给算式18.9*11.7-4.05/0.5填上适当的括号,使它们符合下面的运算顺序(1)减_除_乘 (2)除-减-乘(3)减-乘-除

问题描述:

给算式18.9*11.7-4.05/0.5填上适当的括号,使它们符合下面的运算顺序(1)减_除_乘 (2)除-减-乘(3)减-
乘-除

1.
18.9×[(11.7-4.05)÷0.5]
2.
18.9×(11.7-4.05÷0.5)
3.
18.9×(11.7-4.05)÷0.5