Question 17
Five teams played in a competition and every team played each of the four other teams once. Each team received three points for a match it won, one point for a match it drew and no points for a match it lost. At the end of the competition the points were: Yellows 10, Reds 9, Greens 4, Blues 3 and Oranges 1. How many matches did the Greens win against the other four teams?