Compound Interest 0532Cb
1. **State the problem:** Calculate the interest earned on an investment of 250000 compounded semi-annually at an interest rate of 7.05% for 6 years.
2. **Formula used:** The compound interest formula is $$A = P \left(1 + \frac{r}{n}\right)^{nt}$$ where:
- $A$ is the amount after interest
- $P$ is the principal (initial investment)
- $r$ is the annual interest rate (decimal)
- $n$ is the number of compounding periods per year
- $t$ is the time in years
3. **Identify values:**
- $P = 250000$
- $r = 7.05\% = 0.0705$
- $n = 2$ (semi-annually)
- $t = 6$
4. **Calculate the amount $A$:**
$$A = 250000 \left(1 + \frac{0.0705}{2}\right)^{2 \times 6} = 250000 \left(1 + 0.03525\right)^{12} = 250000 \times (1.03525)^{12}$$
5. **Calculate $(1.03525)^{12}$:**
$$ (1.03525)^{12} \approx 1.514546 $$
6. **Calculate $A$:**
$$ A = 250000 \times 1.514546 = 378636.5 $$
7. **Calculate interest earned:**
$$ \text{Interest} = A - P = 378636.5 - 250000 = 128636.5 $$
8. **Compare with options:** The closest option to 128636.5 is **128638.60**.
**Final answer:** The interest earned is **128638.60**.