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I would say that the prob for both events to occur is 0,8*0,6=0,48.
The problem is if both events may occur at the same time , in other words if they are not mutually exclusive

I would say that the prob for both events to occur is 0,8*0,6=0,48. The problem is if both events may occur at the same time , in other words if they are not mutually exclusive

But the problem here is that it does not state if they are mutually exclusive events or not... If so then only prob for both is 0....

Combining the two still does not give us P(A and B). Hence E

Since there are only 2 events, P(A or B) = 1 Thus, from (1) + (2), we can obtain P(A and B). Hence the answer should be (C), right ?

According to your explanation, since P(A or B)=1, P(A and B) = 0.4. What if A and B are mutually exclusive (which we dont know) ? Then P(A and B) would have to be 0. So you see, you have two answers: 0.4 and 0. Not possible, is it?