jmc

We immediately see some canceling. We see powers of ten on the top and on the bottom of the fraction, and we make quick work of this: $$\frac{10^7}{5\times 10^4}=\frac{10^3}{5}$$ We know that $10^3=10\times 10\times 10$, so $$\begin{array}{rl}\frac{10^3}{5}& =\frac{10\times 10\times 10}{5}\\ & =2\times 10\times 10\\ & =200\end{array}$$ So the answer is $\boxed{200}$