yes 答案是 n=3 (唯一解）。

as to why we focus on the games won by men, it's because by eyeballing the question there are twice as much men as women in the game, but men only won 5/12 of the game so you would focus on the limitation of n that would make this feasible since men would win at least games among themselves. by solving that, n can only be 1, 2, or 3, then you can use elimination to find out the correct answer which is 3. if it turns out by solving the equation that n has many possible answers, then you would have to think of other ways to find the final answer, but I guess for 8th grade the question is not that complicated. hope this helps.