【題目】甲、乙兩門高射炮同時(shí)向一敵機(jī)開炮，已知甲擊中敵機(jī)的概率為0.6，乙擊中敵機(jī)的概率為0.8，敵機(jī)被擊中的概率為________．

【答案】0.92

【解析】解法一：設(shè)“甲擊中敵機(jī)”為事件A，“乙擊中敵機(jī)”為事件B，事件A、B相互獨(dú)立，所以所求的概率為P＝P(A∩B)＋P(∩B)＋P(A∩)＝P(A)·P(B)＋P()·P(B)＋P(A)·P()＝0.6×0.8＋0.4×0.8＋0.6×0.2＝0.92.

解法二：利用對(duì)立事件的概率，P＝1－P(∩)＝1－P()·P()＝1－(1－0.6)(1－0.8)＝0.92.

解法三：敵機(jī)被擊中為事件A∪B，P(A∪B)＝P(A)＋P(B)－P(A∩B)＝P(A)＋P(B)－P(A)·P(B)＝0.6＋0.8－0.6×0.8＝0.92.

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