4/7×3/5+3/7÷5/3
=4/7×3/5+3/7×3/5
=3/5×（4/7+3/7）
=3/5×1
=3/5
3.72-4/9+2.28-5/9
=3.72+2.28-4/9-5/9
=6-1=5