Question

A boat travels 8 km. in 1 hr downstream and
4 km. in 1 hrs. upstream. Find how much time
this boat will take to travel 18 km. in still water?​

Answer 1

Answer:

v1 + v2 = 8/1 = 8 ...(i)

v1 - v2 = 4/1 = 4...(ii)

Adding equations (i) and (ii), we get

v1 = 4km/hr

t=d/v1=18/4 =9/2 hrs.= 4 and a half hours