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Airforce Group X 12 Jul 2021 Shift 1 Memory Based Paper

Option 1 : 0.2

__Concept:__

P(A ∪ B) = P(A) + P(B) - P(A ∩ B)

For mutually exclusive events A and B, P(A ∩ B) = 0

__Calculation:__

We know, for mutually exclusive events A and B, P(A ∩ B) = 0

∴ P(A ∪ B) = P(A) + P(B) - 0

= P(A) + P(B)

⇒ 0.6 = 0.4 + P(B)

∴ P(B) = 0.2

Hence, the correct option is 1.