问题
问答题
In the diagram above, points A, B, C, D, and E represent the five teams in a certain league in which each team must play each of the other teams exactly once. The segments connecting pairs of points indicate that the two corresponding teams have already played their game. The arrows on the segments point to the teams that lost; the lack of an arrow on a segment indicates that the game ended in a tie. After all games have been played, which of the following could NOT be the percent of games played that ended in a tie ？
答案
参考答案：
10%不可能是平局所占的百分比。
解析：
根据题意可知5支球队共进行[*]场比赛即10场比赛。由图形可知，目前已进行了7场比赛，其中有2场比赛是平局，则平局已经占了总比赛数目至少20%的比例，所以10%不可能是平局所占的百分比。