JEE Main 2025 Mathematics question
Two balls are selected at random one by one without replacement from a bag containing 4 white and 6 black balls. If the probability that the first selected ball is black, given that the second selected ball is also black, is , where gcd (m,n) = 1, then m + n is equal to :
Answer: (1)
Solution
Using Bayes' theorem, P = 5/9. m=5, n=9, m+n=14.