In one game, probability that a gamer scores win is 1/4. If X is number of tries( games ) that gamer has done in order to achieve score:
(NOTE!: every try is independent from the other)
a) Define the probability that gamer scored a win in 3 tries.
b) Define the probability that gamer will have at least three failures before he scores 2 wins.
I have tried to do it this way, but I am not sure if it is OK. a) P(win in 3 tries) = 1/4*1/4*1/4 = 1/64. b) for this task I have no idea from where to start.( I need great help here )