Răspuns :
231 +1/4•d=d=>231•4/4+d/4=4d/4 | •4, 231•4+d=4d, 231•4=4d-d=> 231•4=3d=> d=231•4:3=> d=77•4, d=308 km
daca a parcurs 231 km si mai are de parcurs 1/4 din drum, inseamna ca
d-d/4=231=> d(1-1/4)=231=>d(3/4)=231=>d=231*4/3=77*4=308km
d-d/4=231=> d(1-1/4)=231=>d(3/4)=231=>d=231*4/3=77*4=308km