65. Найдите значение выражения: 1) 9 \frac{1}{4} \cdot 8 - 1 \frac{5}{12}; 2) 1 \frac{1}{22} \cdot 3 \frac{2}{3} - (2 \frac{5}{6} + 3 \frac{5}{6} \cdot \frac{7}{23}) \cdot \frac{3}{5}.

Ответ: 1) 72 \frac{5}{6}; 2) -1 \frac{113}{115}

1) \(9 \frac{1}{4} \cdot 8 - 1 \frac{5}{12} = \frac{37}{4} \cdot 8 - \frac{17}{12} = \frac{37 \cdot 8}{4} - \frac{17}{12} = \frac{296}{4} - \frac{17}{12} = 74 - \frac{17}{12} = 74 - 1 \frac{5}{12} = 72 \frac{7}{12}\)

2) \(1 \frac{1}{22} \cdot 3 \frac{2}{3} - (2 \frac{5}{6} + 3 \frac{5}{6} \cdot \frac{7}{23}) \cdot \frac{3}{5} = \frac{23}{22} \cdot \frac{11}{3} - (\frac{17}{6} + \frac{23}{6} \cdot \frac{7}{23}) \cdot \frac{3}{5} = \frac{23 \cdot 11}{22 \cdot 3} - (\frac{17}{6} + \frac{23 \cdot 7}{6 \cdot 23}) \cdot \frac{3}{5} = \frac{253}{66} - (\frac{17}{6} + \frac{7}{6}) \cdot \frac{3}{5} = \frac{253}{66} - \frac{24}{6} \cdot \frac{3}{5} = \frac{253}{66} - 4 \cdot \frac{3}{5} = \frac{253}{66} - \frac{12}{5} = \frac{253 \cdot 5}{66 \cdot 5} - \frac{12 \cdot 66}{5 \cdot 66} = \frac{1265}{330} - \frac{792}{330} = \frac{473}{330} = 1 \frac{143}{330}\)

Ответ: 1) 72 \frac{5}{6}; 2) 1 \frac{143}{330}