![](https://static.youtibao.com/asksite/comm/h5/images/m_q_title.png)
设工厂A和工厂B的产品的次品率分别为1%和2%,产品量分别占60%和40%,现从两厂的产品中随机抽取一件,发现是次
品,则该次品属A厂生产的概率是______.
![](https://static.youtibao.com/asksite/comm/h5/images/m_q_a.png)
设事件:A={抽取的产品为A工厂生产的};
事件:B={抽取的产品是B工厂生产的};
事件:C={抽取的是次品};
显然有:
P(A)=0.6;P(B)=0.4
P(C|A)=0.01;P(C|B)=0.02;
根据全概率公式有:
P(C)=P(A)P(C|A)+P(B)P(C|B)
=0.6×0.01+0.4×0.02
=0.014.
P(AC)=P(A)P(C|A)
=0.6×0.01
=0.006
根据条件概率公式有:
P(A|C)=
P(AC) |
P(C) |
3 |
7 |
故答案为:
3 |
7 |
![](https://static.youtibao.com/asksite/comm/h5/images/solist_ts.png)