Answer:
Probability = 10% = 1/10
Step-by-step explanation:
Prob (Medical company determines steroids use) = P(D) = 95%
Prob (Group athletes use steroids) = P(S) = 10%
Prob (athlete use steroids & medical determines steroid use) = P (D ∩ S) = 95% x 10% = 9.5%
Conditional Prob [ P (S) I P (D) ] = P (S ∩ D) / P (D)
= 9.5% / 95% = 10% , ie = 1/10