\[\boxed{\text{5.268.}}\]
\[1)\ (654x - 10\ 590)\ :57 = 778\]
\[654x - 10\ 590 = 778 \cdot 57\]
\[654x - 10\ 590 = 44\ 346\]
\[654x = 44\ 346 + 10\ 590\]
\[654x = 54\ 936\]
\[x = 54\ 936\ :654\]
\[x = 84.\ \]
\[Ответ:\ 84.\ \]
\[2)\ (54x + 22) \cdot 315 = 23\ 940\]
\[54x + 22 = 23\ 940\ :315\]
\[54x + 22 = 76\]
\[54x = 76 - 22\]
\[54x = 54\]
\[x = 54\ :54\]
\[x = 1\text{.\ }\]
\[Ответ:1.\]