The road ministry has assigned 80 informal companies to repair 2400 roads. These roads connect 100 cities to each other. Each road is between 2 cities and there is at most 1 road between every 2 cities. We know that each company repairs 30 roads that it has agencies in each 2 ends of them. Prove that there exists a city in which 8 companies have agencies. ceiling functioncombinatorics proposedcombinatorics