8 17/20-(4 17/30+ 1 14/15)=

2 7/20

Пошаговое объяснение:

8 17/20 - (4 17/30 + 1 14/15) = 2 7/20

1) 4 17/30 + 1 14/15 = 4 17/30 + 1 28/30 =5 45/30 = 6 15/30 = 6 1/2

2) 8 17/20 - 6 1/2 = 8 17/20 - 6 10/20 = 2 7/20