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If P(A given B) = 0.4 and P(B) = 0.5, P(A and B) is
A0.10
B0.20
C0.90
D0.45
Answer & Solution
Correct answer: B. 0.20
1. By conditional definition: P(A | B) = P(A and B) / P(B).
2. P(A and B) = P(A | B) * P(B).
3. = 0.4 * 0.5.
4. = 0.20.
_Source: ICAI BoS Foundation Paper 3, Ch 15 'Probability', p.10_
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