Evaluate the problem and then put solution into scientific notation

Ok, let's simplify:
[tex]\begin{gathered} \frac{7.87\cdot10^{-6}}{4.39\cdot10^{-2}}= \\ \frac{4.39\cdot10^2}{7.87\cdot10^6}= \\ 0.557\cdot10^{2-6^{}}= \\ 0.557\cdot10^{-4}= \\ 5.57\cdot10^{-5} \end{gathered}[/tex]