A|---V2------>------------B|---V1---->------------------------|C (locul intalnirii)
|<--------d---------------->|<--------------d1--------------->|
|<---------------------------------d2--------------------------->|
d = d2 - d1
d = V2·t - V1·t = t(V2 - V1)
t = d / (V2 - V1) = 50km / 20km/h = 2,5 h
d2 = V2·t = 75km/h ·2,4h =180 km