1. **State the problem:** We want to find the annual internal rate of return (IRR) compounded monthly for an investment that costs 12500 today and returns 25550 in 6 years.
2. **Formula used:** The future value formula for compound interest is
$$A = P \left(1 + \frac{r}{n}\right)^{nt}$$
where:
- $A$ is the amount after time $t$
- $P$ is the principal (initial investment)
- $r$ is the annual interest rate (decimal)
- $n$ is the number of compounding periods per year
- $t$ is the number of years
3. **Given values:**
- $P = 12500$
- $A = 25550$
- $n = 12$ (monthly compounding)
- $t = 6$
4. **Substitute values into the formula:**
$$25550 = 12500 \left(1 + \frac{r}{12}\right)^{12 \times 6} = 12500 \left(1 + \frac{r}{12}\right)^{72}$$
5. **Divide both sides by 12500:**
$$\frac{25550}{12500} = \left(1 + \frac{r}{12}\right)^{72}$$
$$2.044 = \left(1 + \frac{r}{12}\right)^{72}$$
6. **Take the 72nd root of both sides:**
$$\sqrt[72]{2.044} = 1 + \frac{r}{12}$$
7. **Calculate the 72nd root:**
$$1 + \frac{r}{12} = 2.044^{\frac{1}{72}}$$
Using a calculator:
$$2.044^{\frac{1}{72}} \approx 1.0102$$
8. **Solve for $r$:**
$$1 + \frac{r}{12} = 1.0102$$
$$\frac{r}{12} = 1.0102 - 1 = 0.0102$$
$$r = 0.0102 \times 12 = 0.1224$$
9. **Convert to percentage:**
$$r = 0.1224 = 12.24\%$$
**Final answer:** The annual internal rate of return compounded monthly is **12.24%**.
Annual Irr 042C70
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