First, let's convert the distance of 4 lightyears to miles:
[tex]4\text{ ly}=4\cdot5.879\cdot10^{12}\text{ miles}=23.516\cdot10^{12}\text{ miles}[/tex]Now, let's find the time required:
[tex]\begin{gathered} distance=speed\cdot time\\ \\ 23.516\cdot10^{12}=38500\cdot t\\ \\ t=\frac{23.516\cdot10^{12}}{38500}\\ \\ t=6.10805\cdot10^8\text{ hours} \end{gathered}[/tex]Then, we need to convert from hours to years:
[tex]6.10805\cdot10^8\text{ hours}=\frac{6.10805\cdot10^8}{8760}=6.97266\cdot10^4\text{ years}[/tex]Therefore it will take approximately 69727 years.