Вычислите: а) 3/51 · 5; б) 5/34 · 6; в) 4/50 · 3; г) 8/28 · 4; д) 8/14 · 6; е) 7/8 · 11; ж) 9/11 · 100; з) 2/35 · 7; и) 4/27 · 10; к) 1 3/14 · 4; л) 7/9 · 6; м) 11/8 · 4; н) 7/8 · 33; о) 13/121 · 5/11.

1. \(\frac{3}{51}\cdot5=\frac{15}{51}=\frac{5}{17}\);
2. \(\frac{5}{34}\cdot6=\frac{30}{34}=\frac{15}{17}\);
3. \(\frac{4}{50}\cdot3=\frac{12}{50}=\frac{6}{25}\);
4. \(\frac{8}{28}\cdot4=\frac{32}{28}=\frac{8}{7}=1\frac{1}{7}\);
5. \(\frac{8}{14}\cdot6=\frac{48}{14}=\frac{24}{7}=3\frac{3}{7}\);
6. \(\frac{7}{8}\cdot11=\frac{77}{8}=9\frac{5}{8}\);
7. \(\frac{9}{11}\cdot100=\frac{900}{11}=81\frac{9}{11}\);
8. \(\frac{2}{35}\cdot7=\frac{14}{35}=\frac{2}{5}\);
9. \(\frac{4}{27}\cdot10=\frac{40}{27}=1\frac{13}{27}\);
10. \(1\frac{3}{14}\cdot4=\frac{17}{14}\cdot4=\frac{34}{7}=4\frac{6}{7}\);
11. \(\frac{7}{9}\cdot6=\frac{42}{9}=\frac{14}{3}=4\frac{2}{3}\);
12. \(\frac{11}{8}\cdot4=\frac{44}{8}=\frac{11}{2}=5\frac{1}{2}\);
13. \(\frac{7}{8}\cdot33=\frac{231}{8}=28\frac{7}{8}\);
14. \(\frac{13}{121}\cdot\frac{5}{11}=\frac{65}{1331}\).

Ответ: \(\frac{5}{17};\ \frac{15}{17};\ \frac{6}{25};\ 1\frac{1}{7};\ 3\frac{3}{7};\ 9\frac{5}{8};\ 81\frac{9}{11};\ \frac{2}{5};\ 1\frac{13}{27};\ 4\frac{6}{7};\ 4\frac{2}{3};\ 5\frac{1}{2};\ 28\frac{7}{8};\ \frac{65}{1331}\).