You are in:/ / (Math Quiz 10 – CT) Dung has 8 friends. Dung wants to invite 4 out of 8 friends to his hometown for the weekend. But in those 8 friends, there are 2 friends, Hung and Tuan, who don’t like going out together. So the number of ways to choose a group of 4 people to return to Dung’s hometown is?