问题 解答题
解化例.
3
5
:x=
1
3
:2      
8
21
=
0.4
x
x:6.4=4:3.25     
1.25
0.25
=
x
1.6
答案

(1)

3
5
:x=
1
3
:2,

1
3
x=
3
5
×2,

1
3
x÷
1
3
=
6
5
÷
1
3

x=

18
5

(2)

8
21
=
0.4
x

8x=21×0.4,

8x÷8=8.4÷8,

x=1.05;

(3)x:6.4=4:3.25,

3.25x=4×6.4,

3.25x÷3.25=25.6÷3.25,

x=

512
65

(4)

1.25
0.25
=
x
1.6

0.25x=1.6×1.25,

0.25x÷0.25=2÷0.25,

x=8.

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