Answer:
Computation of contribution to retirement fund
Annual payment that the investor wants to receive after retirement = 13000
Number of years after retirement = 15
Interest rate = 0.11
Value of the fund at 12th year (Use Present Value Formula) = -93,481.30
Years remaining to retirement = 10
Interest rate = 0.09
Annual contribution upto retirement (Use PMT Formula) = -14,566.27