If $∆{\mathrm{r}}_1$ represents the difference in radii of stationary orbits for $\mathrm{n}=3$ and $\mathrm{n}=4$ in a hydrogen atom and $∆{\mathrm{r}}_2$ represents the difference in radii of stationary orbits for $\mathrm{n}=8$ and $\mathrm{n}=9$, then the value of $\frac{∆{\mathrm{r}}_1}{∆{\mathrm{r}}_2}$ is