In our day-to-day life, we perform many activities which have a fixed result no matter any number of times they are repeated. Such as, given any triangle, without knowing the three angles, we can definitely say that the sum of measure of angles is 180∘.
We also perform many experimental activities, where the result may not be same, when they are repeated under identical conditions. Such as when a coin is tossed it may turn up a head or a tail, but we are not sure which one of these results will actually be obtained. Such experiments are called random experiments.
An experiment is called random experiment, if it satisfies the following two conditions
(i) It has more than one possible outcome.
(ii) It is not possible to predict the outcome in advance.