你好!
1/2÷4/5÷(2/9×3/8)
=1/2÷(2/9×3/8)÷4/5
=1/2*1/(2/9×3/8)*5/4
=5/2*(2/9×3/8)*4
=5÷(2/3)
=7.5
(5/6-3/4)÷5/12÷9/5
= (5/6-3/4)*12/5*5/9
=1/5*5/9
=1/9
3/7÷[5/7-(3/7+1/5)]
=3/7÷[5/7-3/7-1/5]
=3/7÷(2/7-1/5)
=3/7*1/(2/7-1/5)
=3/7*(2/7-1/5)
=3÷3/5
=5
希望对你有帮助,有不懂得还可以问我,祝你在以后的学习中更上一层楼!O(∩_∩)O~
5/9 与3/7之间是什么运算符 不问了,看来是三道
只有自己动脑 才能真正的会