Practicing Success
If A and B are independent events of a random experiment such that $P(A ∩ B) =\frac{1}{6}$ and $P(\overline{A} ∩ \overline{B}) =\frac{1}{3}$, then P(A) is equal to |
$\frac{1}{4}$ $\frac{1}{3}$ $\frac{1}{6}$ $\frac{2}{3}$ |
$\frac{1}{3}$ |
We have, $⇒P(A ∩ B) =\frac{1}{6}$ and $P(\overline{A} ∩ \overline{B}) =\frac{1}{3}$ $⇒P(A)P(B)=\frac{1}{6}\, and \, P(\overline{A}) P(\overline{B}) =\frac{1}{3}$ $⇒ xy =\frac{1}{6}\, and \, (1-x)(1-y)=\frac{1}{3},$ where $ P(A)= x, P(B) = y$ $⇒xy =\frac{1}{6} $ and $ 1-x -y +\frac{1}{6}=\frac{1}{3}$ $⇒xy =\frac{1}{6}$ and $ x + y= \frac{5}{6}$ $⇒xy =\frac{1}{6} $ and $y =\frac{1}{3}$ or $ x =\frac{1}{3}$ and $ y = \frac{1}{2}$ |