Discussion Forum

A streamer goes downstream from one port to another in 4 hours. It covers the same distance upstream in 5 hours. If the speed of stream is 2 km/h, the distance between the two ports is 

Answer:

Explanation:

Let the distance between the two ports be $=x$ km

Let the speed of streamer in still water  $=y$ km/h

$\frac{x}{y+2}$ $=4$

$\Rightarrow x$ $=4y+8$ -------------------(1)

$\frac{x}{y-2}$ $=5$

$\Rightarrow x$ $=5y-10$ -------------------(2)

Solving (1) & (2)

$y$ $= 18$

$x$ = 80 km