Ответ:
- \(\frac{6}{11}\cdot\frac{4}{7}=\frac{24}{77}\).
- \(\frac{7}{20}\cdot\frac{10}{21}=\frac{1}{6}\).
- \(\frac{8}{9}\cdot\frac{27}{32}=\frac{3}{4}\).
- \(\frac{23}{28}\cdot\frac{49}{46}=\frac{23}{24}\).
- \(\frac{34}{86}\cdot\frac{43}{51}=\frac{1}{3}\).
- \(\frac{7}{18}\cdot\frac{90}{77}=\frac{5}{11}\).
- \(\frac{63}{64}\cdot\frac{48}{91}=\frac{9}{16}\).
- \(\frac{19}{100}\cdot\frac{5}{38}=\frac{1}{40}\).
Ответ: 1) \(\frac{24}{77}\); 2) \(\frac{1}{6}\); 3) \(\frac{3}{4}\); 4) \(\frac{23}{24}\); 5) \(\frac{1}{3}\); 6) \(\frac{5}{11}\); 7) \(\frac{9}{16}\); 8) \(\frac{1}{40}\).
