Two groups A and B are playing a game.
The first group that wins 3 times is the winner.
The probability that group A will win at on game is $\frac12$ and the same thing for group B.
$X$ = The number of games until one of the groups (A or B) will be the winner.
What is the probability function of $X$? (as table).
[We know that there is only three options].
Please help me with the table of this probability function...
Thank you so much!
Here is my try after your help: