问题 解答题
甲乙两个学校高三年级分别为1100人,1000人,为了统计两个学校在地区二模考试的数学科目成绩,采用分层抽样抽取了105名学生的成绩,并作出了部分频率分布表如下:(规定考试成绩在[120,150]内为优秀)
甲校:
分组[70,80)[80,90)[90,100)[100,110)[110,120)[120,130)[130,140)[140,150)
频数23101515x31
乙校:
分组[70,80)[80,90)[90,100)[100,110)[110,120)[120,130)[130,140)[140,150)
频数12981010y3
(1)计算x,y的值,并分别估计两上学校数学成绩的优秀率;
(2)由以上统计数据填写下面2×2列联表,并判断是否有97.5%的把握认为两个学校的数学成绩有差异.
 甲校乙校总计
优秀   
非优秀   
总计   
附:k2=
n(ad-bc)2
(a+b)(c+d)(a+c)(b+d)

P(k2≥k00.100.0250.010
k02.7065.0246.635
答案

(1)依题甲校抽取55人,乙校抽取50,

故x=6,y=7

估计甲校优秀率为

10
55
=18.2%

乙校优秀率为

20
50
=40%

(2)根据所给的条件列出列联表

 甲校乙校总计
优秀102030
非优秀453075
总计5550105
k2=
105×(10×30-20×45)2
55×50×30×75
=6.109

又因为6.10>5.024

故有97.5%的把握认为两个学校的数学成绩有差异.

阅读理解
阅读理解。
Films in Feiyang Cinema This Week
A WORLD WITHOUT THIEVES
 
·Chinese film(2004)
·Directed (导演)by Feng Xiaogang
·Mainly acted by Liu Dehua, Liu Ruoying, Ge You,
    Li Bingbing
·From Monday to Wednesday, at 8:00 p.m.
·Ticket Price: RMB 35.
KUNGFU HUSTLE
 
·Chinese Hong Kong film (2004)
·Directed by Zhou Xingchi
·Mainly acted by Zhou Xingchi, Yuan Hua, Liang
    Xiaolong
·From Wednesday to Friday, at 8:00 p.m.
·Ticket price: RMB 40
HARRY POTTER (Ⅲ)
 
·American film (2004)
·Directed by Alfonso Cuaron
·Mainly acted by Daniel Radcliffe, Rupert Grint,
    Emma Waston
·From Friday to Sunday, at 7:30 p.m
·Ticket Price: RMB 30 (Half on Sunday for children)
TROY
 
·American film (2004)
·Directed by Wolfgang Petersen
·Mainly acted by Julian Glover, Brian Cox,
    Nathan Jones, Adoni Maropis
·From Tuesday to Thursday, at 8:00 p.m
·Ticket Price: RMB 45

1. You can see _____ foreign films in Feiyang Cinema this week.
    A. one                  
    B. two                  
    C. three                
    D. four
2. If you want to see the film which was directed by Feng Xiaogang, go to the cinema on _____ .
    A. Monday        
    B. Thursday            
    C. Friday            
    D. Saturday
3. Children can pay only _____ when they want to see a film on Sunday.
    A. 5            
    B. 10                      
    C. 15            
    D. 20
4. You can see the film _____ on Saturday.
    A. Troy                                        
    B. Harry Potter
    C. A World Without Thieves              
    D. Kungfu Hustle
5. Which of the following is TRUE?
    A. Liu Dehua acted in the film Kungfu Hustle.
    B. The ticket price of the four films is the same.
    C. All the films start after 8 o'clock in the evening.
    D. The four films were released (发行) in the same year.
单项选择题