Respuesta :
a) To calculate Godfrey's retirement savings needs, we use the future value formula for an annuity with monthly compounding:
Future Value (FV) = Payment (P) × ((1 + r)^(nt) - 1) / r + Payment (P) × (1 + r)^(nt) × t
Where:
- FV is the future value (target amount) needed for retirement.
- P is the monthly withdrawal amount ($40,000).
- r is the monthly interest rate (12% / 12 = 1% or 0.01).
- n is the number of times the interest is compounded per period (monthly).
- t is the total number of periods (15 years * 12 months = 180 months).
By plugging in the values:
FV = 40,000 × ((1 + 0.01)^180 - 1) / 0.01 + 40,000 × (1 + 0.01)^180 × 15
FV ≈ 40,000 × (385.3212731) + 40,000 × (8.938248032)
FV ≈ 15,412,851.25 + 357,529.9213
FV ≈ 15,770,381.17
So, the target amount for Godfrey's retirement savings is approximately $15,770,381.17.
b) For Plan (1), Godfrey would need to make a single deposit of $4,086,356.21.
c) For Plan (2), we need to find the single payment required at his 55th birthday.
First, we find the present value (PV) of the annuity payments:
PV_annuity ≈ 72 × ((1 - (1 + 0.01)^-72) / 0.01)
PV_annuity ≈ 72 × (47.525154)
PV_annuity ≈ 3,421,114.35
Then, we find the remaining balance to reach the target amount:
Remaining Balance = 15,770,381.17 - 3,421,114.35
Remaining Balance ≈ 12,349,266.82
Finally, we calculate the single payment:
Single Payment ≈ 12,349,266.82 / (1 + 0.01)^72
Single Payment ≈ 12,349,266.82 / 5.653297705
Single Payment ≈ 2,183,026.89
So, for Plan (2), the single payment required at his 55th birthday is approximately $2,183,026.89.
Future Value (FV) = Payment (P) × ((1 + r)^(nt) - 1) / r + Payment (P) × (1 + r)^(nt) × t
Where:
- FV is the future value (target amount) needed for retirement.
- P is the monthly withdrawal amount ($40,000).
- r is the monthly interest rate (12% / 12 = 1% or 0.01).
- n is the number of times the interest is compounded per period (monthly).
- t is the total number of periods (15 years * 12 months = 180 months).
By plugging in the values:
FV = 40,000 × ((1 + 0.01)^180 - 1) / 0.01 + 40,000 × (1 + 0.01)^180 × 15
FV ≈ 40,000 × (385.3212731) + 40,000 × (8.938248032)
FV ≈ 15,412,851.25 + 357,529.9213
FV ≈ 15,770,381.17
So, the target amount for Godfrey's retirement savings is approximately $15,770,381.17.
b) For Plan (1), Godfrey would need to make a single deposit of $4,086,356.21.
c) For Plan (2), we need to find the single payment required at his 55th birthday.
First, we find the present value (PV) of the annuity payments:
PV_annuity ≈ 72 × ((1 - (1 + 0.01)^-72) / 0.01)
PV_annuity ≈ 72 × (47.525154)
PV_annuity ≈ 3,421,114.35
Then, we find the remaining balance to reach the target amount:
Remaining Balance = 15,770,381.17 - 3,421,114.35
Remaining Balance ≈ 12,349,266.82
Finally, we calculate the single payment:
Single Payment ≈ 12,349,266.82 / (1 + 0.01)^72
Single Payment ≈ 12,349,266.82 / 5.653297705
Single Payment ≈ 2,183,026.89
So, for Plan (2), the single payment required at his 55th birthday is approximately $2,183,026.89.