1、可以这样做:郑或型
3/4×〔2/9+(9/10-2/5)÷3/10〕
=3/4×〔2/9+(9/10-4/10)x10/3〕
=3/4×(2/9+5/10×10/3)
=3/4×(2/9+15/9)
=3/4×17/9
=17/喊猜12
2、这题没有团瞎简便算法,只能按加减乘除的规则一步一步来。
3/4×〔2/9+(9/山闷漏10-2/5)逗烂÷3/10〕
=3/罩汪4×〔2/9+(9/10-4/10)÷3/10〕
=3/4×(2/9+5/10×10/3)
=3/4×(2/9+15/9)
=3/4×17/9
=17/12
3/4×[2/9+(9/茄裂10一2/哗液5)÷3/颤芦闭10]
=3/4×[2/9+1/2x10/3]
=3/4x[2/9+5/3]
=3/4x17/9
=17/12