Answer:
0.82
Step-by-step explanation:
given that an athlete suspected of having used steroids is given two tests that operate independently of each other.
Test A has probability 0.9 of being positive if steroids have been used. Test B has probability 0.8 of being positive if steroids have been used.
A and B are independent of each other
Hence P(AB) = P(A) P(B)
Required probability = the probability that atleast one test is positive if steroids have been used
= P(AUB)
= P(A)+P(B)-P(AB)
= 0.9+0.8-0.9*0.8
= 0.82