1. Xiao Li recently participated in a swimming competition. Before the game, she shook hands with all the athletes to show her friendship. Xiaoli remembers shaking hands 50 times, so there are (50+ 1=5 1) athletes in this competition. (counting Xiaoli)

2. The sum of five consecutive numbers is the smallest three digits, in which the largest number is (22) and the smallest number is (18).

3. Find a number filling mode: from small to large, once every three times, the order is 1, 4, 7, 10... 100, and the number is (298).

5. Xiao Hao participated in the team aerobics performance, and ranked in the middle of a phalanx team, ranking ninth around. There are (289) people participating in the group gymnastics performance. (counting Xiao Hao)