1. **State the problem:**
Declan invested some prize money in a savings account with compound interest at 8% per annum. After 14 years, the amount in the account is 14685.97. We need to find the initial investment amount.
2. **Formula used:**
The compound interest formula is:
$$A = P \times (1 + r)^t$$
where:
- $A$ is the amount after time $t$
- $P$ is the principal (initial investment)
- $r$ is the annual interest rate (as a decimal)
- $t$ is the time in years
3. **Given values:**
- $A = 14685.97$
- $r = 0.08$
- $t = 14$
4. **Rearrange the formula to find $P$:**
$$P = \frac{A}{(1 + r)^t}$$
5. **Calculate $(1 + r)^t$:**
$$1 + r = 1 + 0.08 = 1.08$$
$$1.08^{14} = 2.937686$$ (rounded to 6 decimal places)
6. **Calculate $P$:**
$$P = \frac{14685.97}{2.937686}$$
7. **Show cancellation step:**
$$P = \frac{\cancel{14685.97}}{\cancel{2.937686}}$$ (just indicating division)
8. **Perform division:**
$$P \approx 5000.00$$
9. **Final answer:**
Declan initially invested approximately **5000** (to the nearest 1).
Compound Interest 42Ffbe
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