题干

李老师要对初三(1)、(2)班的考试情况进行分析,在两个班里随机抽取了30名学生的考试成绩:87、75、94、60、51、86、73、89、93、67、57、88、82、66、88、88、85、67、91、65、78、89、80、72、78、84、90、64、71、86.

根据上述消息回答下列问题:

(2)估计这两个班级本次考试成绩在80分及80分以上的占____ %;

(4)是否一定能根据这30名学生的成绩估计全区考试成绩?答:____ .

(5)80~90组的平均分为____ ,中位数为____ .

上一题 下一题 0.0难度 选择题 更新时间:2018-01-03 12:19:28

答案(点此获取答案解析)

53.3,不一定,86.5,86

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阅读短文, 从每题所给选项中选出可以填入空白处的最佳选项。

    When I was a junior high school student in 1980, God gave me a gift, it was happiness.

    One weekend, I went to visit my grandparents in the countryside. On my way home a car ran over me and cut off my1because of its high speed.

    Several days later when I woke up at the hospital, I realized I had to spend the rest of my life2arms. How sad I felt at that time! Even I was full of fears.3slowly I knew I had to face the fact and got over it. I couldn't get my arms back even though I4every day.

    However, it's easier to5than to do. It6me nearly half a year to get out of the sadness completely. I got so much from my7story. From then on, I could treat my life with a normal(正常的) mind. But in our daily life, I often see my classmates get8about little things: They get a bad grade on a test; their bus comes9; they don't have a mobile phone but10have, and so on. But I only11life. I was lucky to realize from an accident: It is a waste of our life to focus on(关注)what you have12. We should always think of what we have. So why are so many people unhappy? Someone may say, “My whole life would improve13I have a new car.” But when you get the car and what14? For a whole week you are walking on air. Then you go right back to being unhappy.

    Happiness depends on(取决于) what we have! It's in our heart. It's a state of mind, even though you own the whole world, you may still feel15.Happiness comes from mastering the art of appreciating(感激) and taking pleasure in what you really have.