As per the textbook context, in the absence of any information regarding profit sharing ratio in which the remaining partners acquire the share of retiring partner, it is assumed that they will acquire it in the old profit sharing ratio. Therefore, the continuing partners share future profits in their old ratio. The old ratio among Rahul : Robin : Rajesh is 3 : 2 : 1. When one partner retires, the remaining partners continue in their respective proportions from the original ratio.