Question

A steamer goes downstream and covers the distance between two ports in 4 hours while it
covers the same distance upstream in 5 hours. If the speed of stream is 2 km/h, find the
speed of steamer in still water.​

Answer 1

SOLUTION :-

Let the speed of the streamer be x .

Given that,

Speed of stream = x

Speed of streamer in upstream = ( x + 2 )

Speed of streamer in downstream = ( x - 2 )

Distance covered by the streamer in 4 hours downstream,

                                                            = 4 ( x + 2 )

                                                            = 4x + 8

Distance covered by the streamer in 5 hours upstream,

                                                             = 5 ( x - 2 )

                                                             = 5x - 10

According to the question,

Distance covered by the streamer in 4 hours downstream and 5 hours

upstream are equal.

$\longrightarrow\sf 4x+8=5x-10 \\\\\longrightarrow 4x-5x= -10-8 \\\\\longrightarrow -x = -18\\\\\longrightarrow\bf x = 18$

Speed of the streamer in still water = 18 km/h

Answer 2

Given :

• A steamer goes downstream and covers the distance between two ports in 4 hours while it covers the same distance upstream in 5 hours. If the speed of stream is 2 km/h .

To find :

• The speed of steamer in still water .

Solution :

Let the speed of the steamer in still water be x km/hr.

We have, speed of the stream 2 km/hr.

Speed downstream = (x + 2) km/hr.

Speed upstream = (x - 2) km/hr.

Distance covered in 4 hours while going downstream = 4 (x + 2) km. and distance covered in

5 hours while going upstream = 5 ( x -2 ) km.

According to the given condition,

4 (x + 2) = 5(x - 2)

4x + 8 = 5x - 10

4x 5x = -10 -8

-x = -18

x = 18

Hence, the speed of the steamer in still water is 18 km/hr .