※ 引述《TCSSH ()》之铭言： : 6. : A patient takes a lab test and the result comes back either positive or : negative. The test returns a correct positive result in 99% of the cases in : which the disease is actually present, and a correct negative result in 98% : of the cases in which the disease is not present. Furthermore,0.001 of all : people have this cancer. : (a) If a person is tested positive, what is the probability that this person : has the cancer. : (b) If a person takes two independent tests and both return positive results. : What is the probability that this person has the cancer? : (c) If a person takes two independent tests and only one returns positive : result. What is the probability that this person has the cancer? : 我的算法是： : a). 0.1/100 x 99/100 =9.9/10000 : b). (0.1/100 x 99/100)+(0.1/100 x 99/100) =19.8/10000 : c). (0.1/100 x 99/100)+(0.1/100 x 2/100) = 10.1/10000 : 可以帮我看看我算的对不对吗 谢谢 如果我没会错题目意思的话, 答案应该如下. a). (0.001*99%)/(0.001*99%+0.999*2%) b). (0.001*99%*99%)/(0.001*99%*99%+0.999*2%*2%) c). (0.001*99%*1%)/(0.001*99%*1%+0.999*2%*98%) --

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