Question

A streamer goes downstream from one port to another in 15 hours. It covers the same distance

upstream in 20 hours. If the speed of the stream be 3 km/hr, find the speed of the streamer in still water

and the distance covered.

Answer 1

Here is ur answer,

Let the speed of streamer be x km/h.

• In the case of downstream

         Speed = (x +3) km/h

•   Time = 15 hrs

So

• Distance = Time x speed

                       = 15 (x+3) km

• In the case of upstream

       speed = ( x-3) km/h

• Time = 20 hrs

So

distance = 20 ( x-3) km

Since distance is same.

So,

15(x+3) = 20(x-3)

⇒ 15 x +45 = 20 x  - 60

⇒ 45 + 60 = 20 x - 15 x

⇒ 5 x = 105

so,

x = 21

The speed of streamer = 21 km/h.

And distance =

15 (x+3) = 15 ( 21+3) = 15 x 24 = 360 km

                                                 OR

Distance = 20 ( x -3 ) = 20 ( 21-3 ) = 20 x 18 = 360 km

Hope it helps u.

Thank u.

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