আপনি start off with the -1 pattern then go to the -10 3 times then আপনি go back to -1 the other two times. Like আপনি start off with 91-1=90 then -1 again to get 98 then আপনি -10 to that to get 88.Then if আপনি -10 again আপনি get 78, and after that আপনি minus ten one আরো time to get 68.