Answer:
roughly 15 years
Explanation:
The formula for continuous compounding is
A = Pe^(rt), where P is the initial amount (principal), r is the interest rate as a decimal fraction, and t is the number of years. Here:
$6900 = $3600*e^(0.043*t). Let's solve this for t. To accomplish that,
take the natural log of both sides:
ln 6900 = ln 3600 + 0.043t. Subtracting ln 3600 from both sides, we get:
8.839 = 8.189 + 0.043t, or 0.6506 = 0.043t. Dividing both sides by 0.043 yields
0.6506
t = --------------- = 15.13 years, or about 15 years 2 months, or roughly 15 years
0.043