While battling hydra, Hercules found that for every head that he cut, three heads grew for hydra. After every cut, the number of heads increases. What can be said about this increase?
The increase is like that of simple interest
For every cut of hercules’ sword, one head dies and 3 sprout up. Hence in every sword cut 2 heads are added. Assuming that Hercules cuts one head per a period of time, the number of heads getting added at the end of this period is fixed.