-3 3/5 + (-2 1/3) + 4 8/15 - 1 5/6 - (-6 7/10) + 1/2 =
= -18/5 + (-7/3) + 68/15 - 11/6 - (-67/10) + 1/2 =
= -18/5 - 7/3 + 68/15 - 11/6 + 67/10 +1/2 =
= -18*6/5*6 - 7*10/3*10 + 68*2/15*2 - 11*5/6*5 + 67*3/10*3 + 1*15/2*15 =
= -108/30 - 70/30 + 136/30 - 55/30 + 201/30 -15/30 =
= (-108-70+136-55+201-15)/30 = -89/30 = -2 целых 29/30
Ответ: - 2 целых 29/30.