Пошаговое объяснение:

1) -2 1/2 : 3 1/3 = -5/2 : 10/3 = -5/2 * 3/10 = -3/4

2) -14/3 * -6/7 = 4

3) 27/8 * -4/9 = -3/2 = -1 1/2

4) -15/2 * 4/15 = -2

5) -49/9 * -3/7 = 7/3 = 2 1/3

6) 28/3 * -9/56 = -3/2 = -1 1/2