题库搜索>问题求解PS-13418
A string of 10 lightbulbs is wired in such a way that if any individual lightbulb fails, the entire string fails. If for each individual lightbulb the probability of failing during time period T id 0.06, what is the probability that the string of lightbulbs will fail during time period T?
分析A选项
分析B选项
分析C选项
分析D选项
分析E选项
灯泡坏掉的概率等于1减去灯泡亮的概率
灯泡一直亮的概率是十盏灯每盏灯都亮着 也就是(1-0.06)^10
默默哒
楼上答案是错误的。 用正难则反来算:a string of 灯泡都坏,里面可能是一只坏,或两只坏,或三只坏....? 正的算比较难算。 所以要反着算:用1减去所有灯泡都是好的概率就是一串灯泡坏的概率(因为不管里面几只坏了,一串灯泡都是坏了) 所有灯泡都好的概率是(1-0.06)^10 所以答案应该是 E : 1-(0.94)^10
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问题求解PS
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GWD
1m50s
平均耗时
62.8%
平均正确率
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