Is a sale permissible if the seller informed the buyer of the measure but sold the entire lot (*mujazafah*) for a set price, contingent on the actual amount being more or less than stated?

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This transaction is not permissible. This is based on a report transmitted through Al-Athram on the authority of Al-Hakam, stating that food arrived for Uthman during the time of the Prophet, peace be upon him, and when the Prophet inspected it, Uthman stated the measure in the container and the price paid. The Prophet replied, 'When the measure is named, then measure it out.' Imam Ahmad stated his dislike for a situation where a seller informs the buyer of the measure per container, and the buyer accepts based on that information without further measuring, citing the Prophet's saying to Uthman. When questioned about the concept of breaking open containers resulting in invalidity, Imam Ahmad suggested opening one and weighing the remainder.