Question

A boat takes 19 hours for travelling downstream from point a to point b and coming back to a point c midway between a and b. If the velocity of the stream is 4 km/h and the speed of the boat in still water is 14 km/h, what is the distance between a and b?

Answer 1

Let distance d between a and b
Than t1 = d /(14-4)=d/10
t2 = d/2*(14+4)=d/36
t1+t2 = 19=d/10+d/36
d = 19*360/(36+10)=19*360/46