Scoring (Wikipedia) 

Scores are determined by summing the top four or five individual finishing places on each team. In international competition, a team typically consists of six runners, with the top four scoring. In the United States, the most common scoring system is seven runners, with the top five scoring. Points are awarded to the individual runners of eligible teams, equal to the position in which they cross the finish line (first place gets 1 point, second place gets 2 points, etc.). The points for these runners are summed, and the lowest score wins. Individual athletes, and athletes from incomplete teams (teams consisting of less than 5 athletes or teams) and individuals who have been disqualified are excluded from scoring. Ties are usually broken by the position of each team’s sixth runner.

The lowest possible score in a five-to-score match is 15 (1+2+3+4+5), achieved by a team’s runners finishing in each of the top five positions. If there is a single opposing team then they would have a score of 40 (6+7+8+9+10), which can be considered a “sweep” for the winning team. In some competitions a team’s sixth and seventh runner are scored in the overall field and are known as “pushers” or “displacers” as their place can count ahead of other runners, giving other teams more points. In the above match, if there are two non-scoring runners and they came 6th and 7th overall, the opponent’s score would be 50 (8+9+10+11+12). Accordingly, the official score of a forfeited dual meet is 15–50.