WAEC - Further Mathematics (2007 - No. 32)
X and Y are two independent event. If \(P(X) = \frac{1}{5}\) and \(P(X \cap Y) = \frac{2}{15}\), find \(P(Y)\).
\(\frac{2}{3}\)
\(\frac{2}{5}\)
\(\frac{1}{3}\)
\(\frac{1}{5}\)
คำอธิบาย
For independent events \(P(X \cap Y) = P(X) \times P(Y)\)
\(\frac{2}{15} = \frac{1}{5} \times P(Y)\)
\(P(Y) = \frac{2}{15} ÷ \frac{1}{5} = \frac{2}{3}\)