Sri Sathya Sai Baba gives one more simpler example to explain Prarabhda, Sanchita and Agami karmas.

He explains:
Prarabhda can be compared to the dust that follows in the wake of a bus. When the bus is going, the dust also will be following it. So when the Karma which can be compared to the bus, is running, the Prarabhda, which can be compared to the dust will be pursuing it. When the bus stops and does not travel, then the dust comes and falls over it. But when the bus does not stop and keeps on running, the dust will be only at a distance. So when we are satisfactorily doing our daily duties without interruption, the dust or the Prarabhda will be at a distance and behind us without affecting us.

You may ask how long can we travel in a bus? We have to stop somewhere, It is not so. This road is of three kinds; work, worship and wisdom. This work is related to Karma and dust will be only there. You may take this as a village road. But if you pass some distance, then you will have a better road, a tar road. When the tar road comes, the dust will never fall on the bus. If you go still further you shall reach trunk road, the high way. So the road of karma is called the village road. Bhakti or worship is the town road or the tar road. Wisdom is the highway wherein there is no possibility of the dust coming. When we are following only the path of Karma, this Prarabhda will never come to an end. But, if we do the Karma in a way that we perform all actions for the pleasure and for the satisfaction of God, in worship and dedication to Him, no Prarabhda will trouble us.