عَنِ ابْنِ عَبَّاسٍ رَضِيَ اللَّهُ عَنْهُمَا قَالَ كُنَّا مَعَ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ فِي سَفَرٍ فَحَضَرَ النَّحْرُ فَذَبَحْنَا الْبَقَرَةَ عَنْ سَبْعَةٍ وَالْبَعِيرَ عَنْ عَشَرَةٍ
It is narrated from Sayyiduna Abdullah bin Abbas, may Allah be pleased with them both, he says: We were on a journey with the Noble Prophet, peace and blessings be upon him, when the occasion of Eid al-Adha arrived, so we slaughtered a cow on behalf of seven people and a camel on behalf of ten people.