1) 777 = 7*111 = 7*3*37 = 21*37
2) 121*19 + 212*19 = (121+212)*19 = 333*19 = 111*3*19 = 57*111
3) 765*25 - 421*25 = (765-421)*25 = 344*25 = 86*4*25 = 100*86
1) 777 = 7*111 = 7*3*37 = 21*37
2) 121*19 + 212*19 = (121+212)*19 = 333*19 = 111*3*19 = 57*111
3) 765*25 - 421*25 = (765-421)*25 = 344*25 = 86*4*25 = 100*86