以下是引用cloverdream在2006-10-10 22:57:00的发言:45.科学家在研究一群侯鸟geese,30%male。During the scientific exp.eriment some geese migrated, and 20% of them were male. 问, what is the ratio of the migrating rate for male geese to the migrating rate for feel male geese? 题目给了个公式 the migrating rate for a certain sex=the number of geese of that sex which migrated during the experiment/ the total number of geese of that sex 楼主是这个题吧 条件好像差不多的,就是把geese 改成bird了,然后把ratio改成类似这样的表述“公鸟中,迁徙的鸟与所有的鸟的数量比”,还将这个比值定为X,再定义母鸟的Y 答案不记得了,我只看了这个月30题左右的数学JJ,没遇到过这题,所以不好意思,回忆错了 不希望误导大家,已经把回忆改过来了,尽量准确
[此贴子已经被作者于2006-10-10 23:28:38编辑过] |