问题 解答题
求未知数X
1
3
÷X=
3
8

X
8
-14.5=5.5
1.1×4-2.2X=0
2
3
1
3
=X:8.
答案

(1)

1
3
÷x=
3
8

1
3
÷x×x=
3
8
x,

3
8
x=
1
3

3
8
8
3
=
1
3
×
8
3

x=

8
9

(2)

x
8
-14.5=5.5,

x
8
-14.5+14.5=5.5+14.5,

x
8
×8=20×8,

x=160;

(3)1.1×4-2.2x=0,

4.4-2.2x=0,

4.4-2.2x+2.2x=2.2x,

2.2x÷2.2=4.4÷2.2,

x=2;

(4)

2
3
1
3
=x:8,

1
3
x=
2
3
×8,

1
3
x×3=
16
3
×3,

x=16.

单项选择题
单项选择题