Răspuns :
Nr de bani al Alexandrei = x
Al Andreei = y
al lui adi =z
x+y+z=1600 lei
y=z+200 lei
x=y+z
Deci inlocuim in ecuatie
z+200 +z +z+200+z=1600
4z+400=1600
4z=1200
z=300
y=z+200=>y=300+200=>y=500
x=300+500=>x=800
x+y+z=1600=>800+500+300=1600=>1600=1600
Al Andreei = y
al lui adi =z
x+y+z=1600 lei
y=z+200 lei
x=y+z
Deci inlocuim in ecuatie
z+200 +z +z+200+z=1600
4z+400=1600
4z=1200
z=300
y=z+200=>y=300+200=>y=500
x=300+500=>x=800
x+y+z=1600=>800+500+300=1600=>1600=1600
Al + An + Ad=1600
An=Ad+200
Al=An+Ad
Inlocuim in prima relatie
Ad+200 +Ad +Ad+200+Ad=1600 =>4Ad+400=1600 =>4Ad=1200 =>Ad=1200/4 =>Ad=300
An=Ad+200 =>An=300+200=500
Al=An+Ad =>Al=500+300=800
An=Ad+200
Al=An+Ad
Inlocuim in prima relatie
Ad+200 +Ad +Ad+200+Ad=1600 =>4Ad+400=1600 =>4Ad=1200 =>Ad=1200/4 =>Ad=300
An=Ad+200 =>An=300+200=500
Al=An+Ad =>Al=500+300=800