问题 解答题
解方程
5
2
5
x-120%x=6.5
4x+0.4x=70.43x+90%×4=9(1+40%)x=98.
答案

(1)5

2
5
x-120%x=6.5,

4.2x=6.5,

4.2x÷4.2=6.5÷4.2,

x=

65
42

(2)4x+0.4x=70.4,

4.4x=70.4,

4.4x÷4.4=70.4÷4.4,

x=16;

(3)3x+90%×4=9,

3x+3.6=9,

3x+3.6-3.6=9-3.6,

3x=5.4,

3x÷3=5.4÷3

x=1.8;

(4)(1+40%)x=98,

1.4x=98,

1.4x÷1.4=98÷1.4,

x=70.

单项选择题
单项选择题