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【329820】6.4 数据的离散程度 同步练习3

时间:2025-02-05 18:10:16 作者: 字数:2979字


 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a>

数据的离散程度

数据的离散程度(1

一、选择题

1.下列说法正确的是( )

A.数据1,﹣135的极差是4

B.数据1,﹣135的方差是 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a>

C.数据1,﹣135的标准差是5

D.数据1,﹣135的方差是5

2.下列说法错误的是( )

A.极差越小越稳定 B.方差越小越稳定

C.标准差越小越稳定 D.以上都不对

3.已知一组数据abcde的方差是7,则另一组数据a+2b+2c+2d+2e+2的方差为( )

A5 B7 C10 D3

二、填空题

4.数据12345的方差s2=___________.

5.分别从甲、乙两厂各抽检了20只鸡腿,结果如图. 如果只考虑鸡腿的质量均匀程度,可以判断质量更稳定的是____________.

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a>

6.一同学计算数据x1x2,…,xn的方差,算到s2= <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> ,如果他的计算没有错,可知这组数据的平均数等于____________.

三、解答题

7.某校高中一年级组建篮球队,对甲、乙两名备选同学进行定位投篮测试,每次投10个球共投10次,甲、乙两名同学测试情况如图所示.请计算他们每次命中的平均数,众数,方差并给出你的选择.

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a>

数据的离散程度(2

一、选择题

1.甲、乙在相同的条件下各射靶10次,他们的环数的方差是 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> ,则射击稳定性是( )

A.甲高 B.乙高

C.两人一样多 D.不能确定

2.若一组数据 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> ,…, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> 的方差是5,则一组新数据 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> ,…, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> 的方差是( )

A5 B10 C20 D50

3.数据7071727374的标准差是为( )

A <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> B2 C <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> D <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a>

二、填空题

4.随机从甲、乙两块试验田中各抽取100株麦苗测量高度,计算平均数和方差的结果为: <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a> ,则小麦长势比较整齐的试验田是___________.

5.样本数据36 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a>42的平均数是3,则这个样本的方差是____________.

6.若另一组数据的标准差是2,则方差是____________.

三、解答题

7.某校初三年级甲、乙两班举行电脑汉字输入比赛,两个班能参加比赛的学生每分钟输入汉字的个数,经统计的个数,经统计和计算后结果如下表:.

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/171/" title="数据" class="c1" target="_blank">数据</a> <a href="/tags/1408/" title="程度" class="c1" target="_blank">程度</a> <a href="/tags/1409/" title="离散" class="c1" target="_blank">离散</a>

有一位同学根据上面表格得出如下结论:

  1. 甲、乙两班学生的平均水平相同;

  2. 乙班优秀人数比甲班优秀人数多(每分钟输入汉字达150个以上为优秀);

  3. 甲班同学比赛成绩的波动比乙班学生比赛成绩的波动大.

上述结论正确的是____________.

参考答案

数据的离散程度(1

1D 2D 3B

42

5.甲

63

7.略


数据的离散程度(2

1A 2C 3A

42

54

64

7.①②③