Question

The sum of probabilities of all possible events is always

Answer 1

The sum of probabilities of all possible events associated with a sample space is always $1$.

If $E_1,E_2,E_3,.......E_n$ are the events associated with a sample space, then

$P\left(E_1\right)+P\left(E_2\right)+P\left(E_3\right)+.........+P\left(E_n\right)=1$