1/2÷4/5÷（稿虚2/9×3/8）=1/2 x 5/4 x9/2 x 8/3=5/8 x 8/3 x 9/2=5/3 x 9/键空燃亏颤2=15/2
1.1/2÷4/5÷（2/9×3/8） =1/2×5/4÷1/12=5/纤含8×12=15/缺神2=7.52.（5/6-3/4)÷5/12÷9/伏竖亏5 3/7÷[5/7-(3/7+1/5)]
= =好难算的样子
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