A
分析:此題可采用舉例驗證的方法解答,例如:
分母是3的所有最簡真分?jǐn)?shù)的和:
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=1;
分母是4的所有最簡真分?jǐn)?shù)的和:
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=1;
分母是5的所有最簡真分?jǐn)?shù)的和:
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=2;
分母是6的所有最簡真分?jǐn)?shù)的和:
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=1;
分母是7的所有最簡真分?jǐn)?shù)的和:
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=3;
分母是8的所有最簡真分?jǐn)?shù)的和:
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=2;
…
即使繼續(xù)增大分母,也能證明用同一個整數(shù)(大于2)做分母的所有最簡真分?jǐn)?shù)的和一定是整數(shù).
解答:由以上分析可知,用同一個整數(shù)(大于2)做分母的所有最簡真分?jǐn)?shù)的和一定是整數(shù).
故選:A.
點評:此題可采用舉例驗證的方法解答:用同一個整數(shù)(大于2)做分母的所有最簡真分?jǐn)?shù)的和一定是整數(shù).