Co 3 thanh pho A ,B,C thanh pho B nam giua Ava C quang duong AB =120km quang duong BC =150km luc 6 gio 30 phut co o to di tu B den C voi van toc 34km/gio cung luc o to tu B den A voi van toc 25km/gio hoi den may gio thi khoang cach o to va C bang khoang cach o to va A