Question

The probability that at least one of the events A and B occurs is 0.6. If A and B occurs simultaneously with probability 0.2, then $P\left(\overline{A}\right)+P\left(\overline{B}\right)$ is equal to

• A. 0.4
• B. 0.8
• C. 1.2
• D. 1.4

Answer 1

The correct option is C 1.2

Given, $P(A\cup B)=0.6,P(A\cap B)=0.2$
$\therefore P\left(\overline{A}\right)+P\left(\overline{B}\right)=[1-P(A\left)\right]+[1-P(B\left)\right]=2-\left[P\right(A)+P(B\left)\right]=2-\left[P\right(A\cup B)+P(A\cap B\left)\right]=2-[0.6+0.2]=1.2$