489.1) 2⋅3/5+3/5⋅2+1/2⋅6+6:1/2

2⋅3/5 = 6/5, 3/5⋅2 = 6/5, 1/2⋅6 = 3, 6:1/2 = 12. Сложение: 6/5 + 6/5 + 3 + 12 = 24/5 + 15 = 19,8