I think question has faulty values.
Okay, study this :
If you don't understand, then tell me.
Ahaha Fidato, Very good point
but you would be correct if you are sure that tht probability is independant... but its not!!
This means that the prob of winning the first time is DIFFERENT than the probabiity of winning the second game!!!!
Got it?
P.S: if you aren't convinced try finding the prob of winning exaclty one game it will come up as 0.5 not 0.3...
Life is simple, no need to go all through this