Probability that both compounds are A = P(1st is A)P(2nd is A) = (1/2)(9/19) = 0.24
Probability that both are B = 0.24
Probability that both are same = 0.47
Probability that they are different = 0.53
Conclusion: Always predict they are different.
Probability that both compounds are A = P(1st is A)P(2nd is A) = (1/2)(9/19) = 0.24
Probability that both are B = 0.24
Probability that both are same = 0.47
Probability that they are different = 0.53
Conclusion: Always predict they are different.