Răspuns :
greutatea elenei=e
greutatea fratelui=f
e+f=83
f=e+8
e+e+8=83
2e+8=83
2e=75
e=75÷2=37,5kg
greutatea fratelui=f
e+f=83
f=e+8
e+e+8=83
2e+8=83
2e=75
e=75÷2=37,5kg