CBSE Class 12 Sample Paper for 2026 Boards
CBSE Class 12 Sample Paper for 2026 Boards
Last updated at November 26, 2025 by Teachoo
Transcript
Question 38 (ii) A student is selected at random, and he is found to suffer from anxiety and low retention issues. What is the probability that he/she spends screen time more than 4 hours per day?We need to find P(E1|A) Using conditional probability formula P(E1|A) = (š·(š¬_šā© šØ))/(š·(šØ)) Now, we found P(A) in last part For š·(š¬_šā© šØ) can also write P(A|E1) = (š(š“ ā© šø_1))/(š(šø_1)) Putting values 80/100=(š(š“ ā© šø_1))/(60/100) 80/100 Ć60/100=š(š“ ā© šø_1) š·(šØ ā© š¬_š )=šš/ššš Ćšš/ššš š(š“ ā© šø_1 )=8/10 Ć6/10 š·(šØ ā© š¬_š )=šš/ššš Putting values in (1) P(E1|A) = (š(šø_1ā© š“))/(š(š“)) P(E1|A) = (48/100)/(72/100) P(E1|A) = šš/šš P(E1|A) = 6/9 P(E1|A) = š/š Thus, required probability is š/š