The probability that a company executive will travel by plane is (2/5) and that he will travel by train is (1/3). Find the probability of his travelling by plane or train.
let A denote the event that a company executive will travel by plane and B denote the event of him travelling by train
Given : P(A) = 
, P(B) = 
To find : Probability of a company executive will be travelling by plane or train=P(A or B)
Formula used : P(A or B) = P(A) + P(B) - P(A and B)
Probability of a company executive will be travelling in both plane and train =P(A and B)= 0
(as he cannot be travelling by plane and train at the same time)
P(A or B) = 
+ 
– 0
P(A or B) = 
P(A or B)= 
Probability of a company executive will be travelling by plane or train= P(A or B) = 
1