Question

Suppose you have data that shows that 12% of athletes test positive for steroids. You also know that 11% of athletes test positive for steroids and actually use steroids. What is the probability that an athlete uses steroids, given that he tests positive?

Answer 1

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Answer 2

Let A be the event that the athlete whose test for using steroids is positive, and B be the event that the athlete actually uses steroids.
P(A)=12%
P(A∩B)=11%
P(B|A)=P(A∩B)/P(A)~92%

Answer 3

Thnk You kc_kennylau