Ответ: — 4 5/7+(-1 6/7) = — 33/7 — 13/7=-46/7= -6  4/7-4/5+(-4/7) = -4/5 — 4/7= -28/35 — 20/35= -48/35 = -1 13/35 -5/18+(-4/45) = -5/18 — 4/45= -25/90-8/90= — 33/90=-11/30 -4 9/14+(-3 4/21) = — 65/14 — 67/21= — 195/42 — 134/42=-329/42= — 7 35/42 = -7 5/6