7). (3 points) Seven friends went to an amusement park. Each wanted to ride the roller coaster with each of the others. If only 2 can ride the roller coaster together at one time, how many rides are needed so each can ride with all others once?


Number of rides:______

8). (3 points) 8 people go to a party. They all shake hands with each other. How many handshakes are there?


Number of handshakes:______

9). (3 points) How many 2-person teams can you make out of a basketball club that has 7 players?


Number of teams:______

10). (3 points) Skittles candy has 6 different colors. How many different color combinations can I pick if I select 2 candies and each of the 2 is a different color?


Number of 2-candy combinations:______