Пошаговое объяснение:

1.

[tex]1 \frac{7}{15} \times \frac{25}{42} = \frac{22}{15} \times \frac{25}{42} = \frac{11}{3} \times \frac{5}{21} = \frac{55}{63} = 0.87[/tex]

2.

[tex] \frac{8}{25} \div \frac{2}{25} = \frac{8}{25} \times \frac{25}{2} = \frac{8}{2} = 4[/tex]