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 July 25, 2026 by Teachoo

Question 8 - For any two events A and B, if P(A')=1/2, P(B')=2/3, P(A - CBSE Class 12 Sample Paper for 2025 Boards

-lock-

part 2 - Question 8 - CBSE Class 12 Sample Paper for 2025 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards - Class 12

part 3 - Question 8 - CBSE Class 12 Sample Paper for 2025 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards - Class 12

part 4 - Question 8 - CBSE Class 12 Sample Paper for 2025 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards - Class 12

-endlock-

Next: Question 9 Important → Remove Ads

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 is an IIT Kanpur graduate and has been teaching for 16+ years. At Teachoo, he breaks down Maths, Science and Computer Science into simple steps so students understand concepts deeply and score with confidence.

Many students prefer Teachoo Black for a smooth, ad-free learning experience.

Class 6

Class 7

Class 8

Class 9

Class 10

Class 11

Class 12

Courses

Interesting

Popular