Questions: Use the continuous compound interest formula to find the indicated value.
A = 84,000; P = 68,294; r = 6.9%; t = ?
t = years
(Do not round until the final answer. Then round to two decimal places as needed.)
Transcript text: Use the continuous compound interest formula to find the indicated value.
\[
A=\$ 84,000 ; P=\$ 68,294 ; r=6.9 \% ; t=?
\]
$\mathrm{t}=$ $\square$ years
(Do not round until the final answer. Then round to two decimal places as needed.)
Solution
Solution Steps
Step 1: Divide both sides of the equation by P to isolate e^{rt} on one side.
We get \(\frac{A}{P} = e^{rt}\) which simplifies to \(\frac{84000}{68294} = e^{rt}\).
In this case, \(\frac{84000}{68294} = 1.23\).
Step 2: Take the natural logarithm (\(\ln\)) of both sides to solve for \(rt\).
We get \(\ln\left(\frac{84000}{68294}\right) = rt\) which simplifies to \(\ln(1.23) = rt\).
In this case, \(\ln(1.23) = 0.21\).
Step 3: Divide both sides by \(r\) to solve for \(t\).
We get \(t = \frac{\ln\left(\frac{84000}{68294}\right)}{r}\) which simplifies to \(t = \frac{\ln(1.23)}{0.069}\).
In this case, \(t = 3\) years.
Final Answer:
The time it takes for an initial investment of \(68294\) to grow to \(84000\) at a continuous interest rate of \(0.069\) is \(3\) years.