问题 解答题
化简比.
3
7
5
21
7.5:0.75      
3
4
8
15
答案

3
7
5
21

=(

3
7
×21):(
5
21
×21),

=9:5;

7.5:0.75,

=(7.5×100):(0.75×100),

=750:75,

=(750÷75):(75÷75),

=10:1;

3
4
8
15

=(

3
4
×60):(
8
15
×60),

=45:32.

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