
no. of stemps to Xian = 60
no. of stamps to Kai = 76
After joining the club:-
1st month
Xian = 60+12=72
Kai = 76+8 = 84
2nd month
Xian = 72 +12 = 84
Kai = 84 +8 = 92
3rd month
Xian = 84 + 12 = 96
Kai = 92 + 8 = 100
4th month
Xian = 96 +12 = 108
Kai = 100 + 8 = 108
So after four month they will have the equal stamps which were 108.
HOPE IT HELPS YOU.