In order to calculate the amount Bob has to pay the lottery winners currently, Bob has to calculate the present value of the 225,000 that is to be paid after 10 years
Future value (FV)= 225,000
Number of years (n) = 10
Interest rate (r) = 12% = 0.12
Present value (PV) = FV/(1+r)^n
Present value (PV) = 225,000/(1+0.12)^10
Present value (PV) = 225,000/1.12^10
Present value (PV) = $72,443.98
Amount should bob offer lottery winners currently = $72,443.98