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调查作业:了解你所在小区家庭5月份用气量情况:

  小天、小东和小芸三位同学住在同一小区,该小区共有300户家庭,每户家庭人数在2﹣5之间,这300户家庭的平均人数均为3.4.

  小天、小东和小芸各自对该小区家庭5月份用气量情况进行了抽样调查,将收集的数据进行了整理,绘制的统计表分别为表1,表2和表3.

表1 抽样调查小区4户家庭5月份用气量统计表  (单位:m3)

家庭人数

2

3

4

5

用气量

14

19

21

26

表2 抽样调查小区15户家庭5月份用气量统计表 (单位:m3)

家庭人数

2

2

2

3

3

3

3

3

3

3

3

3

3

3

4

用气量

10

11

15

13

14

15

15

17

17

18

18

18

18

20

22

表3 抽样调查小区15户家庭5月份用气量统计表 (单位:m3)

家庭人数

2

2

2

3

3

3

3

3

3

4

4

4

4

5

5

用气量

10

12

13

14

17

17

18

19

20

20

22

26

31

28

31

根据以上材料回答问题:

小天、小东和小芸三人中,哪一位同学抽样调查的数据能较好地反映该小区家庭5月份用气量情况,并简要说明其他两位同学抽样调查的不足之处.

上一题 下一题 0.0难度 选择题 更新时间:2018-12-07 09:14:26

答案(点此获取答案解析)

解:小芸,小天调查的人数太少,小东抽样的调查数据中,家庭人数的平均值为:

(2×3+3×11+4)÷15=2.87,

远远偏离了平均人数的3.4,所以他的数据抽样有明显的问题,

小芸抽样的调查数据中,家庭人数的平均值为:(2×2+3×7+4×4+5×2)÷15=3.4,

说明小芸抽样数据质量较好,因此小芸的抽样调查的数据能较好的反应出该小区家庭5月份用气量情况.

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