A river flows at 1.5 kmph and a boatman who can row at 2.5 kmph on still water, takes 7hours to go a certain distance up the stream and return again to the starting point. Find the total distance covered by the boatman.

Question

cwrw238 · Answer

Hint :  going up the stream his speed will be 2.5 - 1.5  = 1 kmph as he is rowing against the flow

coming back his speed will be 2.5 + 1.5 = 4 kmph

cwrw238 · Answer

suppose he travels x km  up the stream 
so  

speeed = distance / time

1 = x / t1   where  t1 = time taken 
coming back

4 = x / t2    where t2 = time taken to come back


so we have x = t1   and x = 4t2

so t1 = 4t2

and he travels for total time of 7 hours

can you continue from here?

you need to find the values of x

cwrw238 · Answer

* value of x