Сокращение выражений

1. $$\frac{9 \times 16}{8 \times 27} = \frac{9 \times 2 \times 8}{8 \times 3 \times 9} = \frac{2}{3}$$
2. $$\frac{8 \times 28}{35 \times 12} = \frac{8 \times 4 \times 7}{5 \times 7 \times 3 \times 4} = \frac{8}{15}$$
3. $$\frac{2 \times 3 \times 5}{4 \times 9 \times 25} = \frac{2 \times 3 \times 5}{2 \times 2 \times 3 \times 3 \times 5 \times 5} = \frac{1}{3 \times 5 \times 2} = \frac{1}{30}$$
4. $$\frac{7 \times 13 - 7 \times 2}{35 \times 9 + 35 \times 2} = \frac{7 \times (13 - 2)}{35 \times (9 + 2)} = \frac{7 \times 11}{35 \times 11} = \frac{7 \times 11}{5 \times 7 \times 11} = \frac{1}{5}$$