[中學] 一題排列組合
4對夫婦排一列
男女間隔沏夫婦不相鄰 有幾種排法?
我的算法如下:
男女相間+錯排
2*(4!*4!-4*3!*3!+6*2!*2!-4*1!*1!+1*0!*0!)=906
可是答案卻是144
我的作法哪裡錯了?
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推
07/14 16:53, , 1F
07/14 16:53, 1F
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07/14 18:04, , 2F
07/14 18:04, 2F
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07/14 18:04, , 3F
07/14 18:04, 3F
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07/14 18:05, , 4F
07/14 18:05, 4F
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07/14 18:06, , 5F
07/14 18:06, 5F
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07/14 18:06, , 6F
07/14 18:06, 6F
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07/14 18:06, , 7F
07/14 18:06, 7F
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07/14 18:07, , 8F
07/14 18:07, 8F
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07/14 18:07, , 9F
07/14 18:07, 9F
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07/14 18:07, , 10F
07/14 18:07, 10F
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07/14 18:12, , 11F
07/14 18:12, 11F
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07/14 18:13, , 12F
07/14 18:13, 12F
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07/14 18:14, , 13F
07/14 18:14, 13F
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07/14 18:15, , 14F
07/14 18:15, 14F
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