英语翻译When doing blood testing for a viral infection,the procedure can be made more efficient and less expensive by combining partial samples of different blood specimens.If samples from five people are combined and the mixture tests negative,w

英语翻译When doing blood testing for a viral infection,the procedure can be made more efficient and less expensive by combining partial samples of different blood specimens.If samples from five people are combined and the mixture tests negative,w
英语翻译
When doing blood testing for a viral infection,the procedure can be made more efficient and less expensive by combining partial samples of different blood specimens.If samples from five people are combined and the mixture tests negative,we know that all five individual samples are negative.Find the probability of a positive result for five samples combined into one mixture,assuming the probability of an individual blood sample testing positive for the virus is 0.07.

英语翻译When doing blood testing for a viral infection,the procedure can be made more efficient and less expensive by combining partial samples of different blood specimens.If samples from five people are combined and the mixture tests negative,w
1 - 0.07 = 0.93 (probability of an individual blood sample testing negative for the virus)
0.93 x 0.93 x 0.93 x 0.93 x 0.93 = 0.6957 (probability of all 5 individual samples are negative)
1 - 0.6957 = 0.3043 (as long as 1 individual sample is positive,all 5 will be positive)
这题其实是很基础的统计学应用题.首先要懂得题意.如果五个取样混合都是阴性,那么 我们知道五个样本单独都是阴性.换句话说,只要五个样本单独有一个是阳性,那么五个取样混合就会是阳性.所以要解这题,首先要找出五个人全部都是阴性的几率,然后用100%减去全部阴性的几率,就得到其中任何一个或几个是阳性的几率了.

the probability of an individual blood sample testing positive for the virus is 0.07, which meant that the probability of an individual sample testing NEGATIVE is 1 - 0.07 = 0.93.
The probability ...

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the probability of an individual blood sample testing positive for the virus is 0.07, which meant that the probability of an individual sample testing NEGATIVE is 1 - 0.07 = 0.93.
The probability of all 5 samples testing NEGATIVE is 0.93⁵ = 0.70, so the probability of a positive result for five samples combined into one mixture is 1 - 0.70 = 0.30

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1-(1-0.07)^5=0.3043

根据旋转和对称的积分曲线，x + y的在I，III象限点0，二，四象限的分数为0，
所以原来的= 0
解决方法：根据积分曲线的参数方程X = COS，=SINθ0 <= THETA <2P
X'=SINθ，Y'= COS
DS =√[（X'）^ 2 +（ y'）的^ 2]Dθ=Dθ
（+ y）的DS =（SINθ+COSθ）Dθ代入的正交= 0。...

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根据旋转和对称的积分曲线，x + y的在I，III象限点0，二，四象限的分数为0，
所以原来的= 0
解决方法：根据积分曲线的参数方程X = COS，=SINθ0 <= THETA <2P
X'=SINθ，Y'= COS
DS =√[（X'）^ 2 +（ y'）的^ 2]Dθ=Dθ
（+ y）的DS =（SINθ+COSθ）Dθ代入的正交= 0。

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