3 mingi+4 masinute=146 lei
3 mingi+7 masinute=224 lei
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= 3 masinute=78 lei
1 masinuta=78:3
1 masinuta=26 lei
3mingi+ 4x26=146 lei
3 mingi+104=146 lei
3 mingi=146-104
3 mingi=42 lei
1 minge=42:3
1 minge=14 lei
proba:
3x14+4x26=146
42+104=146