Answer:
9
Explanation:
If 24 points is half the number of points all other players scored, then the points scored by all other players total 24·2 = 48.
All points together total ...
24 + 48 = 72
A point is awarded for each game, so there were a total of 72 games.
N players will play a total of (N/2)(N-1) games if they play each opponent once. Here, each opponent is played twice, so the total number of games played by N players is ...
N(N-1) = 72
9·8 = 72 ⇒ N = 9
The number of players in the championship was 9.