1. **State the problem:**
Mr. and Mrs. Roberts want to invest an amount $P$ now at an interest rate of 8.5% per year compounded continuously, so that in 14 years the investment grows to $8000$.
2. **Formula used:**
The formula for continuous compounding is:
$$A = P e^{rt}$$
where:
- $A$ is the amount after time $t$
- $P$ is the initial principal (amount invested)
- $r$ is the annual interest rate (as a decimal)
- $t$ is the time in years
3. **Identify known values:**
- $A = 8000$
- $r = 0.085$
- $t = 14$
4. **Solve for $P$:**
Rearrange the formula to isolate $P$:
$$P = \frac{A}{e^{rt}}$$
5. **Substitute values:**
$$P = \frac{8000}{e^{0.085 \times 14}}$$
6. **Calculate the exponent:**
$$0.085 \times 14 = 1.19$$
7. **Evaluate $e^{1.19}$:**
$$e^{1.19} \approx 3.287$$
8. **Calculate $P$:**
$$P = \frac{8000}{3.287}$$
9. **Simplify with cancellation shown:**
$$P = \frac{\cancel{8000}}{\cancel{3.287}} \approx 2433.68$$
10. **Final answer:**
Mr. and Mrs. Roberts should invest approximately **2433.68** now to have 8000 in 14 years with continuous compounding at 8.5% interest.
Continuous Compound Ffc2Ba
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