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Pascal

An electronic assembly is subjected to a final functional test.Suppose that defects occur at random in these assemblies， and that defects occur according to a poisson distribution with parameter np=0.02
i）what is the probability that an assembly will have exactly one defect.
ii) what is the probability that an assembly will have one or more defects.
iii)suppose that you improve the process so that the occurrence rate of defects is reduced to np=0.01. what effects does this have on the probability that an assembly will have one or more defects.

我知道这题很简单，不过在下恳请各位帮忙给下答案。尤其是第2 和第3 的。第3 到底是问些什么，thank you

puangenlun

An electronic assembly is subjected to a final functional test.
Suppose that defects occur at random in these assemblies,
and that defects occur according to a poisson distribution with parameter np=0.02
i）What is the probability that an assembly will have exactly one defect.
P(X=1)=e^(-0.02)*0.02^1/1!
ii) What is the probability that an assembly will have one or more defects.
1-P(X=0)
iii) Suppose that you improve the process so that the occurrence rate of defects is reduced to np=0.01.
What effects does this have on the probability that an assembly will have one or more defects.
1-P(X=0)

Pascal

多谢回复，不过可以劳烦你一下可以讲解一下第二和第三题吗？
第二题的答案就是把1 减掉第一题的答案就行了?

Batultu

lamda = np
k =x

puangenlun

第二题跟第三题是一样的
只是它们的参数变化罢了

第二题要求找到有问题的概率
P(有问题)=1-P(没问题)

Pascal

多谢各位帮忙