Răspuns :
a+b+c=203
b=3c
a=b-7=3c-7
3c-7+3c+c=203
7c=203+7
7c=210
c=210:7=30
b=3c=3x30=90
a=b-7=90-7=83
83+90+30=203(verificare)
b=3c
a=b-7=3c-7
3c-7+3c+c=203
7c=203+7
7c=210
c=210:7=30
b=3c=3x30=90
a=b-7=90-7=83
83+90+30=203(verificare)
Notez cu x, y, z-numerele.
x+y+z=203
y=x+7=>x=y-7=3z-7
y=3z
3z-7+3z+z=203
7z-7=203
z=203+7/7
z=210/7
z=30=>y=90; x=83
x+y+z=203
y=x+7=>x=y-7=3z-7
y=3z
3z-7+3z+z=203
7z-7=203
z=203+7/7
z=210/7
z=30=>y=90; x=83