Question

If the probability of $x$ to fail in the examination is $0.3$ and that for $Y$ is $0.2$, then the probability that either $X$ or $Y$ fail in the examination is

• A. $0.5$
• B. $0.44$
• C. $0.6$
• D. None of these

Answer 1

The correct option is B $0.44$

Given, $P\left(x\right)=0.3,P\left(y\right)=0.2$
Now, $P(x\cup y)=P\left(x\right)+P\left(y\right)-P(x\cap y)$
Since, these are independent events, so
$P(x\cap y)=P\left(x\right).P\left(y\right)$
Thus, the required probability is $0.3+0.2-0.06$ $=0.44$.