问题 解答题
化简下列各分数.
3
9
=
12
18
=
21
35
=
15
20
=
30
45
=
28
98
=
答案

3
9
=
3÷3
9÷3
=
1
3
;                  
12
18
=
12÷6
18÷6
=
2
3
;                    
21
35
=
21÷7
35÷7
=
3
5

15
20
=
15÷5
20÷5
=
3
4
;                    
30
45
=
30÷15
45÷15
=
2
3
;                   
28
98
=
28÷14
98÷14
=
2
7

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