ioana ,gabriel si teodora au impreuna 84 de cd uri cu muzica.afla cate cd uri are fiecare copil stind ca gabriel are cu 5 cd uri mag mult decat ioana ,iar teodora are cu 8 cd uri mai mult decat gabriel..

|....Ioana...|......Gabriel....| .....Teodora...| =84

|.................|=Ioana
|,,,,,,,,,,,,,,,, |.5.|=Gabriel
|.................|.5.|..8..|=Teodora

Atunci
|....Ioana...|......Gabriel....| .....Teodora...| =

|.................||.................|.5.||.................|.5.|..8..|=84

|.................|+|.................|+5+|.................|+5+8=84

|.................|+|.................|+|.................|+5+5+8=84

|.................|+|.................|+|.................|+18=84  |o sa scadem 18 din fiecare parte

|.................|+|.................|+|.................|+18-18=84-18

|.................|+|.................|+|.................|=66
o aduinare repetata se numeste inmultire
3 * |.................|=66
 |.................|=66:3
 |.................|=22=Ioana
  |.................|.5.|=22+5=27=Gabriel
 |.................|.5.|..8..|=22+5+8=27+8=35=Teodora

 Ioana are 22 cd-uri
Gabriel are 27 cd-uri
Teodora are 35 cd-uri
 Verificare
22+27+35=49+35=84 adevarat ,problema este bine rezolvata