Ответ:

Пошаговое объяснение:

1) 15. 3/14 - 7. 4/35 = 15. 15/70 - 7. 8/70 = 8. 7/70 = 8. 1/10

2) 1. 1/9 + 2. 5/70 = 1. 70/630 + 2. 9/630 = 3. 79/630

3) 8. 1/10 * 3. 79/630 =

81/10 * 1969/630 = 17721/700 = 25. 221/700