Răspunsuri

2014-05-04T18:05:08+03:00
Notam cu x traseul
3x/5+20x/100+56=x⇔3x/5+x/5+56=x⇒4x/5+56=x⇒56=x-4x/5⇒286=5x-4x⇒x=286 km(traseul)