An examination consists of two papers, Paper 1 and Paper 2. The probability of failing in Paper 1 is 0.3 and that in Paper 2 is 0.2. Given that a student has failed in Paper 2, the probability of failing in Paper 1 is 0.6. The probability of a student failing in both the papers is
C
Correct answer
Explanation
$\text{Probability of failing in paper 1 is} \hspace{1cm} P(A) = 0.3
\\
\text{Possibility of failing in paper 2 is} \hspace{1cm} P(B) = 0.2
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Probability of failing in paper 1, when
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\text{Student has failed in paper 2 is} \hspace{1cm} P(\frac{A}{B}) = 0.6
\\
\text{We know that}
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P(\frac{A}{B}) = \frac{(P \cap B)}{P(B)}
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or \hspace{1cm} P(A \cap B) = P(B) P (\frac{A}{B}) = 0.6 \times 0.2 = 0.12$