Question 2 (10 points) Suppose the men attending a particular clinic show a long-term chance of 1 in 100 of having colon cancer. Suppose also that the initial screening test used at the clinic has a false positive rate of 0.2 (that is, 20% of men without cancer will test positive for cancer) and that it has a false negative rate of 0.1 (that is, 10% of men with cancer will test negative). The laws of probability dictate from this last fact that the probability of a positive test given cancer is 90%. Now suppose that you are such a man who has just tested positive. What is the probability that you have cancer?

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