Consider an unending sequence of independent trials, where each trial is equally likely to result in any of the outcomes 1, 2, or 3. Given that outcome 3 is the last of the three outcomes to occur, find the conditional probability that
(a) the first trial results in outcome 1;
(b) the first two trials both result in outcome 1.
Step 1 of 3:
It is given that each trial is equally likely to result any one of the outcomes 1,2,3 in a unending sequence of independent trials.
Also, it is given that 3 is last outcome to occur.
Using this we need to find the required conditional probabilities.