Anubhab faces a multiple-choice question (MCQ) with four alternative choices, where only one is the right choice. There is no negative mark for making a wrong choice. Assume that the probability that he knows the answer is 0.50. The probability of making the correct choice is 0.25, if he does not know the answer. He got full marks in this question. The probability that he knew the answer is ________ (rounded off to one decimal place).
IIT JAM 2025 Question 54: Probability and Bayes' theorem
Answer and worked solution
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Probability and Bayes' theorem has come up 190 times in 7 exams since 2004.
What this question tests
This question is on Total probability and Bayes' theorem, part of Probability and Bayes' theorem in Statistics.
Reversing a conditional probability and updating beliefs from evidence.
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