Răspuns:
notam a= gaini b= rate c= gaste d= curci
a+b+c+d= 128
a+c=86 => c= 86- a
a+b=77 => b= 77-a
a+d=83 => d= 83-a
a+86-a +77-a +83-a= 128
163+83-2xa= 128
246- 2xa=128 246- 128= 2xa
2xa=118 a= 118 : 2= 59 gaini
c=86-59= 27 gaste
b= 77-59= 18 rate
d= 83-59= 24 curci
verificare: 59+ 18 +27+24= 77+51= 128 pasari