A disease affects of a population. A test detects it in of the sick people and wrongly reacts in of healthy people. What is the probability that a person with a positive test is sick?
Answer and explanation
Correct answer: B. About
- Step 1: Positive and sick: ; positive and healthy: . Step 2. . **Answer: about . Why not the others:** confuses the test sensitivity with the probability of being sick given a positive test.
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