"elevii clasei a patra au rezolvat probleme timp de o saptamana.In prima zi au rezolvat 3/6 din ele, a doua zi 6/12 din rest , atreia zi 1/3 din noul rest, iar a patra zi ultimele 8 probleme.Cate probleme au rezolvat in fiecare zi?"
prima zi⇒3/6·y=1/2·y=y/2; ⇒a ramas=y-y/2=2y/2-y/2=y/2; ⇒a doua zi⇒6/12·y/2⇒3/12·y⇒1/4·y=y/4; ⇒a ramas y/2-y/4=2y/4-y/4=y/4; ⇒a treia zi⇒1/3·y/4⇒y/12; ⇒a ramas y/4-y/12 ⇒3y/12-y/12⇒2y/12 ⇒2y/12=8 ⇒y=12·8/2 ⇒y=12·4 ⇒y=48[probleme au rezolvat in fiecare zi];
