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An enzyme immunoassay (EIA) test can be used to screen blood specimens for the presence of antibodies to a new virus. If antibodies are detected, the patient has contracted the virus. The test is highly accurate but is not a perfect diagnostic tool. Consider a population of 2,000,000 patients that are to be tested with the EIA test. Assume that 1% of the population has contracted the new virus.

Among patients who the virus, the EIA test results will be correctly positive 97.2% of the time (true positives). Among patients who do not have the virus, the EIA test results will be correctly negative 99.4% of the time (true negatives). In the remaining (0.6% of cases, the tests will incorrectly diagnose the virus in patients who are not infected false positives).

Calculate the percentage of the population testing positive.

Calculate the percentage of people testing positive who ​have the virus.

Percentage of population with positive EIA test result

Percentage of people with positive EIA test who actually have the virus







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