▪1 7/18-4/15 = 1 35/90 - 24/90 = 1 целая 11/90
▪4 4/5 × 4 1/6 = 24/5 × 25/6 = (24×25)/(5×6) = 4×5 = 20
▪3 1/9:4 2/3 = 28/9 ÷ 14/3 = 28/9 × 3/14 = (28×3)/(9×14) = (2×1)/(3×1) = 2/3
▪(30:27-1/3)*2 1/7+2/5 = (30/27-1/3) × 15/7 + 2/5 = (10/9-3/9) × 15/7 + 2/5 = 7/9 × 15/7 + 2/5 = 5/3 + 2/5 = 1 2/3 + 2/5 = 1 10/15 + 6/15 = 1 16/15 = 2 целых 1/15