Ответ:

5

Пошаговое объяснение:

1) 6. 2/3 * 3/7 = 20/3 * 3/7 = 20/7 = 2. 6/7

2) 2. 6/7 + 3/4 =

2. 24/28 + 21/28 =

2. 45/28 = 3. 17/28

3) 3. 17/28 : 1/7 =

101/28 : 1/7 = 101/28 * 7/1 = 101/4 * 1/1 = 101/4 = 25. 1/4

4) 25. 1/4 - 20. 1/4 = 5