إن شاء أخذ الجميع كل ذراع بدرهم وإن شاء فسخ البيع
Translation: The buyer may take all of it at one dirham for every cubit, or rescind the sale.
The contract stated 100 cubits at one dirham each; 110 are found. The buyer may:
1. Take the entire 110 cubits for 110 dirhams, or
2. Rescind the sale.
Taking all 110 for only 100 is not the option stated for this contract. The extra length brings an added payment obligation, so the buyer retains a choice.
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Kitab al-Buyu: Shortage, Surplus, Buyer Options and Price Allocation
إن شاء أخذ الجميع كل ذراع بدرهم وإن شاء فسخ البيع
Translation: The buyer may take all of it at one dirham for every cubit, or rescind the sale.
The contract stated 100 cubits at one dirham each; 110 are found. The buyer may:
1. Take the entire 110 cubits for 110 dirhams, or
2. Rescind the sale.
Taking all 110 for only 100 is not the option stated for this contract. The extra length brings an added payment obligation, so the buyer retains a choice.