Question

A steamer takes a time t1 to travel a distance d up a river and a time t2 to return. Find the speed of steamer in still water

Answer 1

Given:-

• streamer take t1 time to travel upstream
• t2 time to travel downstream
• distance=d

To find:-

• speed in still water

Solution:-

Let the speed in still water be X and the speed of river water is Y

Than according to question

while going upstream speed of streamer will be X-Y

And while goin downstream speed of streamer will be X+Y

$\LARGE speed= \frac{Distance}{time}$

And

$\LARGE X-Y= \frac{D}{t_1}$

$\LARGE X+Y= \frac{D}{t_2}$

Add both equations

$\large X-Y+(X+Y)= \frac{D}{t_1} +\frac{D}{t_2}$

$\LARGE 2X= \frac{D(t_1+ t_2)}{t_1\times t_2}$

$\LARGE X= \frac{D(t_1+ t_2)}{2 t_1 t_2}$