 Hello and welcome to the session. Let us discuss the following question. It says given probability of A is 3 by 5 probability of B is 1 by 5 Find probability of A or B if A and B are mutually exclusive events To solve this problem. We need to know a fact it says that if A and B are mutually exclusive events then probability of A in the section B is 0 and We also need to know that in that case probability of A union B is equal to probability of A plus probability of B. So this knowledge will work as the idea. Let us now move on to the solution We are given that probability of A is 3 by 5 and probability of B is 1 by 5 Now we have to find probability of A or B. A or B means even A or B or both That is it is same as probability of A union B Right and we know that the probability of A union B is probability of A plus probability of B if A and B are mutually exclusive Now probability of A is 3 by 5 and probability of B is 1 by 5 So probability of A or B is 4 by 5. That's all for the session. Goodbye and take care