BITSAT 2018 Slot 2 Solved Paper

In a test an examiner either guesses or copies or knows the answer to a multiple choice question with 4 choices. The probability that he/she makes a guess is

1

3

. The probability that he/she copies the answer is

1

6

. If the probability that the answer is correct, given that he/she copied, it is

1

8

, then the probability that he/she knows the answer to a question given that he/she correctly answered it, is