Răspuns :
a+b+c=a+50+c+c=> a+50+2c=340
a+2c=340-50
a+2c=290
=> 80+2c =290 => 2c= 290-80=210
=> c=210:2 =105
=> b = 50+105 = 155
verificare : 105+155+80 =340
a+2c=340-50
a+2c=290
=> 80+2c =290 => 2c= 290-80=210
=> c=210:2 =105
=> b = 50+105 = 155
verificare : 105+155+80 =340