问题 选择题

今年某市约有5.2万学生参加初中毕业会考,为了解这5.2万名学生的数学成绩,

从中抽取1000名考生的数学成绩进行统计分析,以下说法正确的是               (  )

A.1000名学生是样本容量

B.5.2万名考生是总体

C.这1000名考生是总体的一个样本

D.每位考生的数学成绩是个体

答案

答案:D

分析:总体是指考查的对象的全体,个体是总体中的每一个考查的对象,样本是总体中所抽取的一部分个体,而样本容量则是指样本中个体的数目.我们在区分总体、个体、样本、样本容量,这四个概念时,首先找出考查的对象.从而找出总体、个体.再根据被收集数据的这一部分对象找出样本,最后再根据样本确定出样本容量.

解答:解:A、1000是样本容量,故本选项错误;

B、5.2万名考生的数学成绩是总体,故本选项错误;

C、1000名考生的成绩是总体的一个样本,故本选项错误;

D、每位考生的数学成绩是个体,故本选项正确.

故选D.

阅读理解

阅读理解。

     Dr. Glenn Tisman, a cancer specialist, knew his young neighbor, Ray Bateman, had an unusual mind.

But he had no idea at the time that 12-year-old Ray had the ability to become his partner in cancer

research.

     Ray' s parents remembered that at age four, Ray surprised them by fixing a broken vacuum cleaner (吸

尘器). When he was ten, he speedily constructed the family color television from a kit.Later, he

succeeded in assembling (组装) a complex stereo system after two experts had failed to do the job.

     When Ray was ten, he convinced his parents to buy him a computer.In a short time, Ray was able to

do amazing things with the computer.Ray shared his enthusiasm for computers with Dr. Tisman, who

used a computer for his research. The two discussed computers and medicine frequently.Amazingly, Ray

understood the biology and chemistry related to Dr. Tisman's medical research without any previous

instruction.

     Ray then worked with Dr. Tisman after school.He helped conduct research with the equipment and

kept it in working order.The purpose of the research was to test the effectiveness of mixing an old cancer

drug with certain vitamins.Ray analyzed patient test results by computer, while Dr. Tisman handled all

patient contact.Together, they came up with solid research that helped advance cancer treatment.

     In 1988, 14-year-old Ray went with Dr. Tisman to a meeting of the American Federation for Clinical

Research (AFCR) , where Ray presented their initial research findings.Using terminology (术语) beyond

the grasp of most kids of his age, Ray told the scientists how the new drug mixture caused fewer and

milder side effects for cancer patients.

     A year later, Ray returned to the meeting to update the findings of his and Dr. Tisman' s research. By

then, he had become well-known for his devotion to finding cures for sick patients.Stories about him

appeared in hundreds of newspapers around the world.He appeared on television newscasts and talk

shows.

     Ray continued to spend most free hours working with Dr. Tisman.The two began studying the effects

of vitamins on babies inside the womb.However, Ray' s main interest remained cancer treatment, and he

continues his research today.

1. According to the passage, Ray______.

A. is a boy of many gifts

B. is very helpful to his parents

C. learned fast under Dr. Tisman' s instruction

D. stopped working with Dr. Tisman after his success

2. What do we know about Dr. Tisman?

A. He succeeded in finding cures for cancer.

B. He made a new discovery in cancer treatment.

C. He convinced Ray to become a partner of him.

D. He taught Ray knowledge related to his research.

3. What made Ray first known to the medical world?

A. His presentation at AFCR.

B. His great skills in computer.

C. His devotion to cancer research.

D. His appearance on television newscasts.

4. Dr. Tisman's research is aimed at ______.

A. providing different cancer treatments

B. proving the effects of vitamins on babies

C. finding the side effects of a cancer drug

D. testing the effectiveness of a new drug mixture

单项选择题