WAEC - Further Mathematics (2008 - No. 23)
If events A and B are independent and \(P(A) = \frac{7}{12}\) and \(P(A \cap B) = \frac{1}{4}\), find P(B).
\(\frac{3}{7}\)
\(\frac{4}{7}\)
\(\frac{5}{7}\)
\(\frac{6}{7}\)
설명
\(P(A) = \frac{7}{12}\)
\(P(A \cap B) = \frac{1}{4} = P(A) \times P(B)\) (Independent events)
\(\frac{1}{4} ÷ \frac{7}{12} = \frac{1}{4} \times \frac{12}{7} \)
= \(\frac{3}{7}\)