Răspuns:
1kg port+3kg pere=14 ron /x3
3 kg port.+5kg pere=30 ron
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3 kg port+9 kg pere=42 ron
3 kg port+5kg pere=30 ron
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4 kg pere=12 ron
pere=3 ron kilogramul
1 kg port+9 kg pere=14 ron
1 kg portocale=14-9=5 ron
Explicație pas cu pas: