[讨论][求助]

各位大侠，帮个忙吧～快考了～有数学题不懂：

For a certain race, 3teams were allowed to enter 3 members each. A team earned 6-n points whenever one of its members finished in nth place,where 1<=n<=5. There were no ties,disqualifications or withdraws. If no team earned more than 6 points, what is the least possible score a team could have earned? 答案是３　怎么算的呀？