Answer:
P + S / P [(r - 1) P - S] dP
Explanation:
If r = 0.10 and S = 900 then,
P + 900 / P [(0.10 - 1) P - 900] dP
Solving the equation we get,
P + 900 = (B - 0.9A)P - 900A
If A = -1,
B = 0.10
t = 0 and P = 10,000
ln 10000 - 1 /9 ln (0.9 * 10000 + 900) + C
C = 10.2326.