de craciun,pt a face o donatie unui orfelinat,elevii claselor a 4-a au cparat 4 jocuri de constructii si 5 jocuri puzzle,in valoare de 820 lei,iar elevii claselor a 3- a au cumparat 2 jocuri de constructii si 4 jocuri puzzle in valoare de 518 lei.cat costa un joc de constructii?/dar un joc puzzle?

4 joc constr.........5 puzzle........820lei/*2

2 joc constr .........4 puzzle .......518lei/*4

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8 joc constr.........10 puzzle........1640lei

8 joc constr .........16 puzzle ......2072lei

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0 joc constr.........6 puzzle......... 432lei

1 puzzle..........432:6

1 puzzle..........72lei

2 joc constr.........4 puzzle........518lei

1 puzzle=72 lei=>4puzzle=72*4

4puzzle=288

2 joc constr=518-288

2 joc constr=230

1 joc constr=230:2

1 joc constr=115