5.335 Приведите к несократимой дроби: a) \(\frac{2\cdot7}{6\cdot5}\), \(\frac{3\cdot5}{7\cdot3}\), \(\frac{9\cdot4}{4\cdot7}\), \(\frac{11\cdot5}{3\cdot11}\); б) \(\frac{4\cdot3}{7\cdot8}\), \(\frac{2\cdot3}{3\cdot10}\), \(\frac{21\cdot6}{21\cdot7}\), \(\frac{3\cdot7}{21\cdot24}\).

a) \(\frac{2\cdot7}{6\cdot5} = \frac{2\cdot7}{2\cdot3\cdot5} = \frac{7}{3\cdot5} = \frac{7}{15}\)

\(\frac{3\cdot5}{7\cdot3} = \frac{5}{7}\)

\(\frac{9\cdot4}{4\cdot7} = \frac{9}{7}\)

\(\frac{11\cdot5}{3\cdot11} = \frac{5}{3}\)

б) \(\frac{4\cdot3}{7\cdot8} = \frac{4\cdot3}{7\cdot4\cdot2} = \frac{3}{7\cdot2} = \frac{3}{14}\)

\(\frac{2\cdot3}{3\cdot10} = \frac{2}{10} = \frac{1}{5}\)

\(\frac{21\cdot6}{21\cdot7} = \frac{6}{7}\)

\(\frac{3\cdot7}{21\cdot24} = \frac{3\cdot7}{3\cdot7\cdot24} = \frac{1}{24}\)

Ответ: a) \(\frac{7}{15}\), \(\frac{5}{7}\), \(\frac{9}{7}\), \(\frac{5}{3}\); б) \(\frac{3}{14}\), \(\frac{1}{5}\), \(\frac{6}{7}\), \(\frac{1}{24}\)