Question

A streamer goes downstream from point A to B in 9hrs .from B to A ,upstream it takes 10h .if the speed is 1km/hr , what will be the speed of the streamer in still water ? also find distance between the point A to B

Answer 1

Answer:

The distance  between the point A to B 180 kilometres.

The streamer speed in still water is 19 kmph

Step-by-step explanation:

Let be the distance between the ports (in kilometres) be d

let  the streamer speed in still water be s

Then speed equation for moving downstream

$\frac{d}{9} = s + 1$------------------------(1)

The speed equation for moving upstream

$\frac{d}{10} = s - 1$-------------------------(2)

On solving (1) and (2)

$\frac{d}{9} -\frac{d}{10} = 2$

$\frac{10d -9d}{90} = 2$

$\frac{d}{90} = 2$

$d = 90 \times 2$

d =  180

Thus the distance  between the point A to B 180 kilometres.

Now from equation 1

$\frac{180}{9} = s + 1$

20 = s + 1

20 -1 = s

19 = s

The streamer speed in still water is 19 kmph