问题 解答题
求未知数x
1
8
x-1=0.2x:
5
14
=21:
5
8
x-
1
8
x=21.
答案

(1)

1
8
x-1=0.2,

1
8
x-1+1=0.2+1,

1
8
x÷
1
8
=1.2÷
1
8

x=9.6;

(2)x:

5
14
=21:
5
8

5
8
x=21×
5
14

5
8
x÷
5
8
=
15
2
÷
5
8

x=12;

(3)x-

1
8
x=21,

7
8
x÷
7
8
=21÷
7
8

x=24.

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