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If 2 different representatives are to be selected at random from a group of 10 employees and if p is the probability that both representatives selected will be women, is p > ? (1) More than 1/2 of the 10 employees are women. (2) The probability that both representatives selected will be men is less than 1/10.
答案给的B。我觉得是E吧。。是不是错了?? 设女生员工数是X,男生为Y。概率为P (1)中设10人当中有6个是女的,则p=6/10 * 5/9<1/2 所以错。 (2)用同样的方法可知,男生不会多于3个。所以女生至少有7个。用女生为7带入算后发现仍然小于1/2,。所以(2)也肯定错吧。。答案怎么会是B呢??
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