Question 8 - CBSE Class 12 Sample Paper for 2025 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards

Last updated at Dec. 13, 2024 by Teachoo

-lock-

-endlock-

Next: Question 9 Important → You saved atleast 2 minutes of distracting ads by going ad-free. Thank you :)

You saved atleast 2 minutes by viewing the ad-free version of this page. Thank you for being a part of Teachoo Black.

Transcript

Question 8 For any two events 𝐴 and 𝐵, if 𝑃(𝐴 ‾)=1/2,𝑃(𝐵 ‾)=2/3 and 𝑃(𝐴∩𝐵)=1/4, then 𝑃(𝐴 ‾/𝐵 ‾) equals: (A) 3/8 (B) 8/9 (C) 5/8 (D) 1/4Now, 𝑃(𝐴 ‾/𝐵 ‾ )=(𝑃(𝐴 ̅ ∩ 𝐵 ̅))/(𝑃(𝐵 ̅)) Using 𝑷(𝑨 ̅ ∩ 𝑩 ̅ )=𝑃((𝐴∪𝐵) ̅ ) =𝟏−𝑷(𝑨∪𝑩) Thus, 𝑷(𝑨 ‾/𝑩 ‾ )=(𝟏 − 𝑷(𝑨 ∪ 𝑩))/(𝑷(𝑩 ̅)) Finding 𝑷(𝑨∪𝑩) Given 𝑃(𝐴 ‾)=1/2,𝑃(𝐵 ‾)=2/3 and 𝑃(𝐴∩𝐵)=1/4 Now, 𝐏(𝐀)=1−𝑃(𝐴 ‾ ) =1−1/2 =𝟏/𝟐 Also, 𝐏(𝐁)=1−𝑃(𝐵 ‾ ) =1−2/3 =𝟏/𝟑 So, the correct answer is (C) Now, 𝑷(𝑨∪𝑩)=𝑃(𝐴)+𝑃(𝐵)−𝑃(𝐴∩𝐵) Putting values =1/2+1/3−1/4 =(6 + 4 − 3)/12 =𝟕/𝟏𝟐 Now, 𝑷(𝑨 ‾/𝑩 ‾ )=(1 − 𝑃(𝐴 ∪ 𝐵))/(𝑃(𝐵 ̅)) =(1 − 7/12)/(2/3) =(5/12)/(2/3) =5/12 ×3/2 =𝟓/𝟖 So, the correct answer is (C)

Made by

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science and Computer Science at Teachoo

Class 6

Class 7

Class 8

Class 9

Class 10

Class 11

Class 12

Courses

Interesting

Popular