Debt Rescheduling
1. **State the problem:** John owes P10,000 due in 4 years and P3,000 due in 5 years. He reschedules to pay three sums: $X$ now, $2X$ in 3 years, and $3X$ in 5 years. The interest rate is 10% per annum compounded monthly. We need to find $X$ such that the present value of the new payments equals the present value of the original debts.
2. **Calculate the present value (PV) of the original debts:**
- Interest rate per month $i = \frac{10\%}{12} = 0.0083333$ (approx)
- Number of months for 4 years $n_1 = 4 \times 12 = 48$
- Number of months for 5 years $n_2 = 5 \times 12 = 60$
PV of P10,000 due in 4 years:
$$PV_1 = \frac{10000}{(1 + 0.0083333)^{48}}$$
PV of P3,000 due in 5 years:
$$PV_2 = \frac{3000}{(1 + 0.0083333)^{60}}$$
Total PV of original debts:
$$PV_{total} = PV_1 + PV_2$$
3. **Calculate the present value of the rescheduled payments:**
- Payment $X$ now has PV = $X$
- Payment $2X$ in 3 years (36 months):
$$PV_{2X} = \frac{2X}{(1 + 0.0083333)^{36}}$$
- Payment $3X$ in 5 years (60 months):
$$PV_{3X} = \frac{3X}{(1 + 0.0083333)^{60}}$$
Total PV of rescheduled payments:
$$PV_{rescheduled} = X + \frac{2X}{(1 + 0.0083333)^{36}} + \frac{3X}{(1 + 0.0083333)^{60}}$$
4. **Set the total present values equal and solve for $X$:**
$$PV_{total} = PV_{rescheduled}$$
$$\Rightarrow PV_1 + PV_2 = X + \frac{2X}{(1 + 0.0083333)^{36}} + \frac{3X}{(1 + 0.0083333)^{60}}$$
5. **Calculate numerical values:**
Calculate $(1 + 0.0083333)^{48} \approx 1.488863$ and $(1 + 0.0083333)^{60} \approx 1.647009$ and $(1 + 0.0083333)^{36} \approx 1.395618$
Then:
$$PV_1 = \frac{10000}{1.488863} \approx 6717.57$$
$$PV_2 = \frac{3000}{1.647009} \approx 1821.99$$
$$PV_{total} = 6717.57 + 1821.99 = 8539.56$$
6. **Calculate the coefficients for $X$:**
$$PV_{rescheduled} = X + \frac{2X}{1.395618} + \frac{3X}{1.647009} = X + 1.4337X + 1.8219X = 4.2556X$$
7. **Solve for $X$:**
$$4.2556X = 8539.56$$
$$X = \frac{8539.56}{4.2556} \approx 2006.88$$
8. **Final payments:**
- Now: $X = 2006.88$
- In 3 years: $2X = 4013.76$
- In 5 years: $3X = 6020.64$
**Answer:** John’s payments are approximately P2006.88 now, P4013.76 in 3 years, and P6020.64 in 5 years.