Show the formula used to answer each of the following Event

Show the formula used to answer each of the following. Event A and Event B are Mutually Exclusive. If P(A) = 0.3 and P(B) = 0.4. what is P(A or B)? Event A and Event B are NOT Mutually Exclusive. If P(A) = 0.3. P(B) = 0.4, P(A and B) = 0.1, what is P(A or B)? Event A and Event B are Independent events. IF P(A) = 0.3, P(B) = 0.4, what is P(A and B)? Event A and Event B are NOT Independent events. IF P(A) = 0.3, P(B) = 0.4, P(B/A) = 0.2 what is P(A and B)?

Solution

22) P(A or B)=P(A)+P(B)=0.3+0.4=0.7

23) P(A or B)=PA)+P(B)-P(A and B)=0.3+0.1-0.1=0.3

24) P(A and B)=P(A)*P(B)=0.3*0.4=0.12

25) P(A and B)=P(B/A)*P(A)=0.2*0.4=0.08