5.388 Сократите дроби \(\frac{10}{12}\), \(\frac{39}{45}\), \(\frac{75}{125}\), \(\frac{21}{70}\), а потом приведите к знаменателю 30.

Сократим дроби:

1. \(\frac{10}{12} = \frac{5 \cdot 2}{6 \cdot 2} = \frac{5}{6}\)
2. \(\frac{39}{45} = \frac{13 \cdot 3}{15 \cdot 3} = \frac{13}{15}\)
3. \(\frac{75}{125} = \frac{3 \cdot 25}{5 \cdot 25} = \frac{3}{5}\)
4. \(\frac{21}{70} = \frac{3 \cdot 7}{10 \cdot 7} = \frac{3}{10}\)

Приведем полученные дроби к знаменателю 30:

1. \(\frac{5}{6} = \frac{5 \cdot 5}{6 \cdot 5} = \frac{25}{30}\)
2. \(\frac{13}{15} = \frac{13 \cdot 2}{15 \cdot 2} = \frac{26}{30}\)
3. \(\frac{3}{5} = \frac{3 \cdot 6}{5 \cdot 6} = \frac{18}{30}\)
4. \(\frac{3}{10} = \frac{3 \cdot 3}{10 \cdot 3} = \frac{9}{30}\)

Ответ: \(\frac{25}{30}\), \(\frac{26}{30}\), \(\frac{18}{30}\), \(\frac{9}{30}\)