Hi Rafa,
Yes, we will pass the referral amount of E to D, and D to C, and C to B, and B to A in the following manner-
Person A receives a 25% commission directly from the revenue, which amounts to $$5,000\ $$ for a total revenue of $20,000.
Person B, referred by A. A also receives 25% of B's commission, which equals 5000/4 = $$1,250\ $$.
Person C, referred by B. C's commission, is $$5,000\ $$, and B receives 25% of C's commission, which is another 5000/4. A, in turn, receives 25% of B's commission due to C, which is 5000/4*4
Person D, referred by C. D's commission, is $$5,000\ $$, and C receives 25% of D's commission, which is another 5000/4. B, in turn, receives 25% of C's commission due to D, which is 5000/4*4. A, in turn, receives 25% of B's commission due to C, which is 5000/4*4*4
This pattern continues, with each new person (E, F, and so on) contributing to the commissions of those who referred them.
To calculate A's total earnings, we can see that it follows a geometric progression (G.P.):
Total earnings for A = Sum to infinite G.P. with the initial term (a) of $$5,000\ $$ and a common ratio (r) of $$\frac{1}{4}\ $$.
Total earnings = $$\frac{a}{1-r} = \frac{5,000}{1-\frac{1}{4}} = \frac{20,000}{3} = Rs. 6,666.67\ $$.
I hope this helps!