Tic Tac Toe

Here are all the possibilities to continue the game :-

$1=X$ wins , $-1=O$ wins , $0 =$ draw .

The answer is $\frac{2}{6}$

There is only one way $X$ can win: diagonally from top left to bottom right (note that $X$ cannot win in the leftmost column, as that would necessitate $O$ playing in the bottom right square and winning before $X$ does). Thus, out of three possible first moves, two leave $X$ with the chance to win. Out of the remaining two spaces for $O$ to play, one allows $X$ to win. Thus the probability of $X$ winning is $\frac{2}{3}\times\frac{1}{2} = \frac{1}{3} \approx \boxed{0.333}$ .