求解两道变体，男人女人和学历～

guyiyu1987

1.         DS，有255个人，抽出一个人为女人且有大学学历的概率小于1/2？

(1)    其中125个人有大学学历

(2)    其中130个人为男人

D

有的寂静是选E，个人觉得也是E。请问哪个是对的？

2.         一个公司里面有250人，有一部分的人是大学学位的，现在选一个人去开会，问选中是女人且有大学学位的概率是否<1/2?

1）有大学学位的人有125个

2）有女人一共130人

E

不清楚这两题有什么区别否。。。

guyiyu1987

顶！没人知道吗？？急！

我把GWD几道相关的也找出来了。

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 > 0.5?

(1)
                      More than half of the 10 employees are women.
                

(2)
                      The probability that both representatives selected will be men is less than 0.1.                

Answer: E

What is the probability that a student randomly selected from a class of 60 students will be a male who has brown hair?

(1)
                  One-half of the students have brown hair.

(2)
                  One-third of the students are males.

              

Answer: E

guyiyu1987

恩～这个极值法很有道理～