SSC CHSL 2023 PYQ — Question 12

SSC CHSL Tier II - 02 Nov 2023 - Shift 1 • Quantitative Aptitude • Q12

If A and B events with P(A) = 38\frac{3}{8}, P(B) = 12\frac{1}{2} and P(A ∩ B) = 14\frac{1}{4}. Find P(A̅ ∩ B̅).

Show answer & explanation

Correct answer: B

Explanation

The correct answer is option 2 i.e. 3/8.

Given that

 P(A) = 38\frac{3}{8}, P(B) = 12\frac{1}{2} and P(A ∩ B) = 14\frac{1}{4}.

P(A U B) = P(A) + P(B) - P(A ∩ B)

P(A̅ ∩ B̅) = 1 - P(A U B)

⇒ P(A U B) = 38\frac{3}{8} + 12\frac{1}{2} -  14\frac{1}{4} = 5/8

Hence,

P(A̅ ∩ B̅) = 1 - 5/8 = 3/8