问题 填空题

在某次模拟考试中,某校1000名考生的数学成绩近似服从正态分布N(120,100),则该校数学成绩在140分以上的考生人数约为______.(注:若ξ~N(μ,σ2),则P(μ-2σ<ξ<μ+2σ)=0.954)

答案

∵数学成绩近似地服从正态分布N(120,102),P(|x-μ|<2σ)=0.9544,

∴P(|x-120|<20)=0.9544,

∴数学成绩在140分以上的考生人数约为

1
2
(1-0.9544)×1000≈23

故答案为23.

阅读理解

阅读理解。

     Sichuan (China Daily)-The beginning of 2007 will see another mass of graduates fresh from the campus

hunting for jobs.

     Sichuan University has done something special to help its graduates. One morning last month, a lady

stopped her Porsche (保时捷豪华跑车) in front of the students' canteen (食堂). She stepped out of her

expensive car and began to polish shoes for the students who were passing by. Later it was discovered that

she was a special lecturer who had been invited to talk to students on career development.

     Li Hui, 42, started from scratch (白手起家) in 1998 and has expanded her shoe-polishing service from

a single one-person stand on a street to a chain of 2,000 stands that operate in supermarkets, hotels and office

buildings.

     Li Hui said, "Apart from the existing and advertised job opportunities, there are plenty of other ways that

people can try to make money. There is nothing ignoble if you are doing an off-line business on your own,

such as car washing, house cleaning, shoe polishing, etc."

     It is to be hoped that such a successful grassroots woman as Li Hui will give the coming rush of job

hunters an insight into the job market in another way.

1. According to the passage, Li Hui is a _____. [ ]

A. canteen manager

B. university teacher

C. businesswoman

D. taxi driver

2. Why did Li Hui polish shoes for the students?  [ ]

A. To earn money from them.

B. To show the students how to polish shoes.

C. To set an example to job-hunting graduates.

D. To show that shoe polishing is quite an easy job.

3. The students can learn from what Li Hui said that _____. [ ]

A. no job is hard if you have a will to do it

B. women can be successful in all careers as men

C. everyone can be rich and famous through hard work

D. there are plenty of opportunities to succeed for everyone

4. What would be the best title for the news report? [ ]

A. A Successful Woman

B. A Rich Shoe-Polisher

C. Off-Line Jobs Help Make More Money

D. Self-Employment-A New Way Out for Job Hunters

单项选择题