请教排列组合题:五张卡片上分别写上字母,E,E,B,B,B,将五张卡片随机地排成一行...

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  • BEBEB:(3/5)*(2/4)*(2/3)*(1/2)=1/10

    BBBEE?(3/5)(2/4)(1/3)=1/10