Объяснение:

1) 5/8 - 2/3 = 15/24 - 16/24 = -1/24

2) 2 1/3 : (-1/24) = 7/3 * (-24/1) = 7/1 * (-8/1) = -56/1 = -56

3) 2 * 1 3/7 = 2 * 10/7 = 20/7 = 2 6/7

4) -56 - 2 6/7 = -58 6/7