\(\left\)\(30\frac{4}{5} + 27\frac{1}{5} \right\) \(\cdot\) \(\frac{9}{10}\) : \(\left\)\(31\frac{16}{25} - 12\frac{6}{25} \right\)

Решение:

Выполним действия по порядку:

1. 
   \[ 30\frac{4}{5} + 27\frac{1}{5} = 30 + \frac{4}{5} + 27 + \frac{1}{5} = 57 + \frac{5}{5} = 57 + 1 = 58 \]
   
2. 
   \[ 31\frac{16}{25} - 12\frac{6}{25} = 31 + \frac{16}{25} - 12 - \frac{6}{25} = 19 + \frac{10}{25} = 19 + \frac{2}{5} = 19.4 \]
   
3. 
   \[ 58 \cdot \frac{9}{10} = \frac{58 ' 9}{10} = \frac{522}{10} = 52.2 \]
   
4. 
   \[ 52.2 : 19.4 = \frac{522}{10} : \frac{194}{10} = \frac{522}{194} = \frac{261}{97} \]
   

Ответ: \(\frac{261}{97}\)