Вычислите: 1) 1 19/29·7/48; 2) 1 13/58·9/71; 3) 1 15/34·17/49; 4) 1 11/45·25/56; 5) 7/12:2 1/4; 6) 9/14:1 4/7; 7) 8/11:2 2/5; 8) 6/13:1 1/8; 9) 1/15+4 4/5·2/21; 10) 3/20+3 3/4·1/27; 11) 1/14+2 1/12·2/15; 12) 10/21+2 2/15·3/14.

1. Преобразуем смешанное число: \(1\frac{19}{29}=\frac{48}{29}\). Тогда \(\frac{48}{29}\cdot\frac{7}{48}=\frac{7}{29}\).
2. \(1\frac{13}{58}=\frac{71}{58}\), поэтому \(\frac{71}{58}\cdot\frac{9}{71}=\frac{9}{58}\).
3. \(1\frac{15}{34}=\frac{49}{34}\), поэтому \(\frac{49}{34}\cdot\frac{17}{49}=\frac{17}{34}=\frac{1}{2}\).
4. \(1\frac{11}{45}=\frac{56}{45}\), поэтому \(\frac{56}{45}\cdot\frac{25}{56}=\frac{25}{45}=\frac{5}{9}\).
5. \(\frac{7}{12}:2\frac{1}{4}=\frac{7}{12}:\frac{9}{4}=\frac{7}{12}\cdot\frac{4}{9}=\frac{7}{27}\).
6. \(\frac{9}{14}:1\frac{4}{7}=\frac{9}{14}:\frac{11}{7}=\frac{9}{14}\cdot\frac{7}{11}=\frac{9}{22}\).
7. \(\frac{8}{11}:2\frac{2}{5}=\frac{8}{11}:\frac{12}{5}=\frac{8}{11}\cdot\frac{5}{12}=\frac{10}{33}\).
8. \(\frac{6}{13}:1\frac{1}{8}=\frac{6}{13}:\frac{9}{8}=\frac{6}{13}\cdot\frac{8}{9}=\frac{16}{39}\).
9. Сначала выполняем умножение: \(\frac{1}{15}+4\frac{4}{5}\cdot\frac{2}{21}=\frac{1}{15}+\frac{24}{5}\cdot\frac{2}{21}=\frac{1}{15}+\frac{16}{35}=\frac{11}{21}\).
10. \(\frac{3}{20}+3\frac{3}{4}\cdot\frac{1}{27}=\frac{3}{20}+\frac{15}{4}\cdot\frac{1}{27}=\frac{3}{20}+\frac{5}{36}=\frac{13}{45}\).
11. \(\frac{1}{14}+2\frac{1}{12}\cdot\frac{2}{15}=\frac{1}{14}+\frac{25}{12}\cdot\frac{2}{15}=\frac{1}{14}+\frac{5}{18}=\frac{22}{63}\).
12. \(\frac{10}{21}+2\frac{2}{15}\cdot\frac{3}{14}=\frac{10}{21}+\frac{32}{15}\cdot\frac{3}{14}=\frac{10}{21}+\frac{16}{35}=\frac{14}{15}\).

Ответ: 1) \(\frac{7}{29}\); 2) \(\frac{9}{58}\); 3) \(\frac{1}{2}\); 4) \(\frac{5}{9}\); 5) \(\frac{7}{27}\); 6) \(\frac{9}{22}\); 7) \(\frac{10}{33}\); 8) \(\frac{16}{39}\); 9) \(\frac{11}{21}\); 10) \(\frac{13}{45}\); 11) \(\frac{22}{63}\); 12) \(\frac{14}{15}\).