Ikrimah narrates from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that the very old man has been granted a concession to break his fast and feed a poor person one mudd for each day, and he does not have to make it up.
(Sayyiduna Ibn Abbas (may Allah be pleased with them both) said: The very old man has been granted a concession to break his fast and feed a poor person in place of each day, and he does not have to make it up.)
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8318