7. Выполните действия: 1) \(\frac{17}{50}\cdot\frac{15}{34}\); 2) \(2\frac{4}{21}:3\frac{2}{7}\); 3) \(\frac{5}{13}\cdot26\); 4) \(9\frac34:11\frac7{10}\).

1. \(\frac{17}{50}\cdot\frac{15}{34}=\frac{1}{2}\cdot\frac{3}{10}=\frac{3}{20}\).
2. \(2\frac4{21}=\frac{46}{21},\quad 3\frac27=\frac{23}{7}\).
   \(\frac{46}{21}:\frac{23}{7}=\frac{46\cdot7}{21\cdot23}=\frac23\).
3. \(\frac5{13}\cdot26=5\cdot2=10\).
4. \(9\frac34=\frac{39}{4},\quad 11\frac7{10}=\frac{117}{10}\).
   \(\frac{39}{4}:\frac{117}{10}=\frac{39\cdot10}{4\cdot117}=\frac56\).

Ответ: 1) \(\frac3{20}\); 2) \(\frac23\); 3) \(10\); 4) \(\frac56\).