Найди значение произведений 2/3×6/7,4/7×21/40,27/32×8/9,5/11×22/25,8/35×5/12, помогите...

Решите задачу:

$\frac{2}{3} \times \frac{6}{7} = \frac{4}{7} \\ \frac{4}{7} \times \frac{21}{40} = \frac{3}{10} \\ \frac{27}{32} \times \frac{8}{9} = \frac{3}{4} \\ \frac{5}{11} \times \frac{22}{25} = \frac{2}{5} \\ \frac{8}{35} \times \frac{5}{12} = \frac{2}{21}$