13. 78% student was graduated from the school in 1980. 89% students graduated from the school in 1980. 问满足两个条件的学生比例。 这种题目的经典解释是:肉包子中a%是有摺的,有摺包子中b%是肉包子,实际上隐含的关系就是肉包子有摺的=有摺的肉包子,都是同一批包子(1980年毕业生的数目是一样的)..忘记是哪位NN在哪个月提出来的..拜服一下 变体题目(或者说本身就是原题):The sentence "students was graduated from high school" is accepted by 89% of the students, and the sentence ''students graduated from high school '' is accepted by 78% of the students. 问两个同时被accept的概率。70%
这道题不懂.怎么感觉上下两道题不是一回事?下面的变体题目是用89%*78%=69.42%得来的吗?
[此贴子已经被作者于2008-10-14 12:32:35编辑过] |