2целых2/3÷2+(4/15+2/5)÷(3целых1/3×3/5); 2÷1/4+((1целая1/2+2целых2/3)÷3целых3/4-2/3)÷8целых8/9

А) 2 2/3 : 2 + (4/15 + 2/5) : (3 1/3 * 3/5) = 8/3 * 1/2 + (4+6)/15 : (10/3 * 3/5) = 4/3 + 10/15 : 2 = 4/3 + 10/15 * 1/2 = 4/3 + 5/15 = (20+5)/15 = 25/15 = 1 10/15 = 1 2/3
б) 2 : 1/4 + ((1 1/2 + 2 2/3) : 3 3/4 - 2/3) : 8 8/9 = 2/1 * 4/1 + ((3/2 + 8/3) : 15/4) : 80/9 = 8 + ((9+16)/6 : 15/4) : 80/9 = 8 + (25/6 * 4/15) : 80/9 = 8 + (5/3*2/3) : 80/9 = 8 + 10/9 * 9/80 = 8 + 1/8 = 8 1/8