The population of Oak Forest is increasing at a rate of 4% per year.
Increase rate, r = 4%
Current population, P = 39,410
time, t = 3 years
Population after 3 years will be:
[tex]P{(1 + \frac{r}{100} )}^{t} \\ \\ = 39410 \times { ( 1 + \frac{4}{100} )}^{3} \\ \\ = 39410 \times {1.04}^{3} \\ \\ = 44330.89 \\ \\ \approx \boxed{44331}[/tex]
Population after 3 years will be 44331