Решить пропорцию: 2/x=19,8/99.

\[\frac{2}{x} = \frac{19,8}{99}\]

\[\frac{2}{x} = \frac{2,2}{11}\]

\[2,2x = 11 \cdot 2\]

\[x = \frac{22}{2,2}\]

\[x = \frac{220}{22}\]

\[x = 10.\]

\[Ответ:x = 10.\]