A: 8/3 - 5/3 × 7/3
= 8/3 - 5×7/3×3
= 8/3 - 35/9
= 8×3/3×3 - 35/9
= 24/9 - 35/9
= -11/9
B: (2+2/3) ÷ (4/5-2/3)
= (2×3/1×3+2/3) ÷ (4×3/5×3-2×5/3×5)
= (6/3+2/3)÷(12/15-10/15)
= (8/3) ÷ (2/15)
= (8/3) × (15/2)
= (8×2/3×2) × (15×3/2×3)
= (16/6) × (45/6)
= 720/6
= 120
et voilà !! j'espère que ça t'aide :-)