The wavelength of the first line of Balmer series is $6563 \stackrel{\mathrm{o}}{\mathrm{A}}$. The Rydberg's constant is

$\begin{array}{l}\frac{1}{\mathrm{\lambda }}=\mathrm{R}\left[\frac{1}{2^2}-\frac{1}{3^2}\right]\\ \mathrm{or} \frac{1}{\mathrm{\lambda }}=\mathrm{R}\left[\frac{1}{4}-\frac{1}{9}\right] \mathrm{or} \frac{1}{\mathrm{\lambda }}=\mathrm{R}\frac{5}{36}\\ \mathrm{or} \mathrm{R}=\frac{36}{5\mathrm{\lambda }}=\frac{36}{5\times 6563\times {10}^{-10}}{\mathrm{m}}^{-1}\\ =\frac{36000}{5\times 6563}\times {10}^7{\mathrm{m}}^{-1}\\ =1.097\times {10}^7{\mathrm{m}}^{-1}\end{array}$