0.75过程直接写上就好了呀这是简便题3/4×8/9+3/4÷9 =3/4×8/9+3/4×1/9 =3/4×﹙8/9+1/9﹚ =3/4×1 =3/4你有CF号吗？没6/5-12/7x14/15？也是简便？