题干

司机在开机动车时使用手机是违法行为,会存在严重的安全隐患,危及自己和他人的生命.为了研究司机开车时使用手机的情况,交警部门调查了100名机动车司机,得到以下统计:在55名男性司机中,开车时使用手机的有40人,开车时不使用手机的有15人;在45名女性司机中,开车时使用手机的有20人,开车时不使用手机的有25人.
(Ⅰ)完成下面的2×2列联表,并判断是否有99.5%的把握认为开车时使用手机与司机的性别有关;

开车时使用手机

开车时不使用手机

合计

男性司机人数

女性司机人数

合计

(Ⅱ)以上述的样本数据来估计总体,现交警部门从道路上行驶的大量机动车中随机抽检3辆,记这3辆车中司机为男性且开车时使用手机的车辆数为X,若每次抽检的结果都相互独立,求X的分布列和数学期望E(X).
参考公式与数据: Χ2=
n
(
a
d
−
b
c
)
2
(
a
+
b
)
(
c
+
d
)
(
a
+
c
)
(
b
+
d
)
,其中n=a+b+c+d.

P(Χ2≥k0)

0.150

0.100

0.050

0.025

0.010

0.005

0.001

k0

2.072

2.706

3.841

5.024

6.635

7.879

10.828

上一题 下一题 0.0难度 选择题 更新时间:2018-12-17 06:09:03

答案(点此获取答案解析)

解:(Ⅰ)填写2×2列联表,如下;

开车时使用手机

同类题1

根据短文理解,选择正确答案。

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