Question

is probability of occurrence of at least one of event A B=probability of occurrence of A or B=p(A+B)

Answer 1

Dear student,
YES the probability of occurence of A or B and probability of occurence of atleast one of A or B is same.
it is generally denoted by $P(A\cup B)orP(A+B)$
and $P(A\cup B)=P\left(A\right)+P\left(B\right)-P(A\cap B)$
if A and B are mutually exclusive events then $P(A\cap B)=0$
in that case $P(A\cup B)=P\left(A\right)+P\left(B\right)$

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