1. ## help-probability

Don't know how to do these questions. Understand how to use Venn diagrams but to many terms for my mind. Can anybody tell me how to figure this out?

2. Originally Posted by Arbitur
Don't know how to do these questions. Understand how to use Venn diagrams but to many terms for my mind. Can anybody tell me how to figure this out?
Since $\displaystyle P(A \mbox{ and }B)=P(A)P(B)$ where $\displaystyle A,B$ are disjoint.
Thus, the answer to the first question is $\displaystyle (.2)(.3)=.06$.

Since $\displaystyle P(A\mbox{ or }B)=P(A)+P(B)$ where $\displaystyle A,B$ are disjoint.
Thus, the answer to the second question is $\displaystyle (.2)+(.3)=(.5)$.

Since $\displaystyle P(A)+P(B)+P(C)=1$ where $\displaystyle A,B,C$ are disjoint.
Thus, the answer to the third question is $\displaystyle 1-.5=.5$.
Q.E.D.