After preliminary testing, it is determined that .01 of theresidents of Selma have a certain virus. In Sangrian, a suburb ofSelma (incidence of the virus is the same), the authorities testthe 10,000 residents of the suburb. The test has the followingcharacteristics. If you have the virus, the probability that thetest is positive is .95, and if you don’t have the virus, theprobability that the test is positive is .10. Suppose that 1,100 ofthe 10,000 residents test positive. Let X = the number among those1,100 who really do have the virus.
Find E(X) and Variance(X). thank you :) !!
