Răspuns :
Notam prima clasa cu a si a doua cu b a+b=68=>a=68-b a-5=b+5 68-b-5=b+5=>58=2b=>b=29=>a=68-29=39
a+b=68
a-5=b+5=>a=b+5+5=>a=b+10
b+10+b=68
2b=68-10
b=58:2=29 elevi intr-o clasa
a=29+10=39 elevi in a2a clasa
a-5=b+5=>a=b+5+5=>a=b+10
b+10+b=68
2b=68-10
b=58:2=29 elevi intr-o clasa
a=29+10=39 elevi in a2a clasa