A Wicked Math puzzle

3 + 3 + 3 + 2 = 11

2 + 8 + 2 + 1 = 13

1 + 8 + 1 + 1 = 11

2 + 2 + 2 + 3 = 9


8 ; 21 ; 8 ; 7

understand? or cycle stand? :slight_smile: