- 问题求解从1分、2分、5分及1角的4枚硬币中,至少任取1枚,可以组成不同币值的种数是()。
- A 、10
- B 、12
- C 、13
- D 、14
- E 、15
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参考答案
【正确答案:E】
用加法原理,正好取一枚的币值种数为4,正好取两枚的币值种数为正好取三枚的币值种数为正好取四枚的币值种数为
从而不同种的币值种数共有4+6+4+1=15(种).
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