一个分数的分子和分母的差是21，约分后是 25 。原来这个分数是多少？_刷题宝

题干

一个分数的分子和分母的差是21，约分后是

2

5

。原来这个分数是多少？

上一题下一题 0.0难度选择题更新时间:2019-11-05 09:38:30

答案(点此获取答案解析）

解：5-2=3
21÷3=7

$\frac{2 \times 7}{5 \times 7} = \frac{14}{35}$

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