Пошаговое объяснение:
2/5×8-2/5×3а-1/2×4б-1/2×3=
16/5- 2/5×(3×11/3)-1/2×(4×3/11)-3/2= 16/5- 2/5×11-1/2×12/11-3/2= 16/5-22/5-6/11-3/2= -6/5-6/11-3/2= -36/55-3/2= -72/110-165/110= -237/110
