division occurs among only one group. If the claimants in one group equal their allotted shares proportionally (e.g., six brothers matching half their share), they are reduced to the actual number of shares (three).