Răspuns:
2 tone Cartofi+3 tone Ceapa=8100 lei
2 tone cartofi+7 tone ceapa=14900 lei
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4 tone ceapa=6800
tona de ceapa=1700 lei
2 tone cartofi+3x1700=8100 lei
2 tone cartofi=8100-5100
2 tone cartofi=3000
tona de cartofi=1500 lei