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总共有12种生肖,复式选出5个一组,可以有4个重复。如果每个生肖都只选,那么组合数为:C(12,5) = 792如果有生肖重复4次,那么先在12个生肖中选1个,再在剩下的11个生肖中选4个,组合数为:C(12,1) × C(11,4) = 12 × 330 = 3,960如果有两个生肖重复2次,那么先在12个生肖中选2个,再在每组中各选2个,组合数为:C(12,2) × (C(4,2))^2 = 66 × 36 = 2,376如果有生肖重复3次,另生肖重复2次,那么先在12个生肖中选2个,再在第生肖中选3个,第二个生肖中选2个,组合数为:C(12,2) × C(5,3) × C(4,2) = 66 × 10 × 6 = 3,960所以,总共的组合数为:792 + 3,960 + 2,376 + 3,960 = 11,088。