1. Сократите дроби: 28. 8. 39.9×14. 35' 12' 12' 12' 28x3'

1. Сократите дроби: \(\frac{28}{35} = \frac{4 \cdot 7}{5 \cdot 7} = \frac{4}{5}\) \(\frac{8}{12} = \frac{2 \cdot 4}{3 \cdot 4} = \frac{2}{3}\) \(\frac{39}{12} = \frac{3 \cdot 13}{3 \cdot 4} = \frac{13}{4} = 3\frac{1}{4}\) \(\frac{9 \times 14}{12 \times 28 \times 3} = \frac{9 \times 2 \times 7}{12 \times 4 \times 7 \times 3} = \frac{9 \times 2}{12 \times 4 \times 3} = \frac{3 \times 3 \times 2}{3 \times 4 \times 4 \times 3} = \frac{2}{16} = \frac{1}{8}\)